Resolve "Authentication for Meltano Analyze" - [merged]

[MeltyBot]

Merges 1-authentication-for-meltano-analyze -> master

Migrated from GitLab: https://gitlab.com/meltano/meltano/-/merge_requests/341

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Merge Request Checklist

• Link to an issue
• Include the proposed fix or feature
• Include and update tests for the modified code
• Include a documentation change
• Add a CHANGELOG.md entry in the Unreleased section

Once your merge request is complete, please assign it a Meltano maintainer for review cycle. Once the review cycle finished, the reviewer shall approve the merge request so it can be merged by any Meltano maintainer.

Closes #1

This MR adds authentication to the Meltano UI using flask-security and flask-authlib.

To enable authentication, you must run meltano ui using the FLASK_ENV=production.
When run in development, authentication will be disabled.

If you want to enable OAuth2 (OpenID Connect) on GitLab.com, you can set the following environment variables in your .env.

Note: the real values can be found in the Meltano 1Password Vault.

.env

OAUTH_GITLAB_APPLICATION_ID=1234567890123456789
OAUTH_GITLAB_SECRET=onetwothreefourfivesix

This MR also adds the first tests to the Meltano API.

References

• Flask-Security: https://pythonhosted.org/Flask-Security/ (we are using our fork, at https://github.com/meltano/flask-security)
• Flask-Authlib: https://docs.authlib.org/en/latest/index.html