I don't think it's related to transactions. As Ian mentioned above, this behaviour is probably caused by in-memory cashing of the entire datastore by the development server.
This is inconsistent with how the datastore works in production. While there's a chance it won't be fixed, this behaviour at least should be documented, as was the single-process nature of the development web server. Filing an issue will speed this up. On Jan 29, 1:40 pm, 3x3x3 <nerd.l...@gmail.com> wrote: > Thanks for quick reply. > > Before filing an issue, let my problem clear enough. > > Fromhttp://code.google.com/appengine/docs/python/datastore/transactions.html > > > The transaction function may be called multiple times if a datastore > > operation fails due to another user updating entities in the entity > > group at the same time. > > Since dev_appserver serves only one request at a time and > running multiple server instances could not see datastore update each > other. > > Is there any other way to test above scenario on local dev_appserver ? > > On Jan 29, 10:42 am, Alexander Kojevnikov <alexan...@kojevnikov.com> > wrote: > > > Just tried it and indeed a new entity created from the first server's > > admin does not appear in the admin of the second server. However, > > after restarting the second server, the entity is there. Same thing > > when deleting or updating the entities. > > > I suggest that you file an issue and post the link here so that we > > could star it:http://code.google.com/p/googleappengine/issues/list > > > On Jan 29, 12:18 pm, 3x3x3 <nerd.l...@gmail.com> wrote: > > > > Alex, thanks for your help. > > > > I want to make some concurrent requests to test my transaction logic > > > on local dev_appserver.py. > > > > I tried to run two instances of dev_appserver.py with different port: > > > 8080 and 9000. > > > I didn't specify the datastore location path and supposed that both of > > > the two server instances share the same datastore. > > > > I created a entity by using the development > > > consolehttp://localhost:8080/_ah/admin/datastore. > > > But I could NOT see the entity via the second dev_appserver instance > > > consolehttp://localhost:9000/_ah/admin/datastore. > > > > Am I using dev_appserver in a wrong way? > > > > On Jan 28, 9:25 pm, Alexander Kojevnikov <alexan...@kojevnikov.com> > > > wrote: > > > > > Yes, the development server can serve only one request at a > > > > time:http://code.google.com/appengine/docs/python/tools/devserver.html#Usi... > > > > > On Jan 28, 9:03 pm, 3x3x3 <nerd.l...@gmail.com> wrote: > > > > > > I run dev_appserver.py in Windows. > > > > > I add time.sleep(10) in one of my scripts and send request to that > > > > > script in browser. > > > > > During sleep, I send another request to other script in another > > > > > browser window. > > > > > > It's seem that the second request is blocked until the first one has > > > > > done. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appengine@googlegroups.com To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en -~----------~----~----~----~------~----~------~--~---
