Google App Engine and 404 error

Question

I've setup a static website on GAE using hints found elsewhere, but can't figure out how to return a 404 error. My app.yaml file looks like

- url: (.*)/   static_files: static\1/index.html   upload: static/index.html  - url: /   static_dir: static 

with all the static html/jpg files stored under the static directory. The above works for files that exist, but returns a null length file if they don't. The answer is probably to write a python script to return a 404 error, but how do you set things up to serve the static files that exist but run the script for files that don't?

Here is the log from fetching a non-existent file (nosuch.html) on the development application server:

ERROR    2008-11-25 20:08:34,084 dev_appserver.py] Error encountered reading file "/usr/home/ctuffli/www/tufflinet/static/nosuch.html": [Errno 2] No such file or directory: '/usr/home/ctuffli/www/tufflinet/static/nosuch.html' INFO     2008-11-25 20:08:34,088 dev_appserver.py] "GET /nosuch.html HTTP/1.1" 404 - 

Answer 1

You need to register a catch-all script handler. Append this at the end of your app.yaml:

- url: /.*   script: main.py 

In main.py you will need to put this code:

from google.appengine.ext import webapp from google.appengine.ext.webapp.util import run_wsgi_app  class NotFoundPageHandler(webapp.RequestHandler):     def get(self):         self.error(404)         self.response.out.write('<Your 404 error html page>')  application = webapp.WSGIApplication([('/.*', NotFoundPageHandler)],                                      debug=True)  def main():     run_wsgi_app(application)  if __name__ == "__main__":     main() 

Replace <Your 404 error html page> with something meaningful. Or better use a template, you can read how to do that here.

Please let me know if you have problems setting this up.

Answer 2

google app engine now has Custom Error Responses

so you can now add an error_handlers section to your app.yaml, as in this example:

error_handlers:  - file: default_error.html  - error_code: over_quota     file: over_quota.html