Nostpy relay now has websocket rate limiting, bug fixes and new metrics \ stacker news ~nostr

Now you can rate limit websocket clients with a token based system to pump the brakes on clients that are asking too much of your relay

Enhancements

Add token based websocket rate limiter to websocket handler
- Closes websocket connection and sends client "OK" rate limit message
  - Limits by client IP address
  - Sends gauge metric with client tag to StatsD server to keep track of rate limited clients
- After some time passes, token bucket is refilled and client can make requests again provided they stay under their rate limit
Reply to client with "NOTICE" message when subscription closes
- Also sends "OK" true message to client when event successfully added
Many organizational improvements in websocket handler
- New ExtractedResponse and WebsocketMessages help organize and make for more readable code
  - Parse and format messages outside of the handler functions

Bug Fixes

Fixed duplicate EOSE message returned to client from websocket subscription handler
Fixed redis cached result parsing bug that was returning a single ] as content for a REQ message when redis cache returned b"[]"
- Try/except block for parsing, does not send redis results less than 2 charecters back to websocket handler, instead sends EOSE