api: move default response from XML to JSON

[marcaurele]

Description

Moving the default response type (when not provided) from XML to JSON.

Java community used to love XML a lot, but let's face it, nowadays people are using JSON whenever they can.

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)
• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Enhancement (improves an existing feature and functionality)
• Cleanup (Code refactoring and cleanup, that may add test cases)

How Has This Been Tested?

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly. (default response is now JSON cloudstack-docs#25)
  Testing
• I have added tests to cover my changes.
• All relevant new and existing integration tests have passed.
• A full integration testsuite with all test that can run on my environment has passed.

[rafaelweingartner]

This can break compatibility with tools that assume the default return as XML. Should'nt we discuss it first in the users and dev lists?

[yadvr]

I think we should keep this, otherwise people won't be able to get XML output if a response type was provided.

[marcaurele]

It's some dummy code. The content type is set when writing the String response to the HttpResponse later on. Doing it so early does not have much sense. See HttpUtils.writeHttpResponse()

[wido]

I agree with @rafaelweingartner

This would be a rather big change and I think we should discuss it properly. I understand the change, but we will break a lot of things.

Do I hear somebody saying CloudStack 5.0?

[DaanHoogland]

let's do the 5.0 dance

[rafaelweingartner]

As we discussed in CCC Montreal, this would fit our requirements for breaking changes.

[yadvr]

It will be nearly 3+ years old PR and can't be accepted which would break our default API response compatibility. Pl re-open this PR if this can be reworked again latest main. Thank you for the PR.