[Serve] Ray Dashboard reports HTTP 204 under Error QPS

[chasleslr]

What happened + What you expected to happen

When a deployment returns an HTTP 204, it is reported as an error in the Ray Dashboard. Specifically, these queries are reported under the "Error QPS" charts. An HTTP 2xx should not be considered as an error.

Versions / Dependencies

macOS 14.3
Python: 3.12
ray[serve] 2.37.0

Reproduction script

from ray import serve
from fastapi import FastAPI, Response


app = FastAPI()


@serve.deployment
@serve.ingress(app)
class Deployment:
    @app.post("/")
    def post(self, text: str) -> str:
        return Response(status_code=204)


deployment_app = Deployment.bind()

Issue Severity

None

[Superskyyy]

I will fix that, current check is only checked against status code 200

                            is_error=status_code != "200",

[Superskyyy]

Shall we consider whatever doesn't start with 2xx an error? I guess its more of a business-oriented decision but this sounds a general approach that fit most. wdyt @edoakes

[Superskyyy]

Fix added

[edoakes]

@Superskyyy yes I think characterizing 2XX as success sounds good to me, let me review the PR