DataPower firmware version 6.0 changes Content-Length header to chunked
I upgraded DataPower from V5 to V6. Now, when my client application submits HTTP/1.1 requests via DataPower, the responses returned to the client no longer include the Content-Length header. What changed between the versions?
A client that is fully compliant to the HTTP/1.1 specification must be able to handle the Transfer-Encoding header.
Up to 5.0.0 firmware, when HTTP/1.1 is used on the front end, DataPower selected the response length encoding (Chunked or Content-Length) using rather complex criteria that were not always optimal, specifically preventing streaming in some cases.
To resolve the above defect, starting with 6.0.0, DataPower always uses Transfer-Encoding (chunked) instead of Content-Length header when responding to HTTP/1.1 request.
This is compliant with IETF RFC 7230 section 4.1 about Chunked Transfer Coding that has the following statement:
"A recipient MUST be able to parse and decode the chunked transfer coding."
All DataPower firmware releases generate responses with Content-Length format when using HTTP/1.0 protocol.