[ci-skip] add PR jar workflows used by Paper

.github/workflows/build_pr.yml

@@ -0,0 +1,81 @@
+# Here lie dragons!
+#
+# This action builds a jar to be updated in the body
+# of the PR relating to this action.
+#
+# Created by PaperMC contributors for Paper, modified by granny
+
+name: Build Pl3xMap PR
+on:
+  pull_request:
+    types:
+      - opened
+      - reopened
+      - synchronize
+      - labeled
+
+jobs:
+  build:
+    # Run on all label events (won't be duplicated) or all push events or on PR syncs not from the same repo
+    if: (github.event_name == 'pull_request' && github.event.action == 'labeled') || github.event_name != 'pull_request' || github.repository != github.event.pull_request.head.repo.full_name
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        java: [17]
+      fail-fast: true
+    steps:
+      - uses: actions/checkout@v4
+      - name: JDK ${{ matrix.java }}
+        uses: actions/setup-java@v4
+        with:
+          java-version: ${{ matrix.java }}
+          distribution: 'temurin'
+
+      - name: Validate Gradle wrapper
+        uses: gradle/wrapper-validation-action@v1
+      - name: Setup Gradle
+        uses: gradle/gradle-build-action@v2
+
+      - name: Configure Build
+        uses: actions/github-script@v6
+        id: determine
+        with:
+          script: |
+            const {owner, repo} = context.repo;
+            const event_name = "${{ github.event_name }}";
+            const event = ${{ toJSON(github.event) }};
+            const ref_type = "${{ github.ref_type }}";
+            const ref_name = "${{ github.ref_name }}";
+            const result = {
+              action: "build"
+            };
+
+            if (event_name === "pull_request" && event.pull_request.labels.find((l) => l.name === "build-pr-jar")) {
+              result["pr"] = event.pull_request.number;
+              result["action"] = "pl3xmap";
+              core.notice(`This is a pull request action with a build pl3xmap label (${JSON.stringify(result)})`);
+              return result;
+            }
+            core.notice("This will not build a pl3xmap jar");
+            return result;
+
+      - name: Build
+        run: ./gradlew build --stacktrace
+
+      - name: Upload Pl3xMap Jar
+        if: fromJSON(steps.determine.outputs.result).action == 'pl3xmap'
+        uses: actions/upload-artifact@v4
+        with:
+          name: pl3xmap-${{ fromJSON(steps.determine.outputs.result).pr }}
+          path: build/libs/Pl3xMap-*-SNAPSHOT.jar
+  event_file:
+    name: "Event File"
+    # Only run on PRs if the source branch is on someone else's repo
+    if: ${{ github.event_name != 'pull_request' || github.repository != github.event.pull_request.head.repo.full_name }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Upload
+        uses: actions/upload-artifact@v4
+        with:
+          name: Event File
+          path: ${{ github.event_path }}

.github/workflows/pr_comment.yml

@@ -0,0 +1,78 @@
+# This workflow run on the completion of the
+# build workflow but only does anything if the
+# triggering workflow uploaded an artifact.
+#
+# Do note that it is then the trigger workflow that
+# determines if this will update the PR text body. All
+# this workflow does is check if an uploaded artifact
+# exists and there is a PR tied to the previous workflow.
+#
+# Created by PaperMC contributors for Paper, modified by granny
+
+name: Comment on pull request
+on:
+  workflow_run:
+    workflows: ['Build Pl3xMap PR']
+    types: [completed]
+jobs:
+  pr_comment:
+    if: github.event.workflow_run.conclusion == 'success'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/github-script@v6
+        with:
+          # This snippet is public-domain, taken from
+          # https://github.com/oprypin/nightly.link/blob/master/.github/workflows/pr-comment.yml
+          # Modified extensively by Machine_Maker
+          script: |
+            async function updatePR(owner, repo, issue_number, purpose, body) {
+              const { data } = await github.rest.issues.get({ owner, repo, issue_number });
+              core.debug(JSON.stringify(data, null, 2));
+
+              const marker = `<!-- bot: ${purpose} -->`;
+
+              let new_body = data.body ? data.body.trim().split(marker)[0].trim() : "";
+              new_body += `\n${marker}\n---\n${body}`;
+
+              core.info(`Updating the text body of PR #${issue_number} in ${owner}/${repo}`);
+              await github.rest.issues.update({ owner, repo, issue_number, body: new_body });
+            }
+
+            const { owner, repo } = context.repo;
+            const run_id = ${{ github.event.workflow_run.id }};
+            const repo_id = ${{ github.event.repository.id }};
+
+            let pulls = [];
+            const event_type = "${{ github.event.workflow_run.event}}";
+            if (event_type === "push") { // if push, it's from the same repo which means `pull_requests` is populated
+              pulls = ${{ toJSON(github.event.workflow_run.pull_requests) }};
+            } else {
+              const pr_branch = "${{ github.event.workflow_run.head_branch }}";
+              const pr_sha = "${{ github.event.workflow_run.head_sha }}";
+              const pr_owner = "${{ github.event.workflow_run.head_repository.owner.login }}";
+              const { data } = await github.rest.pulls.list({ owner, repo, head: `${pr_owner}:${pr_branch}`, state: "open" });
+              core.debug(JSON.stringify(data, null, 2));
+              pulls = data.filter((pr) => pr.head.sha === pr_sha && pr.labels.find((l) => l.name === "build-pr-jar"));
+            }
+
+            if (!pulls.length) {
+              return core.notice("This workflow doesn't have any pull requests!");
+            } else if (pulls.length > 1) {
+              core.info(JSON.stringify(pulls, null, 2));
+              return core.error("Found multiple matching PRs");
+            }
+            const pull_request = pulls[0];
+
+            const artifacts = await github.paginate(github.rest.actions.listWorkflowRunArtifacts, { owner, repo, run_id });
+            if (!artifacts.length) {
+              return core.info("Skipping comment due to no artifact found");
+            }
+            const artifact = artifacts.find((art) => art.name === `pl3xmap-${pull_request.number}`);
+            if (!artifact) {
+              return core.info("Skipping comment to no matching artifact found");
+            }
+
+            const link = `https://nightly.link/${owner}/${repo}/actions/artifacts/${artifact.id}.zip`;
+            const body = `Download the pl3xmap jar for this pull request: [${artifact.name}.zip](${link})`;
+            core.info(`Adding a link to ${link}`);
+            await updatePR(owner, repo, pull_request.number, "pl3xmap-pr-build", body);