CODEOWNERS-Driven Reviewer Assignment

Overview

This flow replaces GitHub's static CODEOWNERS file with a flexible, data-driven alternative that lives in Dataverse. When a pull request is opened (or marked ready for review, or reopened) in a watched repository, the flow reads a Dataverse-backed CODEOWNERS map, matches the PR's changed file paths against the patterns in that map, requests the corresponding GitHub users as reviewers on the PR, and posts a notification card to a Teams channel summarizing who was assigned.

Use Case

Static CODEOWNERS files ship in a repo and can only be updated via a PR. Teams that need dynamic ownership — rotating on-call reviewers, temporary subject-matter experts during a migration, or reviewer pools that differ by product line — outgrow the static file quickly. By sourcing the map from Dataverse, ownership can be managed from a Power App or a Dataverse table editor without touching source control, and the same map can be reused across multiple repositories or extended with extra metadata (SLA, backup reviewer, team alias).

Flow Architecture

Environment Variables

Connectors & Connections

Note — All connections are referenced as solution connection references; the flow is portable between environments as long as a connection is mapped at import time.

Customization Guide

Almost every realistic variant of this flow can be implemented by changing environment variable values. A few cases require small edits inside the flow definition — those are called out explicitly below.

Pattern matching

The default startsWith comparison behaves like a prefix matcher. To support full glob-style patterns (**/*.tsx, src/*.cs, etc.), replace the Filter array expression with a custom match function — either a Select+Compose chain using split/indexOf or a child flow that calls a small Office Script / Azure Function. startsWith covers the common 'own everything under this folder' case cleanly.

Additional metadata

Extend the Dataverse table with columns like flowlibs_backuplogin, flowlibs_teamalias, or flowlibs_sladays. Update the loop to conditionally append the backup login when the primary user is inactive, or use the team alias in the Teams message for better routing.

Repo fan-out

Wrap the flow in a child-flow pattern: a parent flow iterates a list of repositories from Dataverse and calls this flow once per repo, passing the owner/repo/table/channel parameters dynamically. The current build is single-repo by design to keep the trigger simple.

Non-PR events

The OR condition keeps this focused on opened, ready_for_review, and reopened. To also handle synchronize (new commits pushed), add a fourth equals row — but know that this will re-post to Teams on every push.

Key Expressions

The flow is intentionally light on Power Fx / WDL gymnastics — the heaviest expressions are the branch-name concatenation and the approval outcome check. They are listed below in the order they appear in the flow.

startsWith(item()?['filename'], items('For_Each_CODEOWNERS_Rule')?['flowlibs_pathpattern'])

union(variables('varReviewers'), variables('varReviewers'))

concat('<p><strong>Reviewers assigned to PR #', triggerOutputs()?['body/number'], '</strong> in <em>', variables('varGitHubOwner'), '/', variables('varGitHubRepo'), '</em>:</p><p>Reviewers: ', join(outputs('Deduplicate_Reviewers'), ', '), '</p><p><a href="', triggerOutputs()?['body/pull_request/html_url'], '">Open the pull request</a></p>')

@or(equals(triggerOutputs()?['body/action'], 'opened'), equals(triggerOutputs()?['body/action'], 'ready_for_review'), equals(triggerOutputs()?['body/action'], 'reopened'))