Automate setting closed issue milestones (#37872)

Author: roji

.github/workflows/label-and-milestone-issues.yml

@@ -0,0 +1,168 @@
+# This workflow automatically labels issues with the preview/RC version when their fixing PR
+# is merged into main or a release branch, and sets their milestone to the current version.
+# All version information is read from eng/Versions.props at the merge commit.
+
+name: Label and milestone closed issues
+
+on:
+  pull_request_target:
+    types: [closed]
+    branches:
+      - main
+      - release/**
+
+permissions:
+  issues: write
+  contents: read
+  pull-requests: read
+
+jobs:
+  label:
+    if: github.event.pull_request.merged == true
+    runs-on: ubuntu-latest
+    steps:
+      - name: Label issues and update milestones
+        uses: actions/github-script@v8
+        with:
+          script: |
+            const owner = context.repo.owner;
+            const repo = context.repo.repo;
+            const prNumber = context.payload.pull_request.number;
+            const mergeCommitSha = context.payload.pull_request.merge_commit_sha;
+
+            // Find issues closed by this PR using GraphQL (include current milestone)
+            const query = `
+              query($owner: String!, $repo: String!, $prNumber: Int!) {
+                repository(owner: $owner, name: $repo) {
+                  pullRequest(number: $prNumber) {
+                    closingIssuesReferences(first: 50) {
+                      nodes {
+                        number
+                        milestone {
+                          title
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            `;
+
+            const result = await github.graphql(query, { owner, repo, prNumber });
+            const closingIssues = result.repository.pullRequest.closingIssuesReferences.nodes;
+
+            if (closingIssues.length === 0) {
+              console.log('No closing issues linked to this PR, skipping');
+              return;
+            }
+
+            // Read version info from eng/Versions.props at the actual merge commit
+            const { data: versionFileData } = await github.rest.repos.getContent({
+              owner,
+              repo,
+              path: 'eng/Versions.props',
+              ref: mergeCommitSha
+            });
+            const versionFileContent = Buffer.from(versionFileData.content, 'base64').toString('utf-8');
+
+            const versionPrefixMatch = versionFileContent.match(/<VersionPrefix>(\d+\.\d+\.\d+)<\/VersionPrefix>/);
+            if (!versionPrefixMatch) {
+              throw new Error('Could not parse VersionPrefix from eng/Versions.props');
+            }
+            const versionPrefix = versionPrefixMatch[1];
+
+            const preReleaseLabelMatch = versionFileContent.match(/<PreReleaseVersionLabel>(preview|rc)<\/PreReleaseVersionLabel>/);
+            const preReleaseIterationMatch = versionFileContent.match(/<PreReleaseVersionIteration>(\d+)<\/PreReleaseVersionIteration>/);
+
+            let label;
+            if (preReleaseLabelMatch && preReleaseIterationMatch) {
+              label = `${preReleaseLabelMatch[1]}-${preReleaseIterationMatch[1]}`;
+            }
+
+            console.log(`Version: ${versionPrefix}, label: ${label ?? 'none'}`);
+
+            // Label all closing issues
+            // (don't filter by state to avoid race conditions where GitHub
+            // hasn't closed the issue yet when this workflow runs)
+            const errors = [];
+            if (label) {
+              for (const issue of closingIssues) {
+                console.log(`Adding label '${label}' to issue #${issue.number}`);
+                try {
+                  await github.rest.issues.addLabels({
+                    owner,
+                    repo,
+                    issue_number: issue.number,
+                    labels: [label]
+                  });
+                } catch (error) {
+                  errors.push(`Failed to add label to issue #${issue.number}: ${error.message}`);
+                }
+              }
+            }
+
+            // Look up the target milestone (e.g. "11.0.0", "10.0.5") via GraphQL
+            const targetMilestoneName = versionPrefix;
+            const milestoneResult = await github.graphql(`
+              query($owner: String!, $repo: String!, $title: String!) {
+                repository(owner: $owner, name: $repo) {
+                  milestones(query: $title, first: 1) {
+                    nodes {
+                      number
+                      title
+                    }
+                  }
+                }
+              }
+            `, { owner, repo, title: targetMilestoneName });
+            const milestoneNode = milestoneResult.repository.milestones.nodes
+              .find(m => m.title === targetMilestoneName);
+            if (!milestoneNode) {
+              throw new Error(`Milestone '${targetMilestoneName}' not found`);
+            }
+
+            // Set the milestone on closing issues, applying a "min" strategy:
+            // only update if the issue has no version milestone or the target is earlier
+            const targetVersion = parseVersion(versionPrefix);
+            for (const issue of closingIssues) {
+              const currentTitle = issue.milestone?.title;
+              const currentVersion = currentTitle ? parseVersion(currentTitle) : null;
+
+              if (currentVersion && compareVersions(currentVersion, targetVersion) <= 0) {
+                console.log(`Issue #${issue.number} already has milestone '${currentTitle}' <= '${targetMilestoneName}', skipping`);
+                continue;
+              }
+
+              const from = currentTitle ? `'${currentTitle}'` : 'none';
+              console.log(`Setting milestone on issue #${issue.number} from ${from} to '${targetMilestoneName}'`);
+              try {
+                await github.rest.issues.update({
+                  owner,
+                  repo,
+                  issue_number: issue.number,
+                  milestone: milestoneNode.number
+                });
+              } catch (error) {
+                errors.push(`Failed to set milestone on issue #${issue.number}: ${error.message}`);
+              }
+            }
+
+            if (errors.length > 0) {
+              throw new Error(`Errors processing issues:\n${errors.join('\n')}`);
+            }
+
+            console.log(`Done. Processed ${closingIssues.length} issue(s) with label '${label ?? 'none'}' and milestone '${targetMilestoneName}'`);
+
+            // Parses a milestone title as a semver version, or returns null for
+            // non-version milestones (e.g. "Backlog", "MQ", "Discussions")
+            function parseVersion(title) {
+              const m = title.match(/^(\d+)\.(\d+)\.(\d+)$/);
+              return m ? [parseInt(m[1]), parseInt(m[2]), parseInt(m[3])] : null;
+            }
+
+            function compareVersions(a, b) {
+              for (let i = 0; i < 3; i++) {
+                if (a[i] !== b[i]) return a[i] - b[i];
+              }
+              return 0;
+            }