Dispatching to more than 20 URLs

[Joshua Fox]

The dispatch.xml file can contain up to 20 routing rules. 

We want to do traffic shaping for A/B testing by directing different subdomains to different services (which are different  variants of the same functionality).

So, we may have a.example.com, b.example.com, c.example.com, and dozens more, some sent to my-service  others to variant-of-my-service.

What is the recommended approach to a more flexible dispatching that exceeds the 20-rule limit? 

Best,

Joshua

[Kenworth (Google Cloud Platform)]

A similar issue was also discussed in part on this thread. Basically developers have two options:

1- File a quota increase request with valid justification to increase the 20-rule hard limit.

2- Have your methods take query parameters and add logic to handle different type of requests in a different way.

[Attila-Mihaly Balazs]

Also, in addition to what Kenworth said, there is the option to do traffic splitting between version: https://cloud.google.com/appengine/docs/standard/python/splitting-traffic

This is not exactly what you're looking for because you're not splitting explicitly based on a domain name but rather Google does the splitting based on IP/cookies (depending on how you set it up), but it could be worth taking a look at.

Cheers,
Attila