How to set up a staging environment on Google App Engine

[systempuntoout via StackOverflow]

Having properly configured a Development server and a Production server, I would like to set up a Staging environment on Google App Engine useful to test new developed versions live before deploying them to production.

I know two different approaches:

A. The first option is by modifying the app.yaml version parameter.

version: app-staging

What I don't like of this approach is that Production data is polluted with my staging tests because (correct me if I'm wrong):

1. Staging version and Production version share the same Datastore
2. Staging version and Production version share the same logs

_{Regarding the first point, I don't know if it could be "fixed" using the new namespaces python API.}

B. The second option is by modifying the app.yaml application parameter

application: foonamestaging

with this approach, I would create a second application totally independent from the Production version.
The only drawback I see is that I'm forced to configure a second application (administrators set up).
With a backup\restore tool like Gaebar this solution works well too.

What kind of approach are you using to set up a staging environment for your web application?
Also, do you have any automated script to change the yaml before deploying?

Please DO NOT REPLY directly to this email but go to StackOverflow:
http://stackoverflow.com/questions/3793860/how-to-set-up-a-staging-environment-on-google-app-engine

[Rad Apdal via StackOverflow]

Currently using Option B. Setting up new namespace on a currently running application you will run into problems:

1. How do I migrate data from my production to my new namespace?
2. Since keys are bound per namespace, how do I keep properties from referring to other entity keys correctly when data is migrated?

Please DO NOT REPLY directly to this email but go to StackOverflow:

http://stackoverflow.com/questions/3793860/how-to-set-up-a-staging-environment-on-google-app-engine/44016966#44016966