How do I add fixed prefixes to dynamic topics

[kartikzheng]

The logs collected by fluent-bit are output to Kafka. Can I specify a fixed prefix for topic? For example, I set the dynamic topic as a namespace, and I want to add a fixed prefix to the namespace. What should I do instead? Thank you very much.

`
[OUTPUT]

    Name           kafka

    Match          *

    Brokers        XXXX

    Topics         k8s.namespace

    Topic_key      namespace

    Dynamic_topic  on

    Timestamp_Key  @timestamp

    Retry_Limit    false

`

For example, add the fixed prefix "my"， Assume that namespace is test1, test2, and output topic is my_test1, my_test2.

[YE-Fan]

Expect this feature！

[agup006]

The easiest would be to add a filter right before, a pre-fix might be easy via Lua. A bit more complicated could be using the Nest Lift feature as well https://docs.fluentbit.io/manual/pipeline/filters/nest

[kartikzheng]

thanks. Nest Lift seems to only change the key, not the value