Recently we got a new contributor on RSS Bandit who uses the ReSharper refactoring tool. This has led to a number of changes to our code base due to suggestions from ReSharper. For the most part, I've considered these changes to be benign until recently. A few weeks ago, I grabbed a recent snap shot of the code from SVN and was surprised to see all the type declarations in method bodies replaced by implicitly typed variable declarations (aka the var keyword). Below is an excerpt of what some of the "refactored" code now look likes.

            var selectedIsChild = NodeIsChildOf(TreeSelectedFeedsNode,
selectedNode); var isSmartOrAggregated = (selectedNode.Type == FeedNodeType.Finder || selectedNode.Type == FeedNodeType.SmartFolder); //mark
all viewed stories as read if (listFeedItems.Items.Count > 0){
listFeedItems.BeginUpdate(); for (var i = 0;
i < listFeedItems.Items.Count;
i++){ var lvi = listFeedItems.Items[i]; var newsItem = (INewsItem)
lvi.Key;

I found this change to be somewhat puzzling since while it may have shortened the code by a couple of characters on each line but at the cost of making the code less readable. For example, I can't tell what the type of the variable named lvi is just by looking at the code.

I did some searching online to see how the ReSharper team justified this refactoring "suggestion" and came across the blog post entitled  ReSharper vs C# 3.0 - Implicitly Typed Locals by a member of the ReSharper team which contains the following excerpt

Some cases where it seems just fine to suggest var are:

1. New object creation expression: var dictionary = new Dictionary<int, string>();
2. Cast expression: var element = (IElement)obj;
3. Safe Cast expression: var element = obj as IElement;
4. Generic method call with explicit type arguments, when return type is generic: var manager = serviceProvider.GetService<IManager>()
5. Generic static method call or property with explicit type arguments, when return type is generic: var manager = Singleton<Manager>.Instance;

However, various code styles may need to suggest in other cases. For example, programming in functional style with small methods can benefit from suggesting every suitable local variable to be converted to var style. Or may be your project has IElement root interface and you just know that every variable with "element" name is IElement and you don't want explicit types for this case. Probably, any method with the name GetTreeNode() always return ITreeNode and you want vars for all such local variable.

Currently, we have two suggestions: one that suggests every suitable explicitly typed local to be converted to implicitly typed var, and another that suggests according to rules above.

So it seems there are two suggestion modes. The first suggests using the var keyword when the name of the type is obvious from the right hand side expression being evaluated such as casts or new object creation. The second mode suggests replacing type declarations with the var keyword anywhere the compiler can infer the type [which is pretty much everywhere except for a few edge cases such as when you want to initialize a variable with null at declaration]. 

The first suggestion mode makes sense to me since the code doesn't lose any clarity and it makes for shorter code. The second mode is the one I find problematic it takes information out of the equation to save a couple of characters per line of code. Each time someone is reading the code, they need to resort to using Go To Definition or Auto-Complete features of their IDE to tell something as simple as "what is the type of this object".

Unfortunately, the ReSharper developers seem to have dug in their heels religiously on this topic as can be seen in the post entitled Varification -- Using Implicitly Typed Locals where a number of arguments are made justifying always using implicitly typed variables including

• It induces better naming for local variables.
• It induces better API.
• It induces variable initialization.
• It removes code noise
• It doesn't require using directive.

It's interesting how not only are almost all of these "benefits" mainly stylistic but how they contradict each other. For example, the claim that it leads to "better naming for local variables" really means it compels developers to use LONGER HUNGARIAN STYLE VARIABLE NAMES. Funny enough, these long variable names add more noise to the code overall since they show up everywhere the variable is used compared to a single type name showing up when the variable is declared. The argument that it leads to "better API" is another variation of this theme since it argues that if you are compelled to use LONGER MORE DESCRIPTIVE PROPERTY NAMES (e.g. XmlNode.XmlNodeName instead of XmlNode.Name) then this is an improvement.  Someone should inform the ReSharper folks that encoding type information in variable names sucks, that's why we're using a strongly typed programming language like C# in the first place.

One more thing, the claim that it encourages variable initialization is weird given that the C# compiler already enforces that. More importantly, the common scenario of initializing a variable to null before it is used isn't supported by the var keyword.

In conclusion, it seems to me that someone on the ReSharper team went overboard in wanting to support the new features in C# 3.0 in their product even though in some cases using these features cause more problems than they solve. Amusingly enough, the C# 3.0 language designers foresaw this problem and put the following note in the C# language reference

Remarks: Overuse of var can make source code less readable for others. It is recommended to use var only when it is necessary, that is, when the variable will be used to store an anonymous type or a collection of anonymous types.

Case closed.

Now Playing: Mariah Carey - Side Effects (featuring Young Jeezy)

Niall Kennedy has a blog post entitled Sniff browser history for improved user experience where he describes a common-sense technique to test URLs against a Web browser’s visited page history. He writes

I first blogged about this technique almost two years ago but I will now provide even more details and example implementations.
...
A web browser such as Firefox or Internet Explorer will load the current user's browser history into memory and compare each link (anchor) on the page against the user's previous history. Previously visited links receive a special CSS pseudo-class distinction of :visited and may receive special styling.
...
Any website can test a known set of links against the current visitor's browser history using standard JavaScript.

1. Place your set of links on the page at load or dynamically using the DOM access methods.
2. Attach a special color to each visited link in your test set using finely scoped CSS.
3. Walk the evaluated DOM for each link in your test set, comparing the link's colorstyle against your previously defined value.
4. Record each link that matches the expected value.
5. Customize content based on this new information (optional).

Each link needs to be explicitly specified and evaluated. The standard rules of URL structure still apply, which means we are evaluating a distinct combination of scheme, host, and path. We do not have access to wildcard or regex definitions of a linked resource.

Niall goes on to describe the common ways one can improve the user experience on a site using this technique. I’ve been considering using this approach to reduce the excess blog flair on my weblog. It doesn’t make much sense to show people a “submit to reddit” button  if they don’t use reddit. The approach suggested in Niall’s article makes it possible for me to detect what sites a user visits and then only display relevant flair on my blog posts. Unfortunately neither of Niall’s posts on the topic provide example code which is why I’m posting this follow up to Niall’s post. Below is an HTML page that uses Javascript function to return which social bookmarking sites a viewer of a Web page actually uses based on their browser history.

             <html xmlns="http://www.w3.org/1999/xhtml"
xml:lang="en" lang="en"> <head> <title>What Social Bookmarking Sites
Do You Use?</title> <script type="text/javascript"> var bookmarking_sites
= new Array("http://programming.reddit.com", "http://www.dzone.com", "http://www.digg.com",
"http://del.icio.us", "http://www.stumbleupon.com", "http://ma.gnolia.com", "http://www.dotnetkicks.com/",
"http://slashdot.org") function DetectSites() { var testelem = document.getElementById("linktest");
var visited_sites = document.getElementById("visited_sites"); var linkColor; var isVisited
= false; for (var i = 0; i < bookmarking_sites.length; i++) { var url2test = document.createElement("a");
url2test.href = bookmarking_sites[i]; url2test.innerHTML = "I'm invisible, you can't
click me"; testelem.appendChild(url2test); if(document.defaultView){ //Mozilla linkColor
= document.defaultView.getComputedStyle(url2test,null).getPropertyValue("color");
if(linkColor == "rgb(100, 149, 237)"){ isVisited = true; } }else if(url2test.currentStyle){
//IE if(url2test.currentStyle.color == "cornflowerblue"){ isVisited = true; } } if
(isVisited) { visited_sites.innerHTML = visited_sites.innerHTML + "<a href='" +
url2test.href + "'>" + url2test.href + "</a><br>" } testelem.removeChild(url2test);
isVisited = false; } } </script> <style type="text/css"> p#linktest a:visited
{ color: CornflowerBlue } </style> </head> <body onload="DetectSites()">
<b>Social Bookmarking Sites You've Visited</b> <p id="linktest" style="visibility:hidden"
/> <p id="visited_sites" /> </body> </html> 

          

Of course, after writing the aforementioned code it occured to me run a Web search and I found that there are bits of code for doing this all over the Web in places like Jermiah Grossman’s blog (Firefox only) and GNUCITIZEN. 

At least now I have it in a handy format; cut, paste and go.

Now all I need is some free time which in which to tweak my weblogt to start using the above function instead of showing people links to services they don’t use.

Now playing: Disturbed - Numb

I’ve finally broken down and used the Extension methods feature in C# 3.0. The feature is similar to the concept of “open classes” in Ruby described in Neal Ford’s post Are Open Classes Evil? which contains the following excerpt

Open classes in dynamic languages allow you to crack open a class and add your own methods to it. In Groovy, it's done with either a Category or the Expando Meta-class (which I think is a great name). JRuby allows you to do this to Java classes as well. For example, you can add methods to the ArrayList class thusly:

require "java"

include_class "java.util.ArrayList"

list = ArrayList.new

%w(Red Green Blue).each { |color| list.add(color) }


# Add "first" method to proxy of Java ArrayList class.

class ArrayList

def first

size == 0 ? nil : get(0)

end

end

puts "first item is #{list.first}"

Here, I just crack open the ArrayList class and add a first method (which probably should have been there anyway, no?).

In my case, I added a CanonicalizedUri() method the System.Uri class because I was tired of how we had to have all sorts of special case code to deal with canonicalizing URIs because Uri.AbsoluteUri property would not represent http://www.example.com and http://www.example.com/ as the same URI and a couple of other special cases.  My extension method is shown below

/// <summary>

/// Helper class used to add extension method to the System.Uri class.

/// </summary>

public static class UriHelper

{

/// <summary>

/// Returns a the URI canonicalized in the following way. (1) if the file is a UNC or file URI then it only returns the local part.

/// (2) for Web URIs it removes trailing slashes and preceding "www."

/// </summary>

/// <param name="uri"> The URI to canonicalize </param>

/// <returns> The canonicalized URI as a string </returns>

public static string CanonicalizedUri( this Uri uri)

{

if (uri . IsFile || uri . IsUnc)

return uri . LocalPath;

UriBuilder builder = new UriBuilder (uri);

builder

. Host = (builder . Host . ToLower() . StartsWith( "www." ) ? builder . Host . Substring(4) : builder . Host);

builder

. Path = (builder . Path . EndsWith( "/" ) ? builder . Path . Substring(0, builder . Path . Length - 1) : builder . Path);

return builder . ToString() . Replace( ":" + builder . Port + "/" , "/" );

}

}

Now everywhere we used to have special case code for canonicalizing a URI, we just replace that with a call to uri.CanonicalizedUri(). It’s intoxicating how liberating it feels to be able to “fix” classes in this way.  

I have seen some complain that coupling this feature with Intellisense (i.e. method name autocomplete) leads to an overwhelming experience. Compare the following screenshots from Jessica Folser’s post using System.Linq, sometimes more isn't better which shows the difference between hitting ‘.’ on an Array with the System.Linq namespace included versus not. Note that the System.Linq namespace defines a number of extension methods for the Array class and its base classes.

WITHOUT SYSTEM.LINQ (20 methods)

I did find this disconcerting at first but I got used to it.

It should be noted that “open classes” in Ruby come with a bunch more features than extension methods in C# 3.0. For example, Ruby has remove_method and undef_method which allows developers to remove methods from a class. This is particularly useful if there is a particularly buggy or insecure method you’d rather was not used by developers in your project. Much better than simply relying on the Obsolete attribute.

One problem I had with C# is that I can’t create an extension property only methods (so my CanonicalizedUri() had to be a method not a property like Uri.AbsoluteUri).  I assume this is due to difficulty in coming up with a backwards compatible extension to the syntax for properties. Either way, it sucks. You can count me as another developer who is voting for extension properties in C# 4.0 (or whatever comes next).

Now playing:Oomp Camp - Intoxicated

Brad Fitzpatrick, founder of Livejournal, has a blog post entitled Naming twins in Python & Perl where he writes

Last night at Beau's party, one of Beau's guests mentioned he's expecting twins shortly, which is why is wife wasn't at the party.
I drunkenly suggested he name his kids two names that were anagrams of each other. I then wandered off downstairs to find such suitable names.
Because I'm supposed to be be working in Python these days, not Perl, I gathered what little Python knowledge I had and wrote out:

              #!/usr/bin/python by_anagram = {} names_file = open("dist.male.first")
for line in names_file: # lines in file look like: # WILLIAM 2.451 14.812 5 # we want
just the first field. name = (line.split())[0] letters = [letter for letter in name]
letters.sort() sorted_name = "".join(letters) if not sorted_name in by_anagram:
by_anagram[sorted_name] = [] by_anagram[sorted_name].append(name) for sorted_name
in by_anagram: if len(by_anagram[sorted_name]) < 2: continue print by_anagram[sorted_name] 
            

Not so happy with it, but it worked, and I printed out the results and brought them up to the guy

You can guess where this is going. Below is my solution in C# 3.0

            using System; using System.Linq; using System.IO; namespace Name_agram{ class Program{ static
void Main(string[] args){ var names = from line in File.ReadAllLines("dist.male.first.txt") let name = line.Split('
')[0] group name by
new string(name.ToCharArray().OrderBy(x=>x).ToArray()) into anagrams select anagrams; foreach (var list_of_names in names)
{ if (list_of_names.Count() > 1) Console.WriteLine(String.Join("
",list_of_names.ToArray())); } Console.ReadLine();
} } }

There are a ton of solutions in various languages in the comments to Brad's post. Again, it is startling to see how different an idiomatic C# 3.0 solution using LINQ is from the traditional imperative/procedural style of programming.

