[JENKINS-66366] Credential test does not detect missing access to collaborators

When specifying a valid GH credential to access a public GH repo (e.g. in jenkinsci), it tests as successful:

Credentials ok. Connected to https://github.com/jenkinsci/matrix-auth-plugin.

But when running the pipeline with the default branch discovery (discover PRs, trust users with Admin/Write access), exceptions will occur during the scan that the /collaborators URL is inaccessible.

```
java.io.FileNotFoundException: https://api.github.com/repos/jenkinsci/matrix-auth-plugin/collaborators/daniel-beck/permission
```

I'd expect a warning in the credential validation test. While a pipeline can be configured to not need permission lookup, given it's both common and the default, that seems like a bug.

---
Originally reported by danielbeck, imported from: Credential test does not detect missing access to collaborators

• status: Open
  
• priority: Minor
  
• component(s): github-branch-source-plugin
  
• resolution: Unresolved
  
• votes: 1
  
• watchers: 5
  
• imported: 2025-12-02
  

Raw content of original issue

When specifying a valid GH credential to access a public GH repo (e.g. in jenkinsci), it tests as successful:

Credentials ok. Connected to https://github.com/jenkinsci/matrix-auth-plugin.

But when running the pipeline with the default branch discovery (discover PRs, trust users with Admin/Write access), exceptions will occur during the scan that the /collaborators URL is inaccessible.



java.io.FileNotFoundException: https://api.github.com/repos/jenkinsci/matrix-auth-plugin/collaborators/daniel-beck/permission 



I'd expect a warning in the credential validation test. While a pipeline can be configured to not need permission lookup, given it's both common and the default, that seems like a bug.