Hi Phil, It looks like App Engine is neglecting to start up a new instance of your app just to serve your self-request, and there are no spare instances already running.
Why are you URLFetching yourself, though? I'm no Java expert, but I'm fairly certain there are accepted ways to run a servlet yourself, without having to make an HTTP request. -Nick Johnson On Mon, Jun 21, 2010 at 7:01 PM, PhilBeaudoin <[email protected]>wrote: > I need to use the URL Fetch API to load dynamic content (a JSP or > servlet-generated content) from the same application that uses URL > Fetch. It looks like this is not allowed on AppEngine -- and it > doesn't seem related to the documented limitation that URL Fetch > cannot get its own URL. (The URL is different, even though is has the > same domain). Another point to note is that this works if I'm using > URL Fetch to get static content (an HTML page). > > * Background * > > I need to do this to serve content generated with HTMLUnit to make my > app crawlable by search engines, as described in: > http://code.google.com/web/ajaxcrawling/ > > * AppEngine log analysis * > > From my browser I request > http://puzzlebazaar.appspot.com?_escaped_fragment_=main > > From the AppEngine log I see that the request for > http://puzzlebazaar.appspot.com?_escaped_fragment_=main starts, it > goes through HTMLUnit which then uses URL Fetch to get > http://puzzlebazaar.appspot.com#!main. Following this I get an > IOException : > com.philbeaudoin.gwtp.crawler.server.CrawlFilter logStackTrace: > java.util.concurrent.ExecutionException: java.io.IOException: Timeout > while fetching: > http://puzzlebazaar.appspot.com#!main > > The page content is empty. This exception is caught, the servlet > continues and terminates normally. > > Then the request for http://puzzlebazaar.appspot.com#!main starts. > From the timings in the AppEngine logs it's clear that this request > starts too late, that is, after the original request has terminated. > > * What I tried * > > 1) To make sure it wasn't a problem with HTMLUnit, I used URL Fetch > directly, but got the same behavior. > 3) I tried fetching dynamic content from the same domain but with more > differences in the URL. (Not just the parameters.) It fails. > 2) I tried fetching a statically-served HTML page from the same > domain. This works. > > * Questions * > > 1) Is this documented behavior from AppEngine? > 2) Is there a way to work around this? > 3) Are there any plans to allow this in the future? > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]<google-appengine%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine?hl=en. > > -- Nick Johnson, Developer Programs Engineer, App Engine Google Ireland Ltd. :: Registered in Dublin, Ireland, Registration Number: 368047 Google Ireland Ltd. :: Registered in Dublin, Ireland, Registration Number: 368047 -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
