Reporting/overview system for collection/process metadata merging issues

[soxofaan]

follow up of #4 (merging of process metadata) and #5 (merging of collection metadata):

It turns out that there can be quite some issues when merging metadata, of varying degrees of importance/impact. It would be good if we have some kind of system to get an overview or report issues

[soxofaan]

still needs a bit of brainstorm to make more concrete, but some things to consider:

• allow this to run as kind of integration tests (e.g. critical merge issues have to be resolved before deploying)
• allow to run continuously as cron and report (e.g. daily health check)
• allow other parties/back-ends to run this against a dev build for example
• keep it simple as cli tool (which reporting format then?), or make it a web view (with auth?)

[soxofaan]

77 has been merged now

[soxofaan]

With #77 being merged the big chunk of work is done. Some additional minor follow-up TODOs:

• process metadata merging:
  • [x] merge "deprecated"
  • [x] merge "experimental"
  • [x] merge "examples"
  • [x] merge "links"
  • [x] ignore "description" when comparing "returns" field
  • [x] report missing parameter "description" (which is required) instead of falling back on "name"
• collection metadata merging: check TODO comments in code
• general
  • [x] MarkDownReporter: drop distinction between warning/critical, or handle it more generically
  • [x] define common interface for reporter classes (instead of disconnected MarkDownReporter and LoggerReporter
  • [x] validator.py: add cli option to select check for collections only, processes only or both

[soxofaan]

some more follow up issues:

• [ ] https://github.com/Open-EO/openeo-aggregator/issues/80
• [ ] https://github.com/Open-EO/openeo-aggregator/issues/81

[soxofaan]

most follow up TODO's are done or moved to separate tickets. I think we can close this #76 now.

thanks!