add issues workflow

.github/workflows/issues.yