[kafkareceiver] - Add string unmarshaler

[VihasMakwana]

Component(s)

No response

Is your feature request related to a problem? Please describe.

I can't send and receive raw strings.

Describe the solution you'd like

Currently, if I use a console producer and console consumer, kafkareceiver only allows to unmarshal otlp, zipkin or jaeger.
If I'm just sending raw string, the only option I have is to select raw unmarshaler and it will send data in bytes.
It would be great to have a string unmarshaler.

Describe alternatives you've considered

No response

Additional context

No response

[github-actions]

Pinging code owners:

• kafkareceiver: @pavolloffay @MovieStoreGuy

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[github-actions]

Pinging code owners for receiver/kafka: @pavolloffay @MovieStoreGuy. See Adding Labels via Comments if you do not have permissions to add labels yourself.

[MovieStoreGuy]

Could you give more details as to why you believe string should be an encoding type?

I am not exactly sure the difference to raw here.

[VihasMakwana]

Yeah actually.
here's my setup
1). Kafka console consumer
2). [OTEL] Kafka receiver
3). [OTEL] Splunk HEC exporter

I'm sending a string "Event" in kafka consumer and I receive "RXZlbnQ=" in Splunk Dashboard i.e. base64 encoding of "Event".
So, I think we can have a string unmarshaller.
I'm setting encoding as "raw"

[atoulme]

See #20734

[github-actions]

This issue has been inactive for 60 days. It will be closed in 60 days if there is no activity. To ping code owners by adding a component label, see Adding Labels via Comments, or if you are unsure of which component this issue relates to, please ping @open-telemetry/collector-contrib-triagers. If this issue is still relevant, please ping the code owners or leave a comment explaining why it is still relevant. Otherwise, please close it.

Pinging code owners:

• receiver/kafka: @pavolloffay @MovieStoreGuy

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[VihasMakwana]

Closing as it's duplicate