More Webhook support

The current design only allows for 1 webhook endpoint to be configured (with basic authentication supported).

I’d like to extend this by allowing 1 extra environment variable to be injected WEBHOOK_ARRAY_FILE which points to a JSON file with data that looks like below:

[
  {
    "WEBHOOK_URL": "https://webhook_dev.example.com"
  },
  {
    "WEBHOOK_URL": "https://webhook_test.example.com",
    "WEBHOOK_USERNAME": "myhookuser",
    "WEBHOOK_PASSWORD": "mylongandsupersecurehookpassword"
  }
]

This file can be mounted onto the docker container and the path passed in via WEBHOOK_ARRAY_FILE. The existing functionality will not be broken and users can now add multiple webhook endpoints when secrets are updated.

[ryan-lane]

Oh, hah. I raised the concerns, right. Let me re-evaluate my thoughts there.

[edify42]

Indeed @egeland I don’t! - Happy for you to take over this PR if you’re keen 😃