Now Playing: Rick James - Give It To Me Baby

A few weeks ago, I wrote a prototype for the meme tracking feature of RSS Bandit in IronPython. The code was included in my blog post A Meme Tracker In IronPython.   The script was a port of Sam Ruby's original MeMeme script which shows the most recently popular links from from a set of RSS feeds.

I was impressed with how succinct the code was in IronPython when compared to what the code eventually looked like when I ported it to C# 2.0 and integrated it into RSS Bandit. Looking over the list of new features in C# 3.0, it occurred to me that a C# 3.0 version of the script would be as concise or even more concise than the IronPython version. So I ported the script to C# 3.0 and learned a few things along the way.

I'll post something shortly that goes into some details on my perspectives on the pros and cons of the various C# 3.0 features when compared to various Python features. For now, here's the meme tracker script in C# 3.0. Comparing it to the IronPython version should provide some food for thought.

          using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text.RegularExpressions; using System.IO; using System.Xml; using System.Xml.Linq; using System.Xml.XPath; using System.Globalization; namespace Memetracker
{ enum MemeMode {
PopularInUnread, PopularInPastWeek } class RankedLink{ public
string Url { get; set;} public
double Score { get; set;
} } class Vote { public
double Weight { get; set;
} public RssItem Item
{ get; set; } public
string FeedTitle { get; set;
} } class RssItem { public
string Title { get; set;
} public DateTime Date
{ get; set; } public
bool Read { get; set;
} public string Permalink { get; set;
} public Dictionary<string, string> OutgoingLinks
{ get; set; } } class Program { static Dictionary<string, List<Vote>> all_links = new Dictionary<string, List<Vote>>(); static TimeSpan one_week = new TimeSpan(7, 0, 0, 0); static MemeMode mode = MemeMode.PopularInPastWeek; static
string cache_location = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "Temp"); static
string href_regex = @"<a[\s]+[^>]*?href[\s]?=[\s""']+(.*?)[\""']+.*?>([^<]+|.*?)?<\/a>"; static Regex regex = new Regex(href_regex); static RssItem MakeRssItem(XElement itemnode)
{ XElement link_node = itemnode.Element("link"); var permalink = (link_node == null ? "" :
link_node.Value); XElement title_node = itemnode.Element("title"); var title = (title_node == null ? "" :
title_node.Value); XElement date_node = itemnode.Element("pubDate"); var date = (date_node == null ? DateTime.Now
: DateTime.Parse(date_node.Value, null, DateTimeStyles.AdjustToUniversal)); XAttribute read_node = itemnode.XPathEvaluate("//@*[local-name()
= 'read']") as XAttribute; var read = (read_node == null ? false : Boolean.Parse(read_node.Value)); XElement desc_node = itemnode.Element("description"); //
obtain href value and link text pairs var outgoing = (desc_node == null ? regex.Matches(String.Empty)
: regex.Matches(desc_node.Value)); var outgoing_links = new Dictionary<string, string>(); //ensure
we only collect unique href values from entry by replacing list returned by regex
with dictionary if (outgoing.Count > 0)
{ foreach (Match m in outgoing)
outgoing_links[m.Groups[1].Value] = m.Groups[2].Value;
} return new RssItem()
{ Permalink = permalink, Title = title,
Date = date, Read = read,
OutgoingLinks = outgoing_links }; } static
void Main(string[] args) { if (args.Length > 0) //get
directory of RSS feeds cache_location = args[0]; if (args.Length > 1) //mode
= 0 means use only unread items, mode != 0 means use all items from past week mode = (Int32.Parse(args[1]) != 0 ? MemeMode.PopularInPastWeek
: MemeMode.PopularInUnread); Console.WriteLine("Processing
items from {0} seeking items that are {1}", cache_location, (mode == MemeMode.PopularInPastWeek ? "popular
in items from the past week" : "popular in unread
items")); //decide what filter function to use depending
on mode Func<RssItem, bool> filterFunc = null; if(mode == MemeMode.PopularInPastWeek)
filterFunc = x => (DateTime.Now - x.Date < one_week)
; else filterFunc = x => x.Read == false; //in
mode = 0 each entry linking to an item counts as a vote, in mode != 0 value of vote
depends on item age Func<RssItem, double> voteFunc = null; if(mode == MemeMode.PopularInPastWeek)
voteFunc = x => 1.0 - (DateTime.Now.Ticks - x.Date.Ticks) * 1.0 / one_week.Ticks; else voteFunc = x => 1.0; var di = new DirectoryInfo(cache_location); foreach(var fi in di.GetFiles("*.xml")){ var doc = XElement.Load(Path.Combine(cache_location,
fi.Name)); // for each
item in feed // 1. Get permalink, title, read status and date // 2. Get list of outgoing
links + link title pairs // 3. Convert above to RssItem object // 4. apply filter
to pick candidate items var items = from rssitem in (from itemnode in doc.Descendants("item") select MakeRssItem(itemnode)) where filterFunc(rssitem) select rssitem; var feedTitle = doc.XPathSelectElement("channel/title").Value; //
calculate vote for each outgoing url foreach (RssItem item in items)
{ var vote = new Vote(){
Weight=voteFunc(item), Item=item,
FeedTitle=feedTitle }; //add
a vote for each of the URLs foreach (var url in item.OutgoingLinks.Keys)
{ List<Vote> value = null; if (!all_links.TryGetValue(url, out value))
value = all_links[url] = new List<Vote>();
value.Add(vote); } }//
foreach (RssItem item in items) }// foreach(var
fi in di.GetFiles("*.xml")) //tally the votes List<RankedLink> weighted_links = new List<RankedLink>(); foreach (var link_n_votes in all_links)
{ Dictionary<string, double> site = new Dictionary<string, double>(); foreach (var vote in link_n_votes.Value)
{ double oldweight; site[vote.FeedTitle] = site.TryGetValue(vote.FeedTitle, out oldweight) ? Math.Min(oldweight,
vote.Weight): vote.Weight;
} weighted_links.Add(new RankedLink(){Score=site.Values.Sum(),
Url=link_n_votes.Key});
} weighted_links.Sort((x, y) => y.Score.CompareTo(x.Score)); //output
the results, choose link text from first item we saw story linked from Console.WriteLine("<html><body><ol>"); foreach(var rankedlink in weighted_links.GetRange(0, 10)){ var link_text = (all_links[rankedlink.Url][0]).Item.OutgoingLinks[rankedlink.Url]; Console.WriteLine("<li><a
href='{0}'>{1}</a> {2}", rankedlink.Url,
link_text, rankedlink.Score); Console.WriteLine("<p>Seen
on:"); Console.WriteLine("<ul>"); foreach (var vote in all_links[rankedlink.Url])
{ Console.WriteLine("<li>{0}:
<a href='{1}'>{2}</a></li>", vote.FeedTitle,
vote.Item.Permalink,
vote.Item.Title);
} Console.WriteLine("</ul></p></li>");
} Console.WriteLine("</ol></body></html>"); Console.ReadLine();
} } }

A few days ago I blogged about my plans to make RSS Bandit a desktop client for Google Reader. As part of that process I needed to verify that it is possible to programmatically interact with Google Reader from a desktop client in a way that provides a reasonable user experience. To this end, I wrote a command line client in IronPython based on the documentation I found at the pyrfeed Website.

The command line client isn't terribly useful on its own as a way to read your feeds but it might be useful for other developers who are trying to interact with Google Reader programmatically who would learn better from  code samples than reverse engineered API documentation.

Enjoy...

PS: Note the complete lack of error handling. I never got a hang of error handling in Python let alone going back and forth between handling errors in Python vs. handling underlying .NET/CLR errors.

