This is asp.net core web application with one running Hosted Service, which is to be integrated with GitHub App and uses GitHub API identity to call GitHub APIs (v3 - REST).

Configuration of label subscriptions is stored in given repositories. Example: https://github.com/rokonec-int-tests/issue-notify-tests/blob/master/.github/AREAOWNERS.json. When it receives WebHook about isseu labeling, it will upsert comment mentioning given people.

For this to work given GitHub app has to set its webhook url to https://smee.io/zlcz3wSWRkhOywV (or new smee channel). This will allow to recevie and debug GitHub app webhooks - in our particular case webhook about issues labeling

npm config set strict-ssl false
smee --url https://smee.io/zlcz3wSWRkhOywV --target http://localhost:3000/api/webhooks/incoming/github

Right clict WEB project -> Manage User Secrets

Edit its content with following template

{
  "WebHooks:GitHub:SecretKey:default": "16charssecrets",
  "GitHubApp": {
    "ApplicationId": 123456,
    "InstallationId": 12345,
    "PrivateKey": {
      "KeyString": "MI...Tgw"
    }
  }
}

KeyString is .pem file (private key of GitHub app) without comment lines and \n

Right clict test project -> Manage User Secrets

Edit its content with following template

{
  "WebHooks:GitHub:SecretKey:default": "16charssecrets",
  "GitHubApp": {
    "ApplicationId": 123456,
    "InstallationId": 12345,
    "PrivateKey": {
      "KeyString": "MI...Tgw"
    }
  }
}

It is possible to use different GitHub app installtion for local debug and integration tests if needed.