Introduction
Recently I encountered a basic router scenario. However the information I could use as a condition was not included in the message itself. I had to pass it to CPI, but didn’t want to enrich the message and mess it up. I figured out that custom header would be the great solution, however as it occurred, it wasn’t so easy (now it is of course).
Steps
So you would like to pass a custom header to CPI.
SoapUI
In SoapUI you would pass it on like this:
ABAP
In ABAP it is possible thanks to the best library cl_http_client:
lo_httpclient->request->set_header_field(
name = ‘CustomHeader‘
value = ‘100‘ ).
SAP CPI
This is the most important step – you need to enable custom headers so CPI can accept them. Just go to your iFlow, click on the white space behind the flow and you will be displayed a “Integration Flow” menu. Go to “Runtime Configuration” and fill “Allowed Header(s)”.
You could also type *. In this case CPI would accept all incoming headers.
Read your header
Now your custom header will be visible in CPI. In order to read the value use the expression
${header.CustomHeader}. Of course you could get access to any header using such expression. In my case I would use it in router step.
Summary
I think it is a smarter and safer way to control your message flow. Instead of messing with payload you “hide” your controls in different part of message exchange. What do you think?
