While trying to create a custom HeaderFilterStrategy for camel-kafka I noticed that the two methods of the strategy are used interchanged.
- The KafkaConsumer calls applyFilterToCamelHeaders
- The KafkaProducer calls applyFilterToExternalHeaders
According to the HeaderFilterStrategy Interface, it should be the other way round.
I guess this bug is there since the beginning of the component (therefore affects all released versions).
I have submitted the pull request 3864 to fix this.
As easy as the code is to fix, this is sort of a breaking change for all existing (intentionally wrong) custom HeaderFilterStrategies for camel-kafka.