Enable enhanced support for partitioned services

[lawrencegripper]

Currently Traefik for SF only has basic partitioning support.

Evaluate using Frontends or a new middleware to route requests to the correct partition.

Proposals

Frontends

Traefik supports routing rules per frontend. For each partition in a service we could create a frontend with a rule which matches requests for that parition.

To setup this behavior a label could be set traefik.paritioning and it's value would be a CSV separated lists of the matchers for each of the partitions.

For example: traefik.partitioning = paritionid1:/articles/{category}/{id:[0-3]+}, paritionid2:/articles/{category}/{id:[0-3]+}

Questions:

• Does Traefik scale well with a large number of frontends?
• Do matchers offer the flexibility needed?

Middleware

TBD

[jjcollinge]

now tracked in #45