Source Zendesk Support: support oauth

[sherifnada]

Tell us about the problem you're trying to solve

With the release of Airbyte Cloud, we need to start supporting Oauth for this connector, since it's the recommended way of authenticating users into a SaaS application.

If this connector doesn't support oauth already (i.e: doesn't accept a client_id and client_secret) then we need to update its spec to accept those parameters. There are two ways to do this:

If the connector already supports some auth mechanism like api_key, I suggest that this be a oneof nested inside a top-level field called "authentication":

{ authentication: { type: object oneOf: [ // api key, // oauth ] } }

If the connector only supports webflow oauth, then no changes are needed to the properties format and we will only need to add annotations.

See the connector spec reference in the docs for reference on how a oneof can be implemented.

This should be done in a backwards compatible manner i.e: users currently supplying authentication info in the config's top-level should not be impacted by this change.

Acceptance Criteria

1. The connector supports oauth webflow authentication with client_id/client_secret in a backwards compatible manner
2. Oauth properties are annotated properly. See this PR for an example

[cheyura]

@sherifnada Public app created

[antixar]

Oauth2 logic of connectors Zendesk Support and Zendesk Talk is same. Their access tokens are fully compatible.
Python part:

Zendesk Talk
Zendesk Support

Zendesk docs
Necessary scopes' value: read
Example of consent url: https://{subdomain}.zendesk.com/oauth/authorizations/new?.....
Example of token url: https://{subdomain}.zendesk.com/oauth/tokens
where subdomain should be forwarded from UI part

The Zendesk oAuth2 implementation returns long-term access_token without refresh_token

[bazarnov]

#7086