22 karma · joined October 9, 2015
What was the specific Python 3 issue? I didn't see anything in your post specifically about Python 3.
(I work on the Python developer experience for Google Cloud Platform)
You can host your own Postgres on Compute Engine [1] or use a hosted provider like ElephantSQL [2]. You can use whatever client library you want to connect to postgres in App Engine flexible.
Same story for redis - you can host it on Compute Engine [3] or use something like redislabs.
[1] https://cloud.google.com/solutions/set-up-postgres
[2] https://www.elephantsql.com/
[3] https://cloud.google.com/launcher/?q=redis
Note: I'm in Developer Relations for Google Cloud Platform
> Google App Engine's dev_appserver.py completely broke after an update, caused in part by another Google library being installed (protobuf...). Still not sure if the fix was rolled into a release yet...
We've been having a lot of fun with how tricky namespace packages are in Python. We've got a fix in for this issue that should hopefully be in the next SDK release, and we're looking into ways to better isolate dev_appserver from the OS environment.
A simple workaround is to activate an empty virtualenv before running dev_appserver.
Please keep in mind that Managed VMs is still in beta, however, there are other parts of Google Cloud Platform that are in GA, including Compute Engine (IaaS), and Container Engine (somewhere between PaaS and IaaS). In fact, depending on how much control you want, Container Engine can be a better fit than App Engine.
(disclaimer: I work for Google on Cloud Platform, but not on anything Java related)
I've seen many Python apps that connect to a free MongoDB instance hosted on Mongolab.
(also worth noting that Node.js support for App Engine is currently in beta.)
(disclaimer: I work for Google on Cloud Platform)