Blue/Green Deployments using Versions
I was trying to implement Blue / Green deployments, which APIM doesn't really seem to support out of the box.
What we were planning to do was to (ab)use the versioning to create a "Green" and a "Blue" version of the API. We were going to use revisions to do our actual versioning since our versioning requirements are relatively simple.
I set up the versioning scheme to be Header Based, and I was using a "X-Colour" header to redirect to the correct version. This way, Testing could override the header for canary testing.
My global policy looked something like this:
<set-header name="X-Colour" exists-action=skip>