Adding header to request on IBM API Connect

Question

When receiving a request on API Connect I want to add a header to the subsequent call that it makes to my backend, I've tried using the set-variable policy like so:

execute:
  - set-variable:
      title: SetCustomHeader
      actions:
        - value: xxx
          set: X-HEADER-NAME

And using the Gateway Script:

  - gatewayscript:
      title: gatewayscript
      version: 1.0.0
      source: 'apim.setvariable(''X-HEADER-NAME'', ''xxx'');'

I've tried having the action as either set or add, and I've tried setting the variable name as just the name of the header, and message.headers.X-HEADER-NAME.

According to questions like this one, as well as IBM documentation either one should work, but when logging the request headers on my backend I still don't see the header.

What am I missing?

Answer 1

You need to mention the apim context variables in order to make api connect understand that you want to set the header value. so the value will be :

- gatewayscript:
      title: gatewayscript
      version: 1.0.0
      source: 'apim.setvariable('message.headers.name' ,'value','set');'

Where "name" is the name of the header and "value" is the value of header to be set.

You can find all the api connect context variables here : https://www.ibm.com/docs/en/api-connect/10.0.x?topic=reference-api-connect-context-variables