          
            import
            sys
            from
            System
            import
            *
            from
            System
            .
            IO
            import
            *
            from
            System
            .
            Net
            import
            *
            from
            System
            .
            Text
            import
            *
            from
            System
            .
            Globalization
            import
            DateTimeStyles
            import
            clr
            clr
            .
            AddReference
            (
            "System.Xml"
            )
            from
            System
            .
            Xml
            import
            *
            clr
            .
            AddReference
            (
            "System.Web"
            )
            from
            System
            .
            Web
            import
            *
            ################################################################# 
            # 
            #
USAGE: ipy greader.py <Gmail username> <password> <path-to-directory-for-storing-feeds> 
            # 
            #
username & password are required 
            # feed directory
location is optional, defaults to C:\Windows\Temp\ 
            ################################################################# 
            #API
URLs 
            auth_url
            =
            rhttps://www.google.com/accounts/ClientLogin?continue=http://www.google.com&service=reader&source=Carnage4Life&Email=%s&Passwd=%s
            feed_url_prefix
            =
            rhttp://www.google.com/reader/atom/
            api_url_prefix
            =
            rhttp://www.google.com/reader/api/0/
            feed_cache_prefix
            =
            r"C:\\Windows\Temp\\"
            add_url
            =
            r"http://www.google.com/reader/quickadd"
            #enumerations 
            (
            add_label
            ,
            remove_label
            )
            =
            range
            (
            1
            ,
            3
            )
            class
            TagList
            :
            """Represents
a list of the labels/tags used in Google Reader"""
            def
            __init__
            (
            self
            ,
            userid
            ,
            labels
            )
            :
            self
            .
            userid
            =
            userid
            self
            .
            labels
            =
            labels
            class
            SubscriptionList
            :
            """Represents
a list of RSS feeds subscriptions"""
            def
            __init__
            (
            self
            ,
            modified
            ,
            feeds
            )
            :
            self
            .
            modified
            =
            modified
            self
            .
            feeds
            =
            feeds
            class
            Subscription
            :
            """Represents
an RSS feed subscription"""
            def
            __init__
            (
            self
            ,
            feedid
            ,
            title
            ,
            categories
            ,
            firstitemmsec
            )
            :
            self
            .
            feedid
            =
            feedid
            self
            .
            title
            =
            title
            self
            .
            categories
            =
            categories
            self
            .
            firstitemmsec
            =
            firstitemmsec
            def
            MakeHttpPostRequest
            (
            url
            ,
            params
            ,
            sid
            )
            :
            """Performs
an HTTP POST request to a Google service and returns the results in a HttpWebResponse
object"""
            req
            =
            HttpWebRequest
            .
            Create
            (
            url
            )
            req
            .
            Method
            =
            "POST"
            SetGoogleCookie
            (
            req
            ,
            sid
            )
            encoding
            =
            ASCIIEncoding
            (
            )
            ;
            data
            =
            encoding
            .
            GetBytes
            (
            params
            )
            req
            .
            ContentType
            =
            "application/x-www-form-urlencoded"
            req
            .
            ContentLength
            =
            data
            .
            Length
            newStream
            =
            req
            .
            GetRequestStream
            (
            )
            newStream
            .
            Write
            (
            data
            ,
            0
            ,
            data
            .
            Length
            )
            newStream
            .
            Close
            (
            )
            resp
            =
            req
            .
            GetResponse
            (
            )
            return
            resp
            def
            MakeHttpGetRequest
            (
            url
            ,
            sid
            )
            :
            """Performs
an HTTP GET request to a Google service and returns the results in an XmlDocument"""
            req
            =
            HttpWebRequest
            .
            Create
            (
            url
            )
            SetGoogleCookie
            (
            req
            ,
            sid
            )
            reader
            =
            StreamReader
            (
            req
            .
            GetResponse
            (
            )
            .
            GetResponseStream
            (
            )
            )
            doc
            =
            XmlDocument
            (
            )
            doc
            .
            LoadXml
            (
            reader
            .
            ReadToEnd
            (
            )
            )
            return
            doc
            def
            GetToken
            (
            sid
            )
            :
            """Gets
an edit token which is needed for any edit operations using the Google Reader API"""
            token_url
            =
            api_url_prefix
            +
            "token"
            req
            =
            HttpWebRequest
            .
            Create
            (
            token_url
            )
            SetGoogleCookie
            (
            req
            ,
            sid
            )
            reader
            =
            StreamReader
            (
            req
            .
            GetResponse
            (
            )
            .
            GetResponseStream
            (
            )
            )
            return
            reader
            .
            ReadToEnd
            (
            )
            def
            MakeSubscription
            (
            xmlNode
            )
            :
            """Creates
a Subscription class out of an XmlNode that was obtained from the feed list"""
            id_node
            =
            xmlNode
            .
            SelectSingleNode
            (
            "string[@name='id']"
            )
            feedid
            =
            id_node
            and
            id_node
            .
            InnerText
            or
            ''
            title_node
            =
            xmlNode
            .
            SelectSingleNode
            (
            "string[@name='title']"
            )
            title
            =
            title_node
            and
            title_node
            .
            InnerText
            or
            ''
            fim_node
            =
            xmlNode
            .
            SelectSingleNode
            (
            "string[@name='firstitemmsec']"
            )
            firstitemmsec
            =
            fim_node
            and
            fim_node
            .
            InnerText
            or
            ''
            categories
            =
            [
            MakeCategory
            (
            catNode
            )
            for
            catNode
            in
            xmlNode
            .
            SelectNodes
            (
            "list[@name='categories']/object"
            )
            ]
            return
            Subscription
            (
            feedid
            ,
            title
            ,
            categories
            ,
            firstitemmsec
            )
            def
            MakeCategory
            (
            catNode
            )
            :
            """Returns
a tuple of (label, category id) from an XmlNode representing a feed's labels that
was obtained from the feed list"""
            id_node
            =
            catNode
            .
            SelectSingleNode
            (
            "string[@name='id']"
            )
            catid
            =
            id_node
            and
            id_node
            .
            InnerText
            or
            ''
            label_node
            =
            catNode
            .
            SelectSingleNode
            (
            "string[@name='label']"
            )
            label
            =
            label_node
            and
            label_node
            .
            InnerText
            or
            ''
            return
            (
            label
            ,
            catid
            )
            def
            AuthenticateUser
            (
            username
            ,
            password
            )
            :
            """Authenticates
the user and returns a username/password combination"""
            req
            =
            HttpWebRequest
            .
            Create
            (
            auth_url
            %
            (
            username
            ,
            password
            )
            )
            reader
            =
            StreamReader
            (
            req
            .
            GetResponse
            (
            )
            .
            GetResponseStream
            (
            )
            )
            response
            =
            reader
            .
            ReadToEnd
            (
            )
            .
            split
            (
            '\n'
            )
            for
            s
            in
            response
            :
            if
            s
            .
            startswith
            (
            "SID="
            )
            :
            return
            s
            [
            4
            :
            ]
            def
            SetGoogleCookie
            (
            webRequest
            ,
            sid
            )
            :
            """Sets
the Google authentication cookie on the HttpWebRequest instance"""
            cookie
            =
            Cookie
            (
            "SID"
            ,
            sid
            ,
            "/"
            ,
            ".google.com"
            )
            cookie
            .
            Expires
            =
            DateTime
            .
            Now
            +
            TimeSpan
            (
            7
            ,
            0
            ,
            0
            ,
            0
            )
            container
            =
            CookieContainer
            (
            )
            container
            .
            Add
            (
            cookie
            )
            webRequest
            .
            CookieContainer
            =
            container
            def
            GetSubscriptionList
            (
            feedlist
            ,
            sid
            )
            :
            """Gets
the users list of subscriptions"""
            feedlist_url
            =
            api_url_prefix
            +
            "subscription/list"
            #download
the JSON-esque XML feed list 
            doc
            =
            MakeHttpGetRequest
            (
            feedlist_url
            ,
            sid
            )
            #create
subscription nodes 
            feedlist
            .
            feeds
            =
            [
            MakeSubscription
            (
            node
            )
            for
            node
            in
            doc
            .
            SelectNodes
            (
            "/object/list[@name='subscriptions']/object"
            )
            ]
            feedlist
            .
            modified
            =
            False
            def
            GetTagList
            (
            sid
            )
            :
            """Gets
a list of the user's tags"""
            taglist_url
            =
            api_url_prefix
            +
            "tag/list"
            doc
            =
            MakeHttpGetRequest
            (
            taglist_url
            ,
            sid
            )
            #get
the user id needed for creating new labels from Google system tags 
            userid
            =
            doc
            .
            SelectSingleNode
            (
            "/object/list/object/string[contains(string(.),
'state/com.google/starred')]"
            )
            .
            InnerText
            userid
            =
            userid
            .
            replace
            (
            "/state/com.google/starred"
            ,
            ""
            )
            ;
            userid
            =
            userid
            [
            5
            :
            ]
            #get
the user-defined labels 
            tags
            =
            [
            node
            .
            InnerText
            .
            Replace
            (
            "user/"
            +
            userid
            +
            "/label/"
            ,
            ""
            )
            for
            node
            in
            doc
            .
            SelectNodes
            (
            "/object/list[@name='tags']/object/string[@name='id']"
            )
            if
            node
            .
            InnerText
            .
            IndexOf
            (
            "/com.google/"
            )
            ==
            -
            1
            ]
            return
            TagList
            (
            userid
            ,
            tags
            )
            def
            DownloadFeeds
            (
            feedlist
            ,
            sid
            )
            :
            """Downloads
each feed from the subscription list to a local directory"""
            for
            feedinfo
            in
            feedlist
            .
            feeds
            :
            unixepoch
            =
            DateTime
            (
            1970
            ,
            1
            ,
            1
            ,
            0
            ,
            0
            ,
            0
            ,
            0
            ,
            DateTimeKind
            .
            Utc
            )
            oneweek_ago
            =
            DateTime
            .
            Now
            -
            TimeSpan
            (
            7
            ,
            0
            ,
            0
            ,
            0
            )
            ifmodifiedsince
            =
            oneweek_ago
            -
            unixepoch
            feed_url
            =
            feed_url_prefix
            +
            feedinfo
            .
            feedid
            +
            "?n=25&r=o&ot="
            +
            str
            (
            int
            (
            ifmodifiedsince
            .
            TotalSeconds
            )
            )
            continuation
            =
            True
            continuation_token
            =
            ''
            feedDoc
            =
            None
            while
            True
            :
            print
            "Downloading
feed at %s"
            %
            (
            feed_url
            +
            continuation_token
            )
            doc
            =
            MakeHttpGetRequest
            (
            feed_url
            +
            continuation_token
            ,
            sid
            )
            continuation_node
            =
            doc
            .
            SelectSingleNode
            (
            "//*[local-name()='continuation']"
            )
            continuation_token
            =
            continuation_node
            and
            (
            "&c="
            +
            continuation_node
            .
            InnerText
            )
            or
            ''
            if
            feedDoc
            is
            None
            :
            feedDoc
            =
            doc
            else
            :
            for
            node
            in
            doc
            .
            SelectNodes
            (
            "//*[local-name()='entry']"
            )
            :
            node
            =
            feedDoc
            .
            ImportNode
            (
            node
            ,
            True
            )
            feedDoc
            .
            DocumentElement
            .
            AppendChild
            (
            node
            )
            if
            continuation_token
            ==
            ''
            :
            break
            print
            "Saving
%s"
            %
            (
            feed_cache_prefix
            +
            feedinfo
            .
            title
            +
            ".xml"
            )
            feedDoc
            .
            Save
            (
            feed_cache_prefix
            +
            feedinfo
            .
            title
            +
            ".xml"
            )
            def
            ShowSubscriptionList
            (
            feedlist
            ,
            sid
            )
            :
            """Displays
the users list of subscriptions including the labels applied to each item"""
            if
            feedlist
            .
            modified
            :
            GetSubscriptionList
            (
            feedlist
            ,
            sid
            )
            count
            =
            1
            for
            feedinfo
            in
            feedlist
            .
            feeds
            :
            print
            "%s.
%s (%s)"
            %
            (
            count
            ,
            feedinfo
            .
            title
            ,
            [
            category
            [
            0
            ]
            for
            category
            in
            feedinfo
            .
            categories
            ]
            )
            count
            =
            count
            +
            1
            def
            Subscribe
            (
            url
            ,
            sid
            )
            :
            """Subscribes
to the specified feed URL in Google Reader"""
            params
            =
            "quickadd="
            +
            HttpUtility
            .
            UrlEncode
            (
            url
            )
            +
            "&T="
            +
            GetToken
            (
            sid
            )
            resp
            =
            MakeHttpPostRequest
            (
            add_url
            ,
            params
            ,
            sid
            )
            if
            resp
            .
            StatusCode
            ==
            HttpStatusCode
            .
            OK
            :
            print
            "%s
successfully added to subscription list"
            %
            url
            return
            True
            else
            :
            print
            resp
            .
            StatusDescription
            return
            False
            def
            Unsubscribe
            (
            index
            ,
            feedlist
            ,
            sid
            )
            :
            """Unsubscribes
from the feed at the specified index in the feed list"""
            unsubscribe_url
            =
            api_url_prefix
            +
            "subscription/edit"
            feed
            =
            feedlist
            .
            feeds
            [
            index
            ]
            params
            =
            "ac=unsubscribe&i=null&T="
            +
            GetToken
            (
            sid
            )
            +
            "&t="
            +
            feed
            .
            title
            +
            "&s="
            +
            feed
            .
            feedid
            resp
            =
            MakeHttpPostRequest
            (
            unsubscribe_url
            ,
            params
            ,
            sid
            )
            if
            resp
            .
            StatusCode
            ==
            HttpStatusCode
            .
            OK
            :
            print
            "'%s'
successfully removed from subscription list"
            %
            feed
            .
            title
            return
            True
            else
            :
            print
            resp
            .
            StatusDescription
            return
            False
            def
            Rename
            (
            new_title
            ,
            index
            ,
            feedlist
            ,
            sid
            )
            :
            """Renames
the feed at the specified index in the feed list"""
            api_url
            =
            api_url_prefix
            +
            "subscription/edit"
            feed
            =
            feedlist
            .
            feeds
            [
            index
            ]
            params
            =
            "ac=edit&i=null&T="
            +
            GetToken
            (
            sid
            )
            +
            "&t="
            +
            new_title
            +
            "&s="
            +
            feed
            .
            feedid
            resp
            =
            MakeHttpPostRequest
            (
            api_url
            ,
            params
            ,
            sid
            )
            if
            resp
            .
            StatusCode
            ==
            HttpStatusCode
            .
            OK
            :
            print
            "'%s'
successfully renamed to '%s'"
            %
            (
            feed
            .
            title
            ,
            new_title
            )
            return
            True
            else
            :
            print
            resp
            .
            StatusDescription
            return
            False
            def
            EditLabel
            (
            label
            ,
            editmode
            ,
            userid
            ,
            feedlist
            ,
            index
            ,
            sid
            )
            :
            """Adds
or removes the specified label to the feed at the specified index depending on the
edit mode"""
            full_label
            =
            "user/"
            +
            userid
            +
            "/label/"
            +
            label
            label_url
            =
            api_url_prefix
            +
            "subscription/edit"
            feed
            =
            feedlist
            .
            feeds
            [
            index
            ]
            params
            =
            "ac=edit&i=null&T="
            +
            GetToken
            (
            sid
            )
            +
            "&t="
            +
            feed
            .
            title
            +
            "&s="
            +
            feed
            .
            feedid
            if
            editmode
            ==
            add_label
            :
            params
            =
            params
            +
            "&a="
            +
            full_label
            elif
            editmode
            ==
            remove_label
            :
            params
            =
            params
            +
            "&r="
            +
            full_label
            else
            :
            return
            resp
            =
            MakeHttpPostRequest
            (
            label_url
            ,
            params
            ,
            sid
            )
            if
            resp
            .
            StatusCode
            ==
            HttpStatusCode
            .
            OK
            :
            print
            "Successfully
edited label '%s' of feed '%s'"
            %
            (
            label
            ,
            feed
            .
            title
            )
            return
            True
            else
            :
            print
            resp
            .
            StatusDescription
            return
            False
            def
            MarkAllItemsAsRead
            (
            index
            ,
            feedlist
            ,
            sid
            )
            :
            """Marks
all items from the selected feed as read"""
            unixepoch
            =
            DateTime
            (
            1970
            ,
            1
            ,
            1
            ,
            0
            ,
            0
            ,
            0
            ,
            0
            ,
            DateTimeKind
            .
            Utc
            )
            markread_url
            =
            api_url_prefix
            +
            "mark-all-as-read"
            feed
            =
            feedlist
            .
            feeds
            [
            index
            ]
            params
            =
            "s="
            +
            feed
            .
            feedid
            +
            "&T="
            +
            GetToken
            (
            sid
            )
            +
            "&ts="
            +
            str
            (
            int
            (
            (
            DateTime
            .
            Now
            -
            unixepoch
            )
            .
            TotalSeconds
            )
            )
            MakeHttpPostRequest
            (
            markread_url
            ,
            params
            ,
            sid
            )
            print
            "All
items in '%s' have been marked as read"
            %
            feed
            .
            title
            def
            GetFeedIndexFromUser
            (
            feedlist
            )
            :
            """prompts
the user for the index of the feed they are interested in and returns the index as
the result of this function"""
            print
            "Enter
the numeric position of the feed from 1 - %s"
            %
            (
            len
            (
            feedlist
            .
            feeds
            )
            )
            index
            =
            int
            (
            sys
            .
            stdin
            .
            readline
            (
            )
            .
            strip
            (
            )
            )
            if
            (
            index
            <
            1
            )
            or
            (
            index
            >
            len
            (
            feedlist
            .
            feeds
            )
            )
            :
            print
            "Invalid
index specified: %s"
            %
            feed2label_indx
            return
            -
            1
            else
            :
            return
            index
            if
            __name__
            ==
            "__main__"
            :
            if
            len
            (
            sys
            .
            argv
            )
            <
            3
            :
            print
            "ERROR:
Please specify a Gmail username and password"
            else
            :
            if
            len
            (
            sys
            .
            argv
            )
            >
            3
            :
            feed_cache_prefix
            =
            sys
            .
            argv
            [
            3
            ]
            SID
            =
            AuthenticateUser
            (
            sys
            .
            argv
            [
            1
            ]
            ,
            sys
            .
            argv
            [
            2
            ]
            )
            feedlist
            =
            SubscriptionList
            (
            True
            ,
            [
            ]
            )
            GetSubscriptionList
            (
            feedlist
            ,
            SID
            )
            taglist
            =
            GetTagList
            (
            SID
            )
            options
            =
            "***Your
options are (f)etch your feeds, (l)ist your subscriptions, (s)ubscribe to a new feed,
(u)nsubscribe, (m)ark read , (r)ename, (a)dd a label to a feed, (d)elete a label from
a feed or (e)xit***"
            print
            "\n"
            while
            True
            :
            print
            options
            cmd
            =
            sys
            .
            stdin
            .
            readline
            (
            )
            if
            cmd
            ==
            "e\n"
            :
            break
            elif
            cmd
            ==
            "l\n"
            :
            #list
subscriptions
            ShowSubscriptionList
            (
            feedlist
            ,
            SID
            )
            elif
            cmd
            ==
            "s\n"
            :
            #subscribe
to a new feed
            print
            "Enter
url: "
            new_feed_url
            =
            sys
            .
            stdin
            .
            readline
            (
            )
            .
            strip
            (
            )
            success
            =
            Subscribe
            (
            new_feed_url
            ,
            SID
            )
            if
            feedlist
            .
            modified
            ==
            False
            :
            feedlist
            .
            modified
            =
            success
            elif
            cmd
            ==
            "u\n"
            :
            #unsubscribe
from a feed
            feed2remove_indx
            =
            GetFeedIndexFromUser
            (
            feedlist
            )
            if
            feed2remove_indx
            !=
            -
            1
            :
            success
            =
            Unsubscribe
            (
            feed2remove_indx
            -
            1
            ,
            feedlist
            ,
            SID
            )
            if
            feedlist
            .
            modified
            ==
            False
            :
            feedlist
            .
            modified
            =
            success
            elif
            cmd
            ==
            "r\n"
            :
            #rename
a feed
            feed2rename_indx
            =
            GetFeedIndexFromUser
            (
            feedlist
            )
            if
            feed2rename_indx
            !=
            -
            1
            :
            print
            "'%s'
selected"
            %
            feedlist
            .
            feeds
            [
            feed2rename_indx
            -
            1
            ]
            .
            title
            print
            "Enter
the new title for the subscription:"
            success
            =
            Rename
            (
            sys
            .
            stdin
            .
            readline
            (
            )
            .
            strip
            (
            )
            ,
            feed2rename_indx
            -
            1
            ,
            feedlist
            ,
            SID
            )
            if
            feedlist
            .
            modified
            ==
            False
            :
            feedlist
            .
            modified
            =
            success
            elif
            cmd
            ==
            "f\n"
            :
            #fetch
feeds
            feedlist
            =
            DownloadFeeds
            (
            feedlist
            ,
            SID
            )
            elif
            cmd
            ==
            "m\n"
            :
            #mark
all items as read
            feed2markread_indx
            =
            GetFeedIndexFromUser
            (
            feedlist
            )
            if
            feed2markread_indx
            !=
            -
            1
            :
            MarkAllItemsAsRead
            (
            feed2markread_indx
            -
            1
            ,
            feedlist
            ,
            SID
            )
            elif
            (
            cmd
            ==
            "a\n"
            )
            or
            (
            cmd
            ==
            "d\n"
            )
            :
            #add/remove
a label on a feed
            editmode
            =
            (
            cmd
            ==
            "a\n"
            )
            and
            add_label
            or
            remove_label
            feed2label_indx
            =
            GetFeedIndexFromUser
            (
            feedlist
            )
            if
            feed2label_indx
            !=
            -
            1
            :
            feed
            =
            feedlist
            .
            feeds
            [
            feed2label_indx
            -
            1
            ]
            print
            "'%s'
selected"
            %
            feed
            .
            title
            print
            "%s"
            %
            (
            (
            cmd
            ==
            "a\n"
            )
            and
            "Enter
the new label:"
            or
            "Enter
the label to delete:"
            )
            label_name
            =
            sys
            .
            stdin
            .
            readline
            (
            )
            .
            strip
            (
            )
            success
            =
            EditLabel
            (
            label_name
            ,
            editmode
            ,
            taglist
            .
            userid
            ,
            feedlist
            ,
            feed2label_indx
            -
            1
            ,
            SID
            )
            if
            feedlist
            .
            modified
            ==
            False
            :
            feedlist
            .
            modified
            =
            success
            else
            :
            print
            "Unknown
command"
            
