ci: add a spam comment detection

.github/workflows/spam-comment-detection.yaml

@@ -0,0 +1,46 @@
+name: Spam detection
+
+on:
+  issue_comment:
+    types: [created, edited]
+
+jobs:
+  detect-spam:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Set up Node.js
+        uses: actions/setup-node@main
+
+      - name: Check for Spam
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const comment = process.env.COMMENT_BODY.toLowerCase()
+            const spam_words = process.env.SPAM_WORDS.split(',').map(w => w.toLowerCase())
+            const comment_id = process.env.COMMENT_ID
+            const issue_number = process.env.ISSUE_NUMBER
+            const owner = process.env.REPO_OWNER
+            const repo = process.env.REPO_NAME
+            const EXTERNAL_LINK_REGEXT = /https:\/\/(?!((\w+\.)?github\.com|github\.com|(\w+\.)?magickbase\.com|(\w+\.)?nervos\.org))/gi
+            if (spam_words.some(w => comment.includes(w))) {
+              console.info(`Spam comment: ${comment}`)
+              github.rest.issues.deleteComment({ owner, repo, comment_id })
+            } else if (EXTERNAL_LINK_REGEXT.test(comment)) {
+              console.info(`External link detected, append an annotation`)
+              github.rest.issues.createComment({
+                owner,
+                repo,
+                issue_number,
+                body: `An external link is mentioned in the comment above. Please verify the link's safety before visiting.`
+              })
+            } else {
+              console.info("No spam detected")
+            }
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          COMMENT_BODY: ${{ github.event.comment.body }}
+          COMMENT_ID: ${{ github.event.comment.id }}
+          ISSUE_NUMBER: ${{ github.event.issue.number }}
+          REPO_OWNER: ${{github.repository_owner }}
+          REPO_NAME: ${{ github.event.repository.name }}
+          SPAM_WORDS: ${{ github.secrets.SPAM_WORDS }}