The problem with using the Channel API this way is not quota usage, it's the rather significant amount of work required on the client & server to make this work.
Making an ajax call from client javascript is trivial. Making an ajax call PLUS setting up, tearing down, and processing messages from the channel API is a massive PITA. A modern development environment shouldn't make you go through this much trouble to do something so simple. Multithreading largely addresses this issue. Async services don't have the issue at all. Jeff On Fri, Jun 17, 2011 at 6:57 AM, Ikai Lan (Google) <ika...@google.com>wrote: > It doesn't hold up the UI but it effectively blocks a connection. With > multithreaded Java this isn't an issue, I suppose - but it will raise your > average user facing latency and your application will not autoscale if it is > frequent. If it is not frequent, the quote usage from the Channel API will > be minimal. > > Ikai Lan > Developer Programs Engineer, Google App Engine > Blog: http://googleappengine.blogspot.com > Twitter: http://twitter.com/app_engine > Reddit: http://www.reddit.com/r/appengine > > > > On Fri, Jun 17, 2011 at 11:56 AM, Luis Montes <monte...@gmail.com> wrote: > >> It's not in a task queue or cron job. It's definitely not holding up the >> UI since the fetch is happening in an AJAX call and the user knows that the >> call will take a few seconds. >> >> Putting it in a task queue means i have to store the results and poll the >> server to check if the results have finished, or use the channel API to push >> a notification back to the client. Those approaches both use more quota >> than would simply allowing for more time on a normal fetch. >> >> Luis >> >> >> >> >> >> On Thu, Jun 16, 2011 at 6:33 PM, Ikai Lan (Google) <ika...@google.com>wrote: >> >>> Are you doing the urlfetch in an offline call (task queue or cron)? If >>> so, the limit should be higher than 10 seconds as of SDK 1.4.1. >>> >>> I hope this isn't an "online" call, because it would suck for a user to >>> wait 30 seconds before a page load. You're better off showing the user a >>> loading screen, handing the job to a task queue, then updating the page when >>> the fetch has finished. >>> >>> Ikai Lan >>> Developer Programs Engineer, Google App Engine >>> Blog: http://googleappengine.blogspot.com >>> Twitter: http://twitter.com/app_engine >>> Reddit: http://www.reddit.com/r/appengine >>> >>> >>> >>> On Fri, Jun 17, 2011 at 7:42 AM, Luis Montes <monte...@gmail.com> wrote: >>> >>>> I understand why there's a 30 second limit for an http connection to >>>> GAE, but I don't understand why server to server URL fetches get timed out >>>> at 10 seconds. >>>> >>>> Seems like as long as you finish up all your processing in less than 30 >>>> you should be fine. How about upping the URL fetch max to 29 seconds? >>>> >>>> >>>> Thanks, >>>> >>>> Luis >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Google App Engine for Java" group. >>>> To post to this group, send email to >>>> google-appengine-java@googlegroups.com. >>>> To unsubscribe from this group, send email to >>>> google-appengine-java+unsubscr...@googlegroups.com. >>>> For more options, visit this group at >>>> http://groups.google.com/group/google-appengine-java?hl=en. >>>> >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "Google App Engine for Java" group. >>> To post to this group, send email to >>> google-appengine-java@googlegroups.com. >>> To unsubscribe from this group, send email to >>> google-appengine-java+unsubscr...@googlegroups.com. >>> For more options, visit this group at >>> http://groups.google.com/group/google-appengine-java?hl=en. >>> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Google App Engine for Java" group. >> To post to this group, send email to >> google-appengine-java@googlegroups.com. >> To unsubscribe from this group, send email to >> google-appengine-java+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/google-appengine-java?hl=en. >> > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine for Java" group. > To post to this group, send email to > google-appengine-java@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