            
          
        

Now Playing: DJ Drama - Cannon (Remix) (Feat. Lil Wayne, Willie The Kid, Freeway And T.I.)

REQUEST:

POST /reader/api/0/subscription/edit HTTP/1.1
Content-Type: application/x-www-form-urlencoded
Host: www.google.com
Cookie: SID=DQAAAHoAAD4SjpLSFdgpOrhM8Ju-JL2V1q0aZxm0vIUYa-p3QcnA0wXMoT7dDr7c5FMrfHSZtxvDGcDPTQHFxGmRyPlvSvrgNe5xxQJwPlK_ApHWhzcgfOWJoIPu6YuLAFuGaHwgvFsMnJnlkKYtTAuDA1u7aY6ZbL1g65hCNWySxwwu__eQ
Content-Length: 182
Expect: 100-continue

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Date: Sun, 30 Dec 2007 23:08:51 GMT
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<table><tr><td rowspan="3" width="1%"><b><font face="times" color="#0039b6" size="10">G</font><font face="times" color="#c41200" size="10">o</font><font face="times" color="#f3c518" size="10">o</font><font face="times" color="#0039b6" size="10">g</font><font face="times" color="#30a72f" size="10">l</font><font face="times" color="#c41200" size="10">e</font>&nbsp;&nbsp;</b></td>
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<blockquote><h1>Server Error</h1>
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<p></p></blockquote>
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This time last year, Erik Meijer sent me a paper about a new programming language project he was working on. I was high on the social graph at that time and didn't get around to responding to Erik's paper until this fall. The premise seemed fundamentally interesting; create an MSIL to Javascript compiler which is conceptually similar to Google's GWT and Nikhil Kothari's Script# then flip the traditional Web development script by allowing developers to choose whether code runs on the server or on the client by simply decorating methods with attributes. The last bit is the interesting innovation in Erik's project although it is obscured by the C#/VB/MSIL to Javascript compiler aspects.

As an example, let's say you have a function like ValidateAddress(). Whether this logic lives on the client (i.e. Javascript in the browser) or runs on the server is really a function of how complicated that function actually ends up being. Now imagine if when the time comes to refactor the function and move the validation logic from the Web client to the server or vice versa, instead of rewriting Javascript code in C#/IronPython/VB.NET/IronRuby/etc or vice versa you just add or remove a [RunAtOrigin] attribute on the function.

This project shipped last week as Microsoft Volta. You can learn a little more about it in Erik Meijer's post on Lambda the Ultimate entitled Democratizing the Cloud using Microsoft Live Labs Volta. Try it out, it's an interesting project that has legs. 

Now playing: Jay-Z - Pray

One of the things that has always frustrated me about programming in C# that it is such a hassle to return multiple values from a method. You either have to create a wrapper class whose entire purpose is to hold two or three variables or even worse use ref or out parameters. I used to get around this problem in C++ by using the pair utility class since I often wanted to deal with an object plus some value associated with it. However this approach quickly breaks down when you have more than two objects you want to associate temporarily for some processing.  

For example, in the Top Stories feature of RSS Bandit I have some code that operates on a URL, its weighted score and a list of all the posts that reference it. In C#, there’s no good way to deal with those three objects as a single entity without wrapping them in a class definition. In Python, it’s quite easy to do that using tuples. Compare the following two blocks of code and notice how I don’t need the RelationHrefEntry and RankedNewsItem types in the Python version of the code

C#:     /* Tally the votes, only 1 vote counts per feed */

              

 //RelationHrefEntry is (Href, Score, References),
RankedNewsItem is (NewsItem, Score)
              

                List
                <
                RelationHRefEntry
                >
                 weightedLinks 
                =
                
                
                new
                
                
                List
                <
                RelationHRefEntry
                >
                ();

              
              

                foreach
                 (
                KeyValuePair
                <
                RelationHRefEntry
                , 
                List
                <
                RankedNewsItem
                >>
                 linkNvotes 
                in
                 allLinks)
{ 

              
              

                 Dictionary
                <
                string
                , 
                float
                >
                 votesPerFeed 
                =
                
                
                new
                
                
                Dictionary
                <
                string
                , 
                float
                >
                (); 

              
              

              
              

                 //pick the lower vote if multiple links from a particular
feed
                
                
              
              

                 foreach
                 (
                RankedNewsItem
                 voteItem 
                in
                 linkNvotes
                .
                Value)
{ 

              
              

                 string
                 feedLink 
                =
                 voteItem
                .
                Item
                .
                FeedLink;

              
              

                 if
                (votesPerFeed
                .
                ContainsKey(feedLink)){ 

              
              

votesPerFeed[feedLink] =Math.Min(votesPerFeed[feedLink],
voteItem.Score); 

              

}else{ 

              

votesPerFeed.Add(feedLink, voteItem.Score); 

              

linkNvotes.Key.References.Add(voteItem.Item); 

              

} 

              

} 

              

                 float
                 totalScore 
                =
                 0.0f;

              
              

                 foreach
                 (
                float
                 value 
                in
                 votesPerFeed
                .
                Values)
{ 

              
              

totalScore += value; 

              

} 

              

linkNvotes.Key.Score = totalScore; 

              

weightedLinks.Add(linkNvotes.Key); 

              

}

              

weightedLinks.Sort(delegate(RelationHRefEntry x, RelationHRefEntry y)
{ return y.Score.CompareTo(x.Score);}
); 

              

weightedLinks = weightedLinks.GetRange(0,
numStories);

            

Python:

              

    # tally the votes, only 1 vote counts per
feed

    weighted_links = []

    for link, votes in all_links.items():

        site = {}

        for weight, item, feedTitle in votes:   #tuple
magic happens here             


            site[feedTitle]
= min(site.get(feedTitle,1), weight)   #Python
dictionaries are smarter than .NET’s 

        weighted_links.append((sum(site.values()),
link))   #more tuple magic, no need for manual
summing of values 

    weighted_links.sort()

    weighted_links.reverse()

            

Now playing: UGK - One Day

My weekend project was to read Dive Into Python and learn enough Python to be able to port Sam Ruby's meme tracker (source code) from CPython to Iron Python. Sam's meme tracker, shows the most popular links from the past week from the blogs in his RSS subscriptions. A nice wrinkle Sam added to his code is that more recent posts are weighted higher than older posts. So a newly hot item with 3 or 4 links posted yesterday ends up ranking higher than an item with 6 to 10 posts about it from five days ago. Using that sort of weighting probably wouldn't have occurred to me if I just hacked the feature on my own, so I'm glad I spent the time learning Sam's code.

