[JENKINS-25612] Add PropertyFileCredentials provider

Use-cases for StandardUsernamePasswordCredentials coming from property files:

• Usage of local credential files stored on Jenkins Server (e.g. .github file being used in github-api)


• Using credentials from URL

The implementation must notify users that the implementation is not secure and they take the full responsibility.

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Originally reported by oleg_nenashev, imported from: Add PropertyFileCredentials provider

• status: Open
  
• priority: Minor
  
• component(s): plain-credentials-plugin
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 2
  
• imported: 20260604-161841
  

Raw content of original issue

Use-cases for StandardUsernamePasswordCredentials coming from property files:



	
Usage of local credential files stored on Jenkins Server (e.g. .github file being used in github-api)

	
Using credentials from URL



The implementation must notify users that the implementation is not secure and they take the full responsibility. 

No files or tests are named in the issue. Start by reviewing the plain-credentials-plugin entry points for StandardUsernamePasswordCredentials and determine how a PropertyFileCredentials provider would support local files and URLs. Done should include an explicit warning that the approach is insecure and leaves responsibility with users.

Written by the indexing model from the issue text.