service endpoint APIs

[ssube]

Summary

Individual services may need to expose an endpoint, or a few endpoints, maybe even with their own middleware. These cannot all listen on their own port, and express offers many good ways to delegate a path to a sub-app. Set up some mechanism for services to expose an express app, then expand the express listener to get those services and register their apps.

Scope

• extension service (Endpoint) interface
• express listener
  • endpoints config
    • schema
  • find services and check app

Use Case

Webhook listeners need to accept a request out of their control. Express can handle that, but any sort of clever proxying in the bot will eventually fail. K8s handled this with a similar extension API concept, although it has had a few issues.

Issues

Order of startup will be important. Other services need to have their apps ready (or as a promise?) when the express listener comes calling.