There are a few differences between Sam's code and mine, the most significant being that I support two modes; showing the most popular items from all unread posts and showing the most popular items from the past week. The other differences mainly have to do with the input types (Atom entries vs. RSS feeds) and using .NET Libraries like System.Xml and System.IO instead of CPython libraries like libxml2 and blob. You can see the difference between both approaches for determining top stories on my feed subscriptions below

Top Stories in the Past Week

1. Mobile Web: So Close Yet So Far (score: 1.71595943656)
2. The Secret Strategies Behind Many "Viral" Videos (score: 1.52423410473)
3. Live Documents is Powerful Stuff (score: 1.35218082421)

Top Stories in all Unread Posts

1. OpenSocial (score: 5.0)
2. The Future of Reading (score: 3.0)
3. MySpace (score: 3.0) [Ed Note:Mostly related to OpenSocial]

As you can probably tell, the weighted scoring isn't used when determining top stories in all unread posts. I did this to ensure that the results didn't end up being to similar for both approaches. This functionality is definitely going to make its way into RSS Bandit now that I've figured out the basic details on how it should work. As much as I'd like to keep this code in Iron Python, I'll probably port it to C# when integrating it for a number of practical reasons including maintainability (Torsten shouldn't have to learn Python as well), performance and better integration into our application.

Working with Python was a joy. I especially loved programming with a REPL. If I had a question about what some code does, it's pretty easy to write a few one or two liners to figure it out. Contrast this with  using Web searches, trawling through MSDN documentation or creating a full blown program just to test the out some ideas when using C# and Visual Studio. I felt a lot more productive even though all I was using was Emacs and a DOS prompt. 

I expected the hardest part of my project to be getting my wife to tolerate me spending most of the weekend hacking code. That turned out not to be a problem because it didn't take as long as I expected and for the most part we did spend the time together (me on the laptop, her reading The Other Boleyn Girl, both of us on the sofa). 

There are at least two things that need some fine tuning. The first is that I get the title of the link from the text of the links used to describe it and that doesn't lead to very useful link text in over half of the cases. After generating the page, there may need to be a step that goes out to the HTML pages and extracts their title elements for use as link text. The second problem is that popular sites like Facebook and Twitter tend to show up every once in a while in the list just because people talk about them so much. This seems to happen less than I expected however, so this may not be a problem in reality.

Now I just have to worry about whether to call the button [Show Popular Stories] or [Show Most Linked Stories]. Thoughts?

import time, sys, re, System, System.IO, System.Globalization
from System import *
from System.IO import *
from System.Globalization import DateTimeStyles
import clr
clr.AddReference("System.Xml")
from System.Xml import *

#################################################################
#
# USAGE: ipy memetracker.py <directory-of-rss-feeds> <mode>
# mode = 0 show most popular links in unread items
# mode = 1 show most popular links from items from the past week
#################################################################

all_links = {}
one_week =  TimeSpan(7,0,0,0)

cache_location = r"C:\Documents and Settings\dareo\Local Settings\Application Data\RssBandit\Cache"
href_regex     = r"<a[\s]+[^>]*?href[\s]?=[\s\"\']+(.*?)[\"\']+.*?>([^<]+|.*?)?<\/a>"
regex          = re.compile(href_regex)

(popular_in_unread, popular_in_past_week) = range(2)
mode = popular_in_past_week

class RssItem:
    """Represents an RSS item"""
    def __init__(self, permalink, title, date, read, outgoing_links):
        self.outgoing_links = outgoing_links
        self.permalink      = permalink
        self.title          = title
        self.date           = date
        self.read           = read

def MakeRssItem(itemnode):
    link_node  = itemnode.SelectSingleNode("link")
    permalink  = link_node and link_node.InnerText or ''
    title_node = itemnode.SelectSingleNode("title")
    title      = link_node and title_node.InnerText or ''
    date_node  = itemnode.SelectSingleNode("pubDate")
    date       = date_node and DateTime.Parse(date_node.InnerText, None, DateTimeStyles.AdjustToUniversal) or DateTime.Now 
    read_node  = itemnode.SelectSingleNode("//@*[local-name() = 'read']")
    read       = read_node and int(read_node.Value) or 0
    desc_node  = itemnode.SelectSingleNode("description")
    # obtain href value and link text pairs
    outgoing   = desc_node and regex.findall(desc_node.InnerText) or []
    outgoing_links = {}
    #ensure we only collect unique href values from entry by replacing list returned by regex with dictionary
    if len(outgoing) > 0:
        for url, linktext in outgoing:
            outgoing_links[url] = linktext
    return RssItem(permalink, title, date, read, outgoing_links)   

if __name__ == "__main__":
    if len(sys.argv) > 1: #get directory of RSS feeds
        cache_location = sys.argv[1]
    if len(sys.argv) > 2: # mode = 0 means use only unread items, mode = 1 means use all items from past week
        mode           = int(argv[2]) and popular_in_past_week or popular_in_unread

    print "Processing items from %s seeking items that are %s" % (cache_location,
                                                                  mode and "popular in items from the past week"
                                                                  or "popular in unread items" )
    #decide what filter function to use depending on mode
    filterFunc = mode and (lambda x : (DateTime.Now - x.date) < one_week) or (lambda x : x.read == 0)
    #in mode = 0 each entry linking to an item counts as a vote, in mode = 1 value of vote depends on item age
    voteFunc   = mode and (lambda x: 1.0 - (DateTime.Now.Ticks - x.date.Ticks) * 1.0 / one_week.Ticks) or (lambda x: 1.0)

    di = DirectoryInfo(cache_location)
    for fi in di.GetFiles("*.xml"):     
        doc = XmlDocument()
        doc.Load(Path.Combine(cache_location, fi.Name))
        # for each item in feed       
        #  1. Get permalink, title, read status and date
        #  2. Get list of outgoing links + link title pairs
        #  3. Convert above to RssItem object
        items = [ MakeRssItem(node) for node in doc.SelectNodes("//item")]
        feedTitle = doc.SelectSingleNode("/rss/channel/title").InnerText
        # apply filter to pick candidate items, then calculate vote for each outgoing url
        for item in filter(filterFunc, items):
            vote = (voteFunc(item), item, feedTitle)
            #add a vote for each of the URLs
            for url in item.outgoing_links.Keys:
                if all_links.get(url) == None:
                    all_links[url] = []
                all_links.get(url).append(vote)

       # tally the votes, only 1 vote counts per feed
    weighted_links = []
    for link, votes in all_links.items():
        site = {}
        for weight, item, feedTitle in votes:               
            site[feedTitle] = min(site.get(feedTitle,1), weight)
        weighted_links.append((sum(site.values()), link))
    weighted_links.sort()
    weighted_links.reverse()

    # output the results, choose link text from first item we saw story linked from
    print "<ol>"   
    for weight, link in weighted_links[:10]:
        link_text = (all_links.get(link)[0])[1].outgoing_links.get(link)
        print "<li><a href='%s'>%s</a> (%s)" % (link, link_text, weight)
        print "<p>Seen on:"
        print "<ul>"
        for weight, item, feedTitle in all_links.get(link):
            print "<li>%s: <a href='%s'>%s</a></li>" % (feedTitle, item.permalink, item.title)
        print "</ul></p></li>" 
    print "</ol>"

I've been reading Dive Into Python for a couple of days have gotten far enough to tell what the following block of code does if the object variable is an arbitrary Python object

methodList = [method for method in dir(object) if callable(getattr(object, method))]
    processFunc = collapse and (lambda s: " ".join(s.split())) or (lambda s: s)
    print "\n".join(["%s %s" %
                      (method.ljust(spacing),
                       processFunc(str(getattr(object, method).__doc__)))
                     for method in methodList])

However I've been having a tougher time than I expected with learning Python using Dive Into Python for a couple of reasons, some to do with how the book is laid out and some to do with my choice of IronPython as my Python implementation of choice. The main problems I've been having are

• IronPython doesn't have a number of standard libraries that are used in the book such as os, xml.dom, UserDict, sgmllib and so on. This means I can't construct or run a number of the more advanced samples in the book.
• The book seems to dive into meaty topics before covering the basics. For example, introspection (aka reflection) and lambda functions (aka anonymous methods)  are covered in Chapter 4 while defining classes and importing modules is covered in Chapter 5. Similarly, a discussion on for loops seems to have been removed from the most recent version of the book and replaced with a discussion on list comprehensions which are definitely superior but more alien to the novice.
• I tend to learn comparatively. Thus I would love to get a more direct mapping of constructs in C# to those in Python with  discussions on Python features that don't exist in C#. This is the tack I took with C# from a Java Developers perspective and it seems a lot of people found that useful.

For these reasons, I thought it would be useful to create a set of tutorials for myself that would address some of these issues I've been having. Then I wondered if other C# developers wouldn't find such an article or tutorial useful as well. Are there any C# developers out there that would actually be interested in this or am I an edge case?

PS: I wouldn't expect to get time to actually writing, editing and publishing such tutorials until the summer of next year at the earliest (which I expect should coincide with the availability of IronPython 2.0). 

I’ve been working on simplifying my life and improving on my mental state over the last year or so. I’m now at the stage where I think I’ve gotten into a decent routine with diet and excercise. My next step [now that the rigors of buying the house and planning the wedding are over] is to broaden my programming horizons by learning a radically different programming language from my comfort zone, Python and C# respectively, while not harming my personal life or work habits.

It turns out that I can add an hour or two to my day by (i) leaving home earlier and thus avoiding traffic (ii) reading blogs less (iii) unsubscribing from most of the Microsoft internal mailing lists I was on and (iv) scheduling meetings so they are clumped together instead of having three meetings with 30 minutes in between each one thus burning up an hour of my time mentally twiddling my thumbs and checking email. 

So far I’ve installed IronPython and python-mode. I’ve also started reading Dive into Python and have gotten as far as Chapter 3. I’d just like to thank folks like Mark Pilgrim, Jim Hugunin and Barry Warsaw who are gifting programmers with such wonderful resources. Right now I’m still trying to wrap my mind around Everything is An Object

Everything in Python is an object, and almost everything has attributes and methods.

This is so important that I'm going to repeat it in case you missed it the first few times: everything in Python is an object. Strings are objects. Lists are objects. Functions are objects. Even modules are objects.

All functions have a built-in attribute __doc__, which returns the doc string defined in the function's source code. The sys module is an object which has (among other things) an attribute called path. And so forth.

So far this is already an enjoyable experience for someone who has mostly been programming in Javascript (not object oriented, dynamic but weakly typed) and C# (statically typed, no REPL) for the past few years.

Once I’m done reading Dive into Python, my plan is to integrate Sam Ruby’s MeMeme 2.0 into RSS Bandit. That way even though I’ve stopped reading blogs regularly, I don’t end up finding out days later that Visual Studio 2008 and .NET Framework 3.5 were released because it wasn’t on TechMeme or programming.reddit.  

Optimizing your life by writing code is fun. I guess this is what they call life hacking.

Now playing: The Clash - Rock The Casbah

I recently got an email from a developer about my post Thoughts on Amazon's Internal Storage System (Dynamo) which claimed that I seem to be romanticizing distributed systems that favor availability over consistency. He pointed out that although this sounds nice on paper, it places a significant burden on application developers. He is 100% right. This has been my experience in Windows Live and I’ve heard enough second hand to assume it is the experience at Amazon as well when it comes to Dynamo.

I thought an example of how this trade-off affects developers would be a useful excercise and may be of interest to my readers. The following example is hypothetical and should not be construed as describing the internal architectures of any production systems I am aware of.

Scenario: Torsten Rendelmann, a Facebook user in Germany, accepts a friend request from Dare Obasanjo who is a Facebook user in the United States.

The Distributed System: To improve the response times for users in Europe, imagine Facebook has a data center in London while American users a serviced from a Data Center in Palo Alto. To achieve this, the user database is broken up in a process commonly described as sharding. The question of if and how data is replicated across both data centers isn’t relevant to this example.

The application developer who owns the confirm_friend_request() method, will ideally want to write code that took the following form 

public void confirm_friend_request(user1, user2){

  begin_transaction();
  update_friend_list(user1, user2, status.confirmed); //palo alto
  update_friend_list(user2, user1, status.confirmed); //london
  end_transaction();

} 

Yay, distributed transactions. You have to love a feature that every vendor advises you not to use if you care about performance. So obviously this doesn’t work for a large scale distributed system where performance and availabilty are important.  

Things get particularly ugly when you realize that either data center or the specific server a user’s data is stored on could be unreachable for a variety of reasons (e.g. DoS attack, high seasonal load, drunk sys admin tripped over a power cord, hard drive failure due to cheap components, etc).

There are a number of options one can consider when availability and high performance are considered to be more important than data consistency in the above example. Below are three potential implementations of the code above each with it’s own set of trade offs.

