JSON formatted responses

Problem/Motivation

JSON responses to ticket and proxy validation requests can be return in JSON and XML. The JSON format currently is not actioned.

The issue #2886282: Add RPC endpoints for headless authentication → is also related as it adds a headless login which uses json to communicate. @todo Determine if this is in the CAS protocol.

Steps to reproduce

Try to use JSON for requests and you will be given an XML response.

Proposed resolution

Implement JSON responses where appropriate.

Remaining tasks

• ✅ File an issue
• ➖ Addition/Change/Update/Fix
• ➖ Testing to ensure no regression
• ➖ Automated unit testing coverage
• ➖ Automated functional testing coverage
• ➖ Security
• ➖ Documentation
• ➖ Code review by maintainers
• ➖ Full testing and approval
• ➖ Credit contributors
• ➖ Review with the product owner
• ➖ Release notes snippet
• ❌ Release

User interface changes

• N/A

API changes

• Proxy and Ticket validation requests can now specific json format and get a response.

Data model changes

• N/A

Release notes snippet

• @todo Link to issue