Really struggling to get resolution on this issue and it would appear to be on google's end.
My app is a few years old and am trying to add capability to upload files to the blobstore. Works fine locally and works fine in a new project. I would prefer not to have to migrate to a new project but it's looking like my only option at this point. Also am unable to use mysql v2 (v1 works) which further leads me to believe that this is a config issue on google's end.
Anyway, standard upload to default bucket and I get a 503. Have read all other posts and tried mucking around with service accounts, etc. to no avail. 503 means no log entries so there's really no way for me to debug.
Would be cool if google would lend a bit of support here and save me from some pain. Long time user.