Pass metadata to Kalix service from Play

[glop.postbox.0u]

Hello!

I’m not able to send custom metadata from Play (using play-grpc) to a Kalix service.

    singleResponseRequestBuilder
      .addHeader("Authorization", "BAR")
      .addHeader("X-Request-Id", "1234")
      .invoke(request)

Only the Authorization header is passed. The X-Request-Id is not. Is this expected behavior? If yes, is it because such values are expected to be passed as claims?

Thanks.

[efgpinto]

Hi,

You’re right, only “Authorization” is passed by default. Otherwise, you need to specifically add the header to an allow list. See the original message from Johan for an example:

How to access request client ip?

I see we are missing docs for this. The client IP header needs an opt in to be available (as it has a slight performance overhead for each request). For the JVM SDK that is done by adding x-forwarded-for to the forwardedHeaders for the component(s) where you need it. The API for doing that is a bit cumbersome though, you will need to drop down to calling Kalix#register yourself instead of using the generated KalixFactory, something like this (in Scala, Java should look roughly but not exactly …

(Something we need to add to our docs I reckon.)

[glop.postbox.0u]

Ah, interesting. Thanks @efgpinto