Mongrel. Serving, Deploying, and Extending Your Ruby Applications

6.6. Handlers as GemPlugins

Handlers can also be GemPlugins, and they are the preferred way to distribute your handlers. If we take our UserAgentRemover handler and turn it into a GemPlugin, the code would be:

class UserAgentRemover < GemPlugin::Plugin "/handlers" include Mongrel::HttpHandlerPlugin def process(req, resp) if req.params.delete "HTTP_USER_AGENT" STDERR.puts "Removed a user agent" end end end uri "/dumped", :handler => plugin("/handlers/useragentremover")

The only change made to the code was to do the usual GemPlugin::Plugin voodoo, include the HttpHandlerPlugin module, and then use the Configurator#plugin function to set the :handler => plugin() setting.

6.6.1. More Examples

The Mongrel RubyForge project Files section has several other examples of using the GemPlugin system to create distributions of your handlers and commands. You should take a look at mongrel_upload_progress as a full example of implementing a useful set of handlers as GemPlugins.