The Wolverine release of RSS Bandit has entered its final stretch; the bug count is under 15 from a high of over 50, the codebase is frozen except for critical fixes, and translations have started to trickle in. It is looking like the final version number for Wolverine will be v1.3.0.25 but don't quote me on that just yet.

Torsten and I have started talking about what we'd like to see in the following release, currently codenamed Nightcrawler. Over the next few weeks I'll be sharing some of our thoughts on where we'd like to see RSS Bandit go and eliciting feedback from our users. The first topic I have in mind is building a richer extensibility model. Torsten and Phil have discussed this issue in their blogs in the posts Fighting Ads and  Building a Better Extensibility Model For RSS Bandit respectively. As Phil wrote

Currently, the only plug-in model supported by RSS Bandit is the IBlogExtension interface. This is a very limited interface that allows developers to write a plug-in that adds a menu option to allow the user to manipulate a single feed item.

The ability to interact with the application from such a plug-in is very limited as the interface doesn't define an interface to the application other than a handle. (For info on how to write an IBlogExtension plug-in, see this article.)

Despite the limitations of IBlogExtension, it has led to some interesting plugins such as my plugin for posting links to from RSS Bandit.  This was actually a feature request which I fulfilled without the user having to wait for the next version of RSS Bandit. I'd like to be able to fulfill more complex feature requests without having users wait for the next version. Given the small number of IBlogExtension plugins I've seen come from our user base I'm pretty sure that it is quite likely that a richer plugin model would just end up mostly being used by Phil, Torsten and myself.  However I'd still like to get some feedback from our users about where they'd like to see more extensibility. Below are some of the extensibility points we've discussed along with usage scenarios and possible risks. I'd like to know which ones our users are interested in and would consider writing plugins with.

Feed Preprocessing

Plugins will be able to process RSS items just after they have been downloaded but before they are stored in RSS Bandit's in-memory and on-disk caches. This is basically what Torsten describes in his post Fighting Ads.

Use Case/Scenario: A user can write a plugin that assigns scores to news items according to the user's interests (e.g. a Bayesian filter) then annotates each news item with its score. For example, for me posts containing 'XML' or 'MSN Spaces' would be assigned a score of 5 while every other post could be assigned a score of 3. Then I could create a newspaper style that either grouped posts by their ranking or even filtered out posts that didn't have a certain score.

Another potential use case is pre-processing each news item to filter out ads as Torsten did in his example.  

Risks: My main concern with this approach is that badly written plugins could harm cause problems with the normal functioning of RSS Bandit. For example, if a plugin got stuck in an infinite loop it could hang the entire application since we'd never get back news items from the pre-processing step. Given that this is an instance of the halting problem I know we can't solve it in a general way so I may just have to acept the risks.

Pluggable protocols

Every once in a while, users ask for RSS Bandit to support other data formats and protocols than just RSS & Atom over HTTP. For example, I'd like us to support USENET newsgroups while I've seen a couple of requests that we should be able to support subscribing to POP3 mail boxes.

Ideally here we'd have a plugn infrastructure that allowed one to plugin both the parser and the protocol handler for a given format. The plugin would also specify the URI scheme used by the newly supported format so that RSS Bandit would know to dispatch requests using that plugin

Use Case/Scenario: In the case of USENET support the user would provide a plugin that knew how to parse messages in the RFC 822 format and how to fetch messages using NNTP. The USENET plugin would also register itself as the handler for the nntp and news URI schemes. The user could then subscribe to newsgroups by specifying a URL such as news:// in the new feed dialog.  

Risks: Same as with Feed Preprocessing.

Hosted Winforms Applications

A user could add a .NET Winforms application  to RSS Bandit. This application would appear as a tab within the main Window and all its functionality could be used from RSS Bandit. There would also be some hooks for the application to register itself within the RSS Bandit main menu as well as mechanisms to pass information back and forth between the hosted application and RSS Bandit.

Use Case/Scenario: One would be able to host blog posting clients such as IMHO in RSS Bandit. The blog client would be distributed and updated independently of RSS Bandit.

Risks: This would be a great deal of work for questionable pay off.

Pluggable Storage

RSS Bandit currently caches feeds as RSS files on disk, specifically at the location C:\Documents and Settings\[username]\Application Data\RssBandit\Cache. It should be possible to specify other data storage sources and formats such as a relational database or Atom feeds.

Use Case/Scenario: A user can write a plugin that stores all RSS Bandit's feeds in a local Access database so that data mining can be done on the data.

Another use case is writing them to disk but in a different format than RSS. For example, one could write them to disk using the format used by another application so that the user could use both applications but have them share a single feed cache.

Risks: The same as with Feed Preprocessing.