zuul proxy changes order of query params

[nbyl]

When forwarding requests using the SimpleHostRoutingFilter query parameters are first parsed to a map and afterwards reconstructed when forwarding. This leads sometimes to re-ordering and the query ?edit&p1=v1 may accidentally be changed to ?p1=v1&edit.

This should usually not be a problem, but some legacy applications expect the parameters in the query string to have a certain order. The patches re-uses the original query string when forwarding requests to ensure compatibility with these applications.

[dsyer]

I had to revert this change because it caused some test failures. Can you look into it please?

[nbyl]

sorry for the long reply time. I have looked into the issue and there is a conflict between the "classic" behaviour (parse and filter the query parameters) and the behaviour required in this use case (pass the query string through as it is).

I'm currently working on a proposal, which should be done next week.

[spencergibb]

ping @nbyl

[nbyl]

@spencergibb Sorry for the delay. I have checked the code but the problem is currently not solvable. The parameters are mixed together inside the netflix stack. They are passed back as a map containing no information about the original order. So there is currently no way to solve this in SimpleHostRoutingFilter as I have tried here.

We have solved this using custom zuul filter that bypasses all filtering done insinde the current code and forwards the stuff directly to the target. Are you interested to have this feature in the project?

[jebeaudet]

Related to my last comment here #971, I believe this should be merged (UTs failing are most likely related to query string encoding of #682, but I haven't verified so I might be wrong).

[spencergibb]

Closing

there is currently no way to solve this in SimpleHostRoutingFilter as I have tried here