OPTION I: Application developer performs manual rollback on error

public void confirm_friend_request_A(user1, user2){

 try{
   update_friend_list(user1, user2, status.confirmed); //palo alto 
 }catch(exception e){ 
  report_error(e); 
  return;
 }

 try{
  update_friend_list(user2, user1, status.confirmed); //london
 }catch(exception e) {
  revert_friend_list(user1, user2);
  report_error(e);
  return; 
 }

}

The problem here is that we don’t handle the case where revert_friend_list() fails. This means that Dare (user1) may end up having Torsten (user2) on his friend list but Torsten won’t have Dare on his friend list. The database has lied.

OPTION II: Failed events are placed in a message queue to be retried until they succeed.   

public void confirm_friend_request_B(user1, user2){

 try{
   update_friend_list(user1, user2, status.confirmed); //palo alto 
 }catch(exception e){ 
  report_error(e); 
  add_to_retry_queue(operation.updatefriendlist, user1, user2, current_time()); 
 }

 try{
  update_friend_list(user2, user1, status.confirmed); //london
 }catch(exception e) {
  report_error(e); 
  add_to_retry_queue(operation.updatefriendlist, user2, user1, current_time());  
 }

}

Depending on how long the error exists and how long it takes an item to sit in the message queue, there will be times when the Dare (user1) may end up having Torsten (user2) on his friend list but Torsten won’t have Dare on his friend list. The database has lied, again.

OPTION III: System always accepts updates but application developers may have to resolve data conflicts later. (The Dynamo approach)

/* update_friend_list always succeeds but may enqueue an item in message queue to try again later in the event of failure. This failure is not propagated to callers of the method.  */

public void confirm_friend_request_C(user1, user2){
   update_friend_list(user1, user2, status.confirmed); // palo alto
   update_friend_list(user2, user1, status.confirmed); //london 

}

/* get_friends() method has to reconcile results returned by get_friends() because there may be data inconsistency due to a conflict because a change that was applied from the message queue is contradictory to a subsequent change by the user.  In this case, status is a bitflag where all conflicts are merged and it is up to app developer to figure out what to do. */ 

  public list get_friends(user1){ 
      list actual_friends = new list();
      list friends = get_friends();  

      foreach (friend in friends){     

        if(friend.status == friendstatus.confirmed){ //no conflict
           actual_friends.add(friend);

        }else if((friend.status &= friendstatus.confirmed) 
                   and !(friend.status &= friendstatus.deleted)){

          // assume friend is confirmed as long as it wasn’t also deleted
          friend.status = friendstatus.confirmed;              
          actual_friends.add(friend); 
          update_friends_list(user1, friend, status.confirmed);

        }else{ //assume deleted if there is a conflict with a delete
          update_friends_list( user1, friend, status.deleted)
        }

      }//foreach

   return actual_friends;
}

These are just a few of the many approaches that can be implemented in such a distributed system to get around the performance and availability implications of using distributed transactions. The main problem with them is that in every single case, the application developer has an extra burden placed on his shoulders due to inherent fragility of distributed systems. For a lot of developers, the shock of this realization is akin to the shock of programming in C++ after using C# or Ruby for a couple of years. Manual memory management? Actually having to perform bounds checking arrays? Being unable to use decades old technology like database transactions?

The challenge in building a distributed storage system like BigTable or Dynamo is in balancing the need for high availability and performance while not building a system that encourages all sorts of insidious bugs to exist in the system by design.  Some might argue that Dynamo goes to far in the burden that it places on developers while there are others that would argue that it doesn’t go far enough.

In what camp do you fall?

Now playing: R. Kelly - Rock Star (feat. Ludacris & Kid Rock)

Scott Guthrie has a blog post entitled Releasing the Source Code for the .NET Framework Libraries where he writes

One of the things my team has been working to enable has been the ability for .NET developers to download and browse the source code of the .NET Framework libraries, and to easily enable debugging support in them.

Today I'm excited to announce that we'll be providing this with the .NET 3.5 and VS 2008 release later this year.

We'll begin by offering the source code (with source file comments included) for the .NET Base Class Libraries (System, System.IO, System.Collections, System.Configuration, System.Threading, System.Net, System.Security, System.Runtime, System.Text, etc), ASP.NET (System.Web), Windows Forms (System.Windows.Forms), ADO.NET (System.Data), XML (System.Xml), and WPF (System.Windows).  We'll then be adding more libraries in the months ahead (including WCF, Workflow, and LINQ).  The source code will be released under the Microsoft Reference License (MS-RL).

This is one of those announcements I find hard to get excited about. Any developer who’s been frustrated by the weird behavior of a .NET Framework class and has wanted to look at it’s code, should already know about Lutz Roeder’s Reflector which is well known in the .NET devoper community. So I’m not sure who this anouncement is actually intended to benefit.

On the other hand, I’m sure Java developers are having a chuckle at our expense that it took this long for Microsoft to allow developers to see the source code for ArrayList.Count so we can determine if it is lazily or eagerly evaluated.

Oh well, better late than never.

PS: The ability to debug into .NET Framework classes will be nice. I’ve wanted this more than once while working on RSS Bandit and will definitely take advantage of it if I ever get around to installing VS 2008.

Now playing: TLC - Somethin Wicked This Way Comes (feat. Andre 3000)

From the documentation for Directory.GetFiles Method (String, String)

When using the asterisk wildcard character in a searchPattern, such as "*.txt", the matching behavior when the extension is exactly three characters long is different than when the extension is more or less than three characters long. A searchPattern with a file extension of exactly three characters returns files having an extension of three or more characters, where the first three characters match the file extension specified in the searchPattern. A searchPattern with a file extension of one, two, or more than three characters returns only files having extensions of exactly that length that match the file extension specified in the searchPattern.

I realize this behavior is probably well known to Windows developers, but seriously, WTF? How do I match on three character file extensions (i.e. the majority of file extensions) without getting cruft as well (e.g. matching on .cpp files without getting Emacs backups with .cpp~ file extensions)?

Now playing: Mystikal - I Smell Smoke

In my previous post, I mentioned that I'm in the early stages of building an application on the Facebook platform. I haven't yet decided on an application but for now, let's assume that it is a Favorite Comic Books application which allows me to store my favorite comic books and shows me to most popular comic books among my friends.

After investigating using Amazon's EC2 + S3 to build my application I've decided that I'm better off using a traditional hosting solution running either a on the LAMP or WISC platform. One of the things I've been looking at is which platform has better support for providing an in-memory caching solution that works well in the context of a Web farm (i.e. multiple Web servers) out of the box. While working on the platforms behind several high traffic Windows Live services I've learned  that you should be prepared for dealing with scalability issues and caching is one of the best ways to get bang for the buck when improving the scalability of your service.

I recently discovered memcached which is a distributed, object caching system originally developed by Brad Fitzpatrick of LiveJournal fame. You can think of memcached as a giant hash table that can run on multiple servers which automatically handles maintaining the balance of objects hashed to each server and transparently fetches/removes objects from over the network if they aren't on the same machine that is accessing an object in the hash table. Although this sounds fairly simple, there is a lot of grunt work in building a distributed object cache which handles data partitioning across multiple servers and hides the distributed nature of the application from the developer. memcached is a well integrated into the typical LAMP stack and is used by a surprising number of high traffic websites including Slashdot, Facebook, Digg, Flickr and Wikipedia. Below is what C# code that utilizes memcached would look like sans exception handling code

public ArrayList GetFriends(int user_id){

    ArrayList friends = (ArrayList) myCache.Get("friendslist:"+ userid);

    if(friends == null){
        // Open the connection
        dbConnection.Open();

        SqlCommand cmd =new SqlCommand("select friend_id from friends_list where owner_id="+"user_id", dbConnection);

        SqlDataReader reader = cmd.ExecuteReader();

        // Add each friend ID to the list
        while (reader.Read()){
            friends.Add(rdr[0]);
        }

             reader.Close();
            

       dbConnection.Close();       
    
     

        myCache.Set("friendslist:"+ userid, friends);
    }

    return friends;
}

public void AddFriend(int user_id, int new_friends_id){

    // Open the connection
    dbConnection.Open();

             SqlCommand
cmd =new SqlCommand("insert
into friends_list (owner_id, friend_id) values ("+ user_id +","+ new_friend_id ")";
            

   cmd.ExecuteNonQuery();

    //remove key from cache since friends list has been updated
    myCache.Delete("friendslist:"+ userid);

    dbConnection .Close(); 
}

The benefits of the using of the cache should be pretty obvious. I no longer need to hit the database after the first request to retrieve the user's friend list which means faster performance in servicing the request and less I/O.  The memcached automatically handles purging items out of the cache when it hits the size limit and also deciding which cache servers should hold individual key<->value pairs.

I hang with a number of Web developers on the WISC platform and I don't think I've ever heard anyone mention memcached or anything like it.In fact I couldn't find a mention of it on Microsoft employee blogs, ASP.NET developer blogs or on MSDN. So I wondered what the average WISC developer uses as their in-memory caching solution.

After looking around a bit, I came to the conclusion that most WISC developers use the built-in ASP.NET caching features. ASP.NET provides a number of in-memory caching features including a Cache class which provides a similar API to memcached, page directives for caching portions of the page or the entire page and the ability to create dependencies between cached objects and the files or database tables/rows that they were populated from via the CacheDependency and SqlCacheDependency classes. Although some of these features are also available in various Open Source web development frameworks such as Ruby on Rails + memcached, none give as much functionality out of the box as ASP.NET or so it seems.

Below is what the code for the GetFriends and AddFriend methods would look like using the built-in ASP.NET caching features

public ArrayList GetFriends(int user_id){

    ArrayList friends = (ArrayList) Cache.Get("friendslist:"+ userid);

    if(friends == null){
        // Open the connection
        dbConnection.Open();

        SqlCommand cmd =new SqlCommand("select friend_id from friends_list where owner_id="+"user_id", dbConnection);

        SqlCacheDependency dependency = new SqlCacheDependency(cmd);
        SqlDataReader reader = cmd.ExecuteReader();

        // Add each friend ID to the list
        while (reader.Read()){
            friends.Add(rdr[0]);
        }

        reader.Close();
        dbConnection.Close();

        //insert friends list into cache with associated dependency
        Cache.Insert("friendslist:"+ userid, friends, dependency);
    }
    return friends;
 }

public void AddFriend(int user_id, int new_friends_id){
    // Open the connection
    dbConnection.Open();

    SqlCommand cmd =new SqlCommand("insert into friends_list (owner_id, friend_id) values ("+ user_id +","+ new_friend_id ")";
    cmd.ExecuteNonQuery();

    /* no need to remove from cache because SqlCacheDependency takes care of that automatically */
    // Cache.Remove("friendslist:" + userid);

    dbConnection .Close();
}

Using the SqlCacheDependency class gets around a significant limitation of the ASP.NET Cache class. Specifically, the cache is not distributed. This means that if you have multiple Web front ends, you'd have to write your own code to handle partitioning data and invalidating caches across your various Web server instances. In fact, there are numerous articles showing how to implement such a solution including Synchronizing the ASP.NET Cache across AppDomains and Web Farms by Peter Bromberg and Use Data Caching Techniques to Boost Performance and Ensure Synchronization by David Burgett.

However, let's consider how how SqlCacheDependency is implemented. If you are using SQL Server 7 or SQL Server 2000, then your ASP.NET process polls the database at regular intervals to determine whether the target(s) of the original query have changed. For SQL Server 2005, the database can be configured to send change notifications to the Web servers if the target(s) of the original query change. Either way, the database is doing work to determine if the data has changed. Compared to the memcached this still doesn't seem as efficient as we can get if we want to eke out every last out of performance out of the system although it does lead to simpler code.

If you are a developer on the WISC platform and are concerned about getting the best performance out of your Web site, you should take a look at memcached for Win32. The most highly trafficked site on the WISC platform is probably MySpace and in articles about how they are platform works such as Inside MySpace.com they extol the virtues of moving work out of the database and relying on cache servers.

I was reading reddit this morning and spotted a reference to the Microsoft Popfly team's group picture which pointed out that from reading the job titles in the pic there were 9 managers and 5 developers on the product team. The list of people in the picture and their titles from the picture are excerpted below

From left to right: John Montgomery (Group Program Manager), Andy Sterland (Program Manager), Alpesh Gaglani (Developer), Tim Rice (Developer), Suzanne Hansen (Program Manager), Steven Wilssens (Program Manager), Vinay Deo (Engineering Manager), Michael Leonard (Test Developer), Jianchun Xu (Developer), Dan Fernandez (Product Manager), Adam Nathan (Developer), Wes Hutchins (Program Manager), Aaron Brethorst (Program Manager), Paramesh Vaidyanathan (Product Unit Manager), and Murali Potluri (Developer).

