Reviewer Auto-Assign Workflow

Workflow file: .github/workflows/reviewer-autoassign.yml

Purpose

Requests reviewers based on path ownership history while preventing non-collaborator review requests.

Flow

flowchart TD
  A[PR event or manual dispatch] --> B[Resolve PR number]
  B --> C[List changed files]
  C --> D[Build candidate reviewer scores from commit history]
  D --> E[Take top candidates]
  E --> F[Filter to repository collaborators]
  F --> G{Any eligible reviewers?}
  G -->|No| H[Exit with informational no-op]
  G -->|Yes| I[Request reviewers on PR]
  I --> J[Write step summary]

Entrance

Item	Value
Trigger	pull_request_target (opened, synchronize, reopened, ready_for_review)
Manual trigger	workflow_dispatch with pr_number
Concurrency	${{ github.workflow }}-${{ github.event.pull_request.number or github.ref }}
Permissions	contents: read, pull-requests: write

Exit

Path	Exit condition
Pass	Reviewers requested successfully
No-op	No changed files, no candidates, or no eligible collaborators
Fail	PR number resolution fails or API errors propagate

Schedule

No schedule trigger.

Inputs

Input	Type	Required	Purpose
pr_number	number	Yes for manual dispatch	Target PR to evaluate

Variables and secrets

Type	Name	Used by
Env	PR_NUMBER_INPUT	Manual dispatch PR resolution

No external secrets are required.

Guardrails

1. PR author is never auto-requested.
2. Bot accounts are excluded.
3. Candidates must pass collaborator check before request.
4. Non-collaborator API responses are warned and skipped, not hard-failed.