[WIP] generate python, go, javascript, java clients from openapi spec

[houqp]

relates to #9080, based of work from https://github.com/mik-laj/airflow-api-clients.

TODO:

• fix connexion integration
• fix python tests
• run update-client.sh to test api spec change in CI

Open questions:

• Do we want to also implement artifact publish for python, javascript and java?

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[houqp]

@mik-laj I am thinking of pulling this openapi spec change into a separate PR so we can get it merged in early to avoid conflicts. what do you think?

[mik-laj]

Good idea. This will reduce the number of conflicts.

[houqp]

alright, sent #9495.

[mik-laj]

Can you split these changes into several PRs? Each language has different requirements that we will have to consider to generate the perfect client library.
Here is an example of operations that are done by the Kubernetes team.
https://github.com/kubernetes-client/gen/blob/master/openapi/preprocess_spec.py
I will also have to involve other reviewers who have better language. It will be easier if each language will be in a separate PR.

Do we want to also implement artifact publish for python, javascript and java?

We can use Github Action to store development artifacts.

[houqp]

will replace this PR with change for one language at a time starting with Go.