A Microsoft employee followed up the reddit link with a comment pointing out that it is actually 5 dev, 5 PM, 1 test, 3 managers and 1 marketing. This sounds a lot better but I still find it interesting that there is a 1:1 ratio of Program Managers (i.e. design features/APIs, write specs, call meetings) to Developer (i.e. write code, fix bugs, ignore PMs). Although this ratio isn't unusual for Microsoft this has always struck me as rather high. I've always felt that a decent ratio of PMs to developers is more like 1:2 or higher. And I've seen some claim ratios like 1 PM to 5 developers for Agile projects but haven't been able to find much about industry averages online. It seems must discussion about staffing ratios on software projects focus on Developer to Test ratios and even then the conclusion on is it depends. I think the PM to Developer ratio question is more clear cut.

What are good ratios that have worked for you in the past and what would you consider to be a bad ratio?

PS: A note underneath the group picture mentions that some folks on the team aren't pictured but I looked them up and they are in marketing so they aren't relevant to this discussion.

In his post Implementing Silverlight in 21 Days Miguel De Icaza writes

The past 21 days have been some of the most intense hacking days that I have ever had and the same goes for my team that worked 12 to 16 hours per day every single day --including weekends-- to implement Silverlight for Linux in record time. We call this effort Moonlight.

Needless to say, we believe that Silverlight is a fantastic development platform, and its .NET-based version is incredibly interesting and as Linux/Unix users we wanted to both get access to content produced with it and to use Linux as our developer platform for Silverlight-powered web sites.

His post is a great read for anyone who geeks out over phenomenal feats of hackery. Going over the Moonlight Project Page it's interesting to note how useful blog posts from Microsoft employees were in getting Miguel's team to figure out the internal workings of Silverlight.

In addition, it seems Miguel also learned a lot from hanging out with Jason Zander and Scott Guthrie which influenced some of the design of Moonlight. It's good to see Open Source developers working on Linux having such an amicable relationship with Microsoft developers.

Congratulations to Mono team, it looks like we will have Silverlight on Linux after all. Sweet.

I've been thinking a little bit about Google Gears recently and after reading the documentation things I've realized that making a Web-based application that works well offline poses an interesting set of challenges. First of all, let's go over what constitutes the platform that is Google Gears. It consists of three components

• LocalServer: Allows you to cache and serve application resources such as HTML pages, scripts, stylesheets and images from a local web server. 

• Database: A relational database where the application can store data locally. The database supports both full-text and SQL queries.

• WorkerPool: Allows applications to perform I/O expensive tasks in the background and thus not lock up the browser. A necessary evil. 

At first, this seemed like a lot to functionality being offered by Google Gears until I started trying to design how I'd take some of my favorite Web applications offline. Let's start with a straightforward case such as Google Reader. The first thing you have to do is decide what data needs to be stored locally when the user decides to go offline. Well, a desktop RSS reader has all my unread items even when I go offline so a user may expect that if they go offline in Google Reader this means all their unread items are offline. This could potentially be a lot of data to transfer in the split instant between when the user selects "go offline" in the Google Reader interface and she actually loses her 'net connection by closing her laptop. There are ways to work around this such as limiting how many feeds are available offline (e.g. Robert Scoble with a thousand feeds in his subscription list won't get to take all of them offline) or by progressively downloading all the unread content while the user is viewing the content in online mode. Let's ignore that problem for now because it isn't that interesting.

The next problem is to decide which state changes while the app is offline need to be reported back when the user gets back online. These seem to be quite straightforward,

• Feed changed
• Feed added
• Feed deleted
• Feed renamed
• Feed moved
• News item changed
• Item marked read/unread
• Item flagged/starred
• Item tag updated
  

The application code can store these changes as a sequential list of modifications which are then executed whenever the user gets back online. Sounds easy enough. Or is it?

What happens if I'm on my laptop and I go offline in Google Reader and mark a bunch of stuff as read then unsubscribe from a few feeds I no longer find interesting. The next day when I get to work, I go online on my desktop, read some new items and subscribe to some new feeds. Later that day, I go online with my laptop. Now the state on my laptop is inconsistent from that on the Web server. How do we reconcile these differences?

The developers at Google have anticipated these questions and have answered them in Google Gears documentation topic titled Choosing an Offline Application Architecture which states

No matter which connection and modality strategy you use, the data in the local database will get out of sync with the server data. For example, local data and server data get out of sync when:

• The user makes changes while offline
• Data is shared and can be changed by external parties
• Data comes from an external source, such as a feed

Resolving these differences so that the two stores are the same is called "synchronization". There are many approaches to synchronization and none are perfect for all situations. The solution you ultimately choose will likely be highly customized to your particular application.

Below are some general synchronization strategies.

Manual Sync

The simplest solution to synchronization is what we call "manual sync". It's manual because the user decides when to synchronize. It can be implemented simply by uploading all the old local data to the server, and then downloading a fresh copy from the server before going offline.
...

Background Sync

In a "background sync", the application continuously synchronizes the data between the local data store and the server. This can be implemented by pinging the server every once in a while or better yet, letting the server push or stream data to the client (this is called Comet in the Ajax lingo).

I don't consider myself some sort of expert on data synchronization protocols but it seems to me that there is a lot more to figuring out a data synchronization strategy than whether it should be done based on user action or automatically in the background without user intervention. It seems that there would be all sorts of decisions around consistency models and single vs. multi-master designs that developers would have to make as well. And that's just for a fairly straightforward application like Google Reader. Can you imagine what it would be like to use Google Gears to replicate the functionality of Outlook in the offline mode of Gmail or to make Google Docs & Spreadsheets behave properly when presented with conflicting versions of a document or spreadsheet because the user updated it from the Web and in offline mode?  

It seems that without providing data synchronization out of the box, Google Gears leaves the most difficult and cumbersome aspect of building a disconnected Web app up to application developers. This may be OK for Google developers using Google Gears since the average Google coder is a Ph.D but the platform isn't terribly useful to Web application developers who want to use it for anything besides a super-sized HTTP cookie. 

A number of other bloggers such as Roger Jennings and Tim Anderson have also pointed that the lack of data synchronization in Google Gears is a significant oversight. If Google intends for Google Gears to become a platform that will be generally useful to the average Web developer then the company will have to fix this oversight. Otherwise, they haven't done as much for the Web development world as the initial hype led us to believe. 

Duncan Riley over at TechCrunch let's us know Digg API Visualization Contest Delivers Apollo Powered Applications, specifically

The Digg API Visualization Contest held to celebrate the launch of the Digg API is now in its final stages with 10 shortlisted candidates.

Four of the ten finalists are Abode Apollo based applications, remarkable for a platform launched just over 2 months ago.

Agreed, it's pretty remarkable to see so many desktop applications in a Web mashup contest. As John Dowdell warns in his post Apollo ain't casual an Apollo application is a desktop app with all the security implications that come with that. So it is definitely impressive and a little scary to see so many people downloading random executables off of the Web and voting for them in what you'd expect to be a Web-based mashup contest.

It's also somewhat interesting that all the apps seem to be written using some variation of the Flash platform; Apollo, Flex or Flash Lite. I guess it just goes to show that for snazzy data visualization, you really can't beat Flash today. On reading the contest rules it seems it's sponsored by Adobe given that the prizes are primarily Adobe products and submissions are required to be written in Flash. Too bad, it would have been interesting to see some AJAX/DHTML or Silverlight visualizations going up against the Flash apps. 

Pete Lacey has a blog post entitled Rethinking Apollo where he writes

So I dug around in Apollo a little bit, and I did a little bit more thinking about my reflexive dismissal of the technology. And I admit to misunderstanding and miscategorizing Apollo. Here’s what I learned.

Apollo is not a browser plugin, nor does it leverage or extend your browser in any way. It runs completely outside the browser. It is a run-time environment for building cross-platform desktop applications.
...
Lets say you want to build a RSS/Atom reader...But lets add a requirement: my news reader must be cross-platform. That eliminates .NET as a development platform, but still leaves C++. However, with C++ I have to carefully separate my common functionality from my OS-specific functionality and become more of an expert on OS and windowing quirks then I would like, so that’s out. Fortunately, there’s quite a few other ways to go:

1. Browser based
2. Java based
3. Dynamic language based: Perl, Python, Ruby, Tcl
4. Native cross-platform development environment, e.g Qt
5. Apollo
6. Others, e.g. Eclipse RCP

All of these have pros and cons. Browsers are limited in functionality, and quirky. Java is a pain to develop towards-especially GUI apps, has spotty HTML rendering ability, and a non-native look and feel. The dynamic languages are far from guaranteed to be installed on any particular machine—especially Windows machines, and (likely) also have their own look and feel issues. Qt still leaves me in C++ land; that is it’s hard to develop towards. Apollo also has its own look and feel, and will require a download of the runtime environment if it’s not already there (I’m ignoring its alpha release state). I don’t care about any others cross-platform techniques right now.

I think I've found interesting is how a lot of blogosphere pundits have been using Microsoft's Silverlight and Adobe's Apollo in the same sentence as if they are similar products. I guess it's more proof that the popular technology blog pundits don't do much research and in many cases aren't technical enough to do the research anyway.

Although Pete does a good job of explaining the goals of Adobe Apollo with a great example, I think there is a simpler and more cynical way of spelling out the difference between Silverlight and Apollo. I'd describe the projects as 

Apollo is Adobe's Flash based knock off competitor to the .NET Framework while Silverlight is Microsoft's .NET Framework based knock off competitor to the Flash platform.

PS: Shame on Pete for equating dynamic languages with the runtimes for certain popular Open Source dynamic programming languages. The programming language is not the platform and vice versa. After all, both Jython and IronPython are instances of a dynamic programming language that don't have any of the problems he listed as reasons to eliminate a dynamic programming language as a choice for building a cross-platform desktop application. :). 

Have you been trying to distill the recent Microsoft Silverlight announcement into actual concrete bits and pieces? Look no further than this poster which not only lists the various supported browsers and operating systems but also highlights which class libraries from the .NET Framework will make up Silverlight

PS: Found this via Mark Pilgrim's Silly Season post. As usual, excellent and insightful writing by Mark.

Almost six years ago I wrote an article entitled C# from a Java Developer's Perspective which is still one of the most popular comparisons of C# and Java on the Web today. This update to my 2001 article comparing the primary features of C# and Java is a few years later than I planned. Given the amount of requests I've gotten to update it to account for the changes in Java 1.5 and C# 2.0 I'm sure there are many out there who'll find it useful. Below is the table of contents so you can jump to whatever topic interests you.

1. The More Things Change The More They Stay The Same
   This section describes concepts and language features that are almost exactly the same in C# and Java.
   1. We Are All Objects
   2. Keyword Jumble
   3. Of Virtual Machines and Language Runtimes
   4. Heap Based Classes and Garbage Collection
   5. Arrays Can Be Jagged
   6. No Global Methods
   7. Interfaces, Yes. Multiple Inheritance, No.
   8. Strings Are Immutable
   9. Unextendable Classes
   10. Throwing and Catching Exceptions
   11. Member Initialization at Definition and Static Constructors
   12. Boxing
       
       
2. The Same But Different
   This section describes concepts and language features that differ either only in syntax or in some similarly minor manner between C# and Java.
   1. Main Method
   2. Inheritance Syntax
   3. Run Time Type Identification (is operator)
   4. Namespaces
   5. Constructors, Destructors and Finalizers
   6. Synchronizing Methods and Code Blocks
   7. Access Modifiers
   8. Reflection
   9. Declaring Constants
   10. Primitive Types
   11. Array Declarations
   12. Calling Base Class Constructors and Constructor Chaining
   13. Variable Length Parameter Lists
   14. Generics
   15. for-each Loop
   16. Metadata Annotations
   17. Enumerations
       
       
3. An Ever So Slight Feeling of Dèjà Vu
   This section describes concepts and language features that exist in C# that are similar to those that exist in Java but with a significant difference.
   1. Nested classes
   2. Threads and Volatile Members
   3. Operator Overloading
   4. switch Statement
   5. Assemblies
   6. Collections
   7. goto (no longer considered harmful)
   8. Virtual Methods (and final ones too)
   9. File I/O
   10. Object Serialization
   11. Documentation Generation from Source Code Comments
   12. Multiple Classes in a Single File
   13. Importing Libraries
   14. Events
   15. Cross Language Interoperability
       
       
4. Now For Something Completely Different
   This section describes language features and concepts that exist in C# and have no Java counterpart.
   1. Deterministic Object Cleanup
   2. Delegates
   3. Value Types (Structs)
   4. Run Time Type Identification (as operator)
   5. Properties
   6. Multidimensional Arrays
   7. Indexers
   8. Preprocessor Directives
   9. Aliases
   10. Runtime Code Generation
   11. Pointers and Unsafe Code
   12. Pass by Reference
   13. Verbatim Strings
   14. Overflow Detection
   15. Explicit Interface Implementation
   16. Friend Assemblies
   17. The Namespace Qualifier
   18. Iterators (Continuations)
   19. Partial Types
   20. Static Classes
   21. Nullable Types
   22. Anonymous Methods
       
       
5. Wish You Were Here
   This section describes language features and concepts that exist in Java and have no C# counterpart.
   1. Checked Exceptions
   2. Cross Platform Portability (Write Once, Run Anywhere)
   3. Extensions
   4. strictfp
   5. Dynamic Class Loading
   6. Interfaces That Contain Fields
   7. Anonymous Inner Classes
   8. Static Imports
      
6. Conclusion(2001)
7. Conclusion (2007)
8. Resources
9. Acknowledgements

The site formerly known as The Daily WTF has an article entitled Soft Coding which contains the following excerpt

Most programmers consider “Hard Coding” to be a Bad Thing: it’s hack-like, inelegant, and all-around lazy code. And as such, many programmers try their damnedest to avoid it. Unfortunately, this quest of avoidance often leads towards a much worse path: complication, convolution, and all-around unmaintainable code. It’s a path I like to call Soft Coding.

Before I discuss the finer details of Soft Coding, I’d like to briefly define Hard Coding. It’s the practice of embedding “things that shouldn’t be in source code” directly inside of source code. The definition is intentionally vague: while most would agree that database connection strings and logfile directories don’t belong in source code, there’s a lot of gray area. Take, for example, this following code:  

private void attachSupplementalDocuments()

{

if (stateCode == "AZ" || stateCode == "TX") {

//SR008-04X/I are always required in these states

attachDocument("SR008-04X");

attachDocument("SR008-04XI");

}


if (ledgerAmnt >= 500000) {

//Ledger of 500K or more requires AUTHLDG-1A

attachDocument("AUTHLDG-1A");

}


if (coInsuredCount >= 5 && orgStatusCode != "CORP") {

//Non-CORP orgs with 5 or more co-ins require AUTHCNS-1A

attachDocument("AUTHCNS-1A");

}

}

I can already feel some of you cringing: Magic Numbers; String Literals; eww, that’s a lot of Hard Coding! However, not a single character in that example is Hard Coded: there is nothing that “shouldn’t be in source code” in the above code. The function simply implements a very clear and very specific business requirement with very clear and very specific code. Anything less and it would be Soft Coded.

I think it is a laudable goal for The Daily WTF to branch out into describing best practices instead of simply gloating at bad code. I assume this is motivated by some of the comments by Jeff Atwood in his post What's Wrong With The Daily WTF. However the problem I have with this article is that it conflates the difference between hard coding and using magic number (or magic strings).  

From the Wikipedia definition of hard coding:

To hard code or hard coding (also, hard-code/hard-coding, hardcode/hardcoding) refers to the software development practice of embedding output or configuration data directly into the source code of a program or other executable object, or fixed formatting of the data, instead of obtaining that data from external sources or generating data or formatting in the program itself with the given input.
...
EXAMPLE: Fixed installation path
If a Windows program is programmed to assume it is always installed to C:\Program Files\Appname and someone tries to install it to a different drive for space or organization reasons, it may fail to install or run after installation.

EXAMPLE: Startup disk
Some "copy-protected" programs look for a particular file on a floppy disk on startup to verify that they are not pirated. If the computer is updated to a newer machine, which doesn't have a floppy drive, the program now can't be run, since the floppy disk can't be inserted.

From the Wikipedia definition of magic numbers:

The term magic number also refers to the bad programming practice of using numbers directly in source code without explanation. In most cases this makes programs harder to read, understand, and maintain. Although most guides make an exception for the numbers zero and one, it is a good idea to define all other numbers in code as named constants.

This is preferable for several reasons:

• It is easier to read and understand.
• It is easier to alter the value of the number, as it is not redundantly duplicated. Changing the value of a magic number is error-prone, because the same value is often used several times in different places within a program
• It facilitates parameterization.

Hard coding is bad because it assumes that information which should be flexible is actually fixed and unchanging. On the other hand, using magic numbers is a code maintenance problem which does not necessarily mean that the program is inflexible.

Raymond Chen has a blog post entitled You don't know what you do until you know what you don't do where he writes

I've seen a lot of software projects, and one thing I've learned is that you don't have a product until you start saying "No".

In the early phases of product design, you're all giddy with excitement. This new product will be so awesome. It will slice bread. It will solve world hunger. It's designed for everybody, from the technology-averse grandmother who wants to see picture of her grandkids to the IT manager who is in charge of 10,000 computers. It'll run equally well on a handheld device as in a data center.

When I see a product with an all-encompassing description like this, I say to myself, "They have no idea what their product is." You don't know what you do until you know what you don't do. And the sooner you figure out what you don't do the better, because a product that promises to do everything will never ship.

In my five years at Microsoft, I've seen a bunch of projects fail. Some were public flame outs that are still embarrassing to mention today while others are private mistakes that you'll never hear anyone outside the b0rg cube mention. A few months ago I wrote a blog post entitled Top 5 Signs Your Project is Doomed and since then I've considered a few more entries that should be on the list bringing the total to 10. The list below are common signs that a  software project is doomed. Meeting one or two of these criteria isn't necessarily the kiss of death but three or more and you might as well start circulating your resume. 

1. Trying to do too much in the first version. See Raymond's point above.
   

2. Taking a major dependency on unproven technology.
   

3. Competing with an existing internal project that was either a cash cow or had backers that are highly placed in the corporate hierarchy.
   

4. The team is understaffed. If you have less people than can handle the amount of work you have to do then the right thing to do is to scale back the project. Practically every other choice leads to failure.
   

5. Complexity is one of the goals of the project because "complex problems require complex solutions".
   

6. Schedule Chicken
   

7. Scope Creep

8. Second System Syndrome

9. No Entrance Strategy. When a project can't articulate how it goes from a demo or prototype to being in the hands of end users, there's a problem. This is particularly relevant in the "Web 2,0" world where many startups only strategy for success is getting a mention on TechCrunch and the fact that their service has "viral" features.

10. Tackling a problem you don't know how to solve. It's pretty amazing how often I've seen this occur.
    

For the current release of RSS Bandit we decided to forego our homegrown solution for providing search over a user's subscribed feeds and go with Lucene.NET. The search capabilities are pretty cool but the provided APIs leave a lot to be desired. The  only major problem we encountered with Lucene.NET is that concurrency issues are commonplace. We decided to protect against this by having only one thread that modified the Lucene index since a lot of problems seemed to occur when multiple threads were trying to modify the search index.

This is where programming with Lucene.NET turns into a journey into the land of Daily WTF style proportions.

Code Taken from Lucene Examples

public void DeleteDocument(int docNum)

{

lock (directory)

{

AssureOpen();

CreateIndexReader();
indexReader.DeleteDocument(docNum);

}

}

void CreateIndexReader()

{

if (indexReader == null)

{
if (indexWriter != null)

{

indexWriter.Close();

indexWriter = null;

}

indexReader = IndexReader.Open(directory);

}

}


void AddDocument(Document doc)

{

lock (directory)

{

AssureOpen();

CreateIndexWriter();
indexWriter.AddDocument(doc);

}

}


void CreateIndexWriter()

{

if (indexWriter == null)

{
if (indexReader != null)

{

indexReader.Close();

indexReader = null;

}


}

}

As lame as this is, Lucene.NET is probably the best way to add desktop search capabilities to your .NET Framework application. I've heard they've created an IndexModifier class in newer versions of the API so some of this ugliness is hidden from application developers. How anyone thought it was OK to ship with this kind of API ugliness in the first place is beyond me.

I just got a phone call from an RSS Bandit user whose daily workflow had been derailed by a bug in the application. It seems that we were crashing with an ArgumentException stating "Argument already exists in collection" when she tried to import an OPML file. This seemed weird because I always make sure to check if a feed URL exists in the table of currently subscribed URIs before adding it. Looking at the code made me even more confused

            
              

if(!_feedsTable.ContainsKey(f1.link)){

f1.lastretrievedSpecified = true;

f1.lastretrieved = dta[count % dtaCount];
_feedsTable.Add(f1.link, f1); /*
exception thrown here */ 

}
          

So I looked at the implementations of the ContainsKey() and Add() in my data structure which lead me to the conclusion that we need better unit tests

             public virtual bool ContainsKey(String key) { return (IndexOfKey(key)
>= 0); } public virtual void Add(String key, feedsFeed value) { if ((object) key
== null) throw new ArgumentNullException("key"); /* convert the URI to a canonicalized
absolute URI */ try{ Uri uri = new Uri(key); key = uri.AbsoluteUri; value.link = key;
}catch {} int index = IndexOfKey(key); if (index >= 0) throw new ArgumentException(
"Argument already exists in collection.", "key"); Insert(~index, key, value); } 
          

My apologies to any of our users who have been hit by this problem. It'll be fixed in the final release of Jubilee.

I've mentioned in the past that I like the SessionSaver extension for Firefox and would like to implement similar functionality for RSS Bandit. I finished up this feature last night but I kept getting weird behavior. The expected behavior is that when RSS Bandit is launched it remembers the application state from the last time it was closed such as whether it was minimized to the system tray, open browser tabs, what nodes in the feed subscription tree were expanded and what news item(s) were selected. 

The weird behavior was that every once in a while when the application restarted, I'd get an InvalidActiveXStateException which was thrown from the IWebBrowser2.Navigate method when restoring the open browser tabs from the previous time the application ran. Further investigation narrowed the issue down to only showing up when the application had been minimized to the system tray when it was closed and thus being immediately minimized to the system tray when the application was restarted. 

I managed to read a comment on some forum that indicated that the problem is that IWebBrowser2.Navigate method doesn't work if the WebBrowser control isn't visible. This means that this feature won't work as smoothly as I'd like when the application is restarted after being closed from the system tray but it does get rid of the ugly exception.

I hope this blog post explains why the feature will seem wonky in this situation for our users and may prove useful to developers who come across this weird error in the future.

I just found the post Mr. Gosling - why did you make URL equals suck?!? on programming.reddit.com and just had to share

Okay, I’m totally hacked! java.net.URL class officially sucks! The equals method on this shining example of the JDK API mess actually does a blocking DNS lookup on the host string to resolve to an IP address and then compares the IP addresses rather than the host string. What freakin’ sense does that make?

Simple example:

            URL url1 = new URL("http://foo.example.com");

URL url2 = new URL("http://example.com");

          

Let’s say these map to these IP addresses:

            http://foo.example.com => 245.10.10.1

http://example.com => 245.10.10.1

          

Here’s the scary part:

            url1.equals(url2) => true!
            

          

That's definitely the best example of code that deserves to be on The Daily WTF I've seen from a standard library. Just thinking about all the code I have in RSS Bandit that tests URLs for equality, it boggles my mind to think a standard library could have such a craptacular implementation of the equals() method.

Anyone have similar examples from other standard libraries (C++, .NET, JDK, Ruby, etc)? I need some bad code to cheer me up after a day that's already had too many meetings. :)

While browsing my referrer logs I noticed a lot of hits from a comment on Jensen Harris's blog post about the Office 2007 UI being licenced. Below is the comment which has driven several hundred page views on my blog

My reason for moving to a ribbon-like interface for the Phoenix release of RSS Bandit was because I was under the impression that the Ribbon was the wave of the future with regards to application user interfaces in Windows. However I just read a blog post by Mike Torres entitled More on the Office 2007 UI where he points out that practically every Windows application released by Microsoft this year has abandoned the traditional File menu and toolbar structure in a different way. Below are links to the screenshots from Mike's post [and one extra which was suggested by Omar]

1. Office 2007
2. Windows Media Player 11
3. Windows Live Messenger 8
4. Windows Photo Gallery
5. Windows Live Mail _Desktop
   
6. Internet Explorer 7
   

As you can se all of the above applications which where shipped by Microsoft this year embraced the idea of getting rid of the traditional File menu and toolbars yet didn't agree on what to replace them with. As a developer of a Windows application, it is clear to me that the traditional yet consistent File menu and toolbar look is now played out on Windows. The main question is which app I should emulate. If history tells me anything, I can't go wrong betting on Office driving user expectations around what Windows applications should act and feel like. I'm glad to see Infragistics on the list of vendors who will be adopting the Office 2007 UI guidelines. This means we'll likely inherit some best practices around using the Office 2007 Ribbon for free since we now use the Infragistics NetAdvantage GUI components in RSS Bandit.

If this means, I'm going to get people like Mike Dimmick flaming me for not living up to the vision of the 'Ribbon' then so be it. I'd rather that than an application that looked old and busted instead of being the new hotness. ;)