Support for retries

[itsmurugappan]

Issue: Incase the openfaas gateway is down or function does not scale in time from 0 to 1. The messages might be lost.

Proposal: While calling the gateway is it a good idea to add retries and on multiple failures add the message back to the queue.

[alexellis]

Hi thanks for the suggestion.

I'm happy to explore this idea. There are a number of ways it can be achieved:

• at the publisher/client
• in the individual connector implementation
• in this SDK generically
• in the gateway
• through use of a service mesh or proxy (envoy for instance can be set to automatically retry)

[itsmurugappan]

Thank you Alex.

• In this sdk, retries can be added for function calls for non 200 responses.
• In the connector implementation, failure message can be added back to the queue.