Create WSGI middleware components with Falcon

[kgriffs]

Jim Baker is working on adding WSGI support to Jython via Fireside and we've talked about making Falcon work well within that context. This got me thinking about more generally supporting the use of Falcon as a lightweight way to write custom middleware that could be used in tandem with Django, etc. apps.

Types of middleware to consider:

• Pre-processing:
  • AuthN/Z - Block unauthorized requests, and inject user info headers (such as a list of roles mapped to that user for RBAC)
  • Rate-limiting - Ensure one user doesn't hog system resources
  • Metering - Collect statistics on usage
  • Routing - Split requests between a legacy app and a new one, allowing for gradual migration from one to the other. Or, to create a facade that combines a collection of APIs into a one.
• Post-processing:
  • Tracing - Inject transaction ID header
  • Support - Send an alert to your operations team on 5xx (or other) errors

[PipocaZalas]

I find very good idea, I recommend a lot to put authentication and authorizers examples, like best practices