Cid Dennis

Singleton Jobs in Delayed Job

So I am working on a project where I want a job to run only if there is not one running with the same worker class.   So I monkey patch the Delayed::Job class to have a new method called job_exist?(job).

 

 

Delayed::Job.class_eval do  

    def self.job_exist?(job)    

            return Delayed::Job.find(:first, :conditions => ["handler like ?", "%" + job.name + "%"])  

    end

end

 

Now I can do code that looks like this 

Delayed::Job.enqueue LoadImages.new if !Delayed::Job.job_exist?(LoadImages)

 

I know this is not perfect but for jobs that are considered singletons it works well. 

 

 

Firefox 4 Jetpack Autoupdate

So I am working on a new FireFox4 extension using the new JetPack SDK and had a hard time finding the docs to use the browsers auto update feature.    After a number of google search I finally found this link https://jetpack.mozillalabs.com/sdk/1.0b4/docs/dev-guide/addon-development/cfx-tool.html.   

 

Here is what it says hope this helps other find out how to do this faster.

 

updateURL and updateLink

If you choose to host the XPI yourself you should enable the host application to find new versions of your add-on.

To do this, include a URL in the XPI called the updateURL: the host application will go here to get information about updates. At the updateURL you host a file in the update RDF format: among other things, this includes another URL calledupdateLink which points to the updated XPI itself.

The --update-link and --update-url options simplify this process. Both options take a URL as an argument.

The --update-link option builds an update RDF alongside the XPI, and embeds the supplied URL in the update RDF as the value of updateLink.

The --update-url option embeds the supplied URL in the XPI file, as the value of updateURL.

So if we run the following command:

  cfx xpi --update-link http://example.com/addon/latest
          --update-url http://example.com/addon/update_rdf

cfx will create two files:

• an XPI file which embeds http://example.com/addon/update_rdf as the value of updateURL
• an RDF file which embeds http://example.com/addon/latest as the value of updateLink.