Toward a Secret Sky

In his blog, on Friday, August 29, 2008 , Johnathan talked about Google AppEngine , and said the "you can use any web framework you like, as long as it's django" attitude That may have been true then, it probably isn't true now. Glashammer have been working for the last few weeks on getting the Glashammer framework of Werkzeug and Jinja2 running and easy on Appengine. Firstly this wasn't hard. Glashammer is very free about what kind of data storage you use, so using Appengine's DataStore was straightforward. Some utility functions for running easily, add a few decorators for controlling what happens for authentication form redirection to limit views for certain users and we are pretty much done. They have additionally tried to make it easier to install with a little script to get us started. So (since it seems a good start): gh-admin quickstart_gae This will generate a starter AppEngine + Glashammer application that is ready to go. It will al...

Pysqlite doesn't allow you to access the same connection from different threads. The pysqlite manual says: "SQLite connections/cursors can only safely be used in the same thread they were created in." When using Storm (the ORM) with Werkzeug (the WSGI utility lib) we suffer from the problem that the Werkzeug reloader runs code in a thread. Ok this feature is not exactly important in a production environment, but I can't guarantee that whatever platform I will be deploying the application on will not be threaded, so database access should be proofed against this. The solution? The Storm manual mentions that you should use a Store/connection per thread. Someone has already done this with the Middlestorm application, which provides a threadsafe store in the WSGI environ. Rightly or wrongly (since I really don't want to have to wait to have a WSGI environ to get the store instance), and I am not exactly sure this kind of thing should be middleware, but that ...

There are a few ways to run a WSGI application, and today I will comment on the Twisted approach. The magic happens from the twisted.web2.wsgi module, and is fortunately simple. The main advantages I can think of when running with Twisted/Twistd is that: All Python solution (if that really is an advantage) Ability to run other twisted services. Did you want RPC, Email, FTP, remote shell etc for free? Twisted authorization framework Since the application in question has a very simple web part, and is predominately a remote GUI application, this seems the perfect solution. First make a tac file, which you will be running with the old favourite: twistd -ny mytac.tac On to some code: # This is my process for creating my WSGI application. You may have other methods. from graelsite.www.application import make_app from graelsite.www import config wsgi_app = make_app(config) # Now on to the real stuff from twisted.application import service, strports from twisted.web2 import server, channel, w...