ci(workflow): post build result as comment

.github/workflows/comment-pr.yml

@@ -0,0 +1,55 @@
+name: Comment on the pull request
+
+on:
+  workflow_run:
+    workflows: ["free-programming-books-lint"]
+    types:
+      - completed
+
+jobs:
+  upload:
+    permissions:
+      pull-requests: write
+    runs-on: ubuntu-latest
+    if: >
+      ${{ github.event.workflow_run.event == 'pull_request' &&
+      github.event.workflow_run.conclusion == 'success' }}
+    steps:
+      - name: 'Download artifact'
+        uses: actions/github-script@v6
+        with:
+          script: |
+            let allArtifacts = await github.rest.actions.listWorkflowRunArtifacts({
+               owner: context.repo.owner,
+               repo: context.repo.repo,
+               run_id: context.payload.workflow_run.id,
+            });
+            let matchArtifact = allArtifacts.data.artifacts.filter((artifact) => {
+              return artifact.name == "pr"
+            })[0];
+            let download = await github.rest.actions.downloadArtifact({
+               owner: context.repo.owner,
+               repo: context.repo.repo,
+               artifact_id: matchArtifact.id,
+               archive_format: 'zip',
+            });
+            let fs = require('fs');
+            fs.writeFileSync(`${process.env.GITHUB_WORKSPACE}/pr.zip`, Buffer.from(download.data));
+
+      - name: 'Unzip artifact'
+        run: unzip pr.zip
+
+      - name: 'Comment on PR'
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          if [ -s error.log ]
+          then
+            gh pr comment $(<PRurl) -b "Linter failed, fix the error(s):
+            \`\`\`
+            $(cat error.log)
+            \`\`\`"
+            gh pr edit $(<PRurl) --add-label "linter error"
+          else
+            gh pr edit $(<PRurl) --remove-label "linter error"
+          fi

.github/workflows/fpb-lint.yml

@@ -1,6 +1,6 @@
 name: free-programming-books-lint
 
-on: [push, pull_request]
+on: [pull_request]
 
 permissions:
   contents: read
@@ -17,7 +17,20 @@ jobs:
       with:
         node-version: '16.x'
     - run: npm install -g free-programming-books-lint
-    - run: fpb-lint ./books/
-    - run: fpb-lint ./casts/
-    - run: fpb-lint ./courses/
-    - run: fpb-lint ./more/
+
+    - name: Pull Request
+      run: |
+        fpb-lint books casts courses more &> output.log
+
+    - name: Clean output and create artifacts
+      if: always()
+      run: |
+          mkdir -p ./pr
+          echo ${{ github.event.pull_request.html_url }} > ./pr/PRurl
+          cat output.log | sed -E 's:/home/runner/work/free-programming-books/|⚠.+::' | uniq > ./pr/error.log
+
+    - uses: actions/upload-artifact@v3
+      if: always()
+      with:
+        name: pr
+        path: pr/