KC: Add options to change log levels for Kafka Connect

[yeikel]

Issue submitter TODO list

• I've searched for an already existing issues here
• I'm running a supported version of the application which is listed here and the feature is not present there

Is your proposal related to a problem?

It is often necessary to change the log levels of Kafka connect at runtime during development and debugging. Currently, I need to multi task between the UI and the Kafka Connect REST API as this feature is not exposed in the UI

Describe the feature you're interested in

Expose UI elements to access the different endpoints that the API exposes that can be used to adjust the log levels.

Example features include :

• Check log levels
• Get the log level for a specific logger and/or connector
• Change the log level for a specific logger and/or connector

Describe alternatives you've considered

The only option I am aware of is to call {connect}/admin/loggers/{logger name} manually

Version you're running

c8a8759

Additional context

From provectus/kafka-ui#4349

See https://cwiki.apache.org/confluence/display/KAFKA/KIP-495:+Dynamically+Adjust+Log+Levels+in+Connect

[Haarolean]

Looks useful, we'd need an UI solution first I guess

[yeikel]

Looks useful, we'd need an UI solution first I guess

How do we go about that? From what I understand, there are design documents to update

Currently, what I envision is the following:

• In the Kafka Connect Home Page(where we list all the connectors) have a link to "Logging Configuration"
• Upon opening the page, display a table such as

This table is the result of calling /admin/loggers

logger name	LEVEL
io.confluent.connect.s3	DEBUG
root	INFO

Save

The Save button should do the following for each entry of the table:

curl -s -X PUT -H "Content-Type:application/json" /admin/loggers/logger name -d '{"level": "LEVEL"}'

This table should :

1. Allow new entries (perhaps a + button). Removing should not be possible because an explicit log level is expected
2. The level should be a drop down(nice to have) or a free text

Because logger name is hierarchical , the response should show the RAW message from the endpoint as more than one class can be impacted. For example, changing io.confluent.connect, will also impact io.confluent.connect.s3

A table is not necessarily needed but maybe a good to have.

We can also show the raw response from the endpoints using a similar view to the connector config