BE: Metrics: Response payload should end with an EOF

[AleCostaSF]

Issue submitter TODO list

• I've looked up my issue in FAQ
• I've searched for an already existing issues here
• I've tried running main-labeled docker image and the issue still persists there
• I'm running a supported version of the application which is listed here

Describe the bug (actual behavior)

I am using Alloy to scrape metrics from the /metrics endpoint, but I keep getting this error:

data does not end with # EOF

I checked and the textfile returned from the endpoint is missing the final # EOF line, which is mandatory as far as I understood.

I have the same issue with Prometheus directly.

Expected behavior

The content returned by /metrics should end with # EOF

Your installation details

A Kubernetes deployment running ghcr.io/kafbat/kafka-ui:v1.4.2

Steps to reproduce

1. Launch the Kafka UI
2. Call the /metrics endpoint
3. Check that the content is missing the final # EOF line

Screenshots

No response

Logs

No response

Additional context

To make sure this is the issue, I wrote a small proxy script running as sidecar that appends that line and everything works.

[github-actions]

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[chris-potato]

Hi,

I'm getting exactly the same issue when trying to scrape this /metrics endpoint.

Not sure if it's useful, but from a working scraper, I get: content-type: text/plain;version=0.0.4;charset=utf-8 returned. But from my Kafbat scraper, I get content-type: application/openmetrics-text; version=1.0.0; charset=utf-8 returned.

This also means that the Swagger docs are misaligned, as they mention the returned content-type being application/text, which I was expecting to be returned.

• kafka-ui/contract/src/main/resources/swagger/kafbat-ui-api.yaml

  Line 214 in c30851c

  application/text:

• kafka-ui/contract/src/main/resources/swagger/kafbat-ui-api.yaml

  Line 234 in c30851c

  application/text: