OAuth implementation

[SravanThotakura05]

Currently we have finalised the below approach which is implemented for other connectors.

To use the OAuth 2.0 Client Credentials Grant, configure the following parameters.

Token Provider URL: The endpoint URL to acquire new access tokens.
Client ID: The identifier for the application requesting the token.
Client Secret: A secret known only to the application and the authorization server.
Scope: (Optional) The scope of the access request.
Resource: (Optional) The target resource for the access token.
Audience: (Optional) The intended audience for the token.
Refresh Buffer Time: The absolute time period in which the application will fetch a new token to keep the connection alive.
Custom Parameters: (Optional) Additional HTTP token request parameters.

The application during the start will fetch the access token and connects to Solace. Based on Refresh Buffer Time(which ideally should be less than token expiry time) we will send a request to fetch new access token and update the current solace session to use new token.

Considerations:

1. We need http client dependency
2. Enabling/Disabling SSL on token provider URL

[SravanThotakura05]

@ozangunalp we have drafted the configurations required for OAuth implementation in Quarkus Extension for Solace.

[ozangunalp]

I think you can get some inspiration from the https://github.com/Apicurio/apicurio-common-rest-client
In Quarkus we are using the vertx client module. It depends on vertx-web-client and jackson databind.

[ozangunalp]

And even better, there is an oauth2 client extension with built-in token refresh : https://quarkus.io/guides/security-openid-connect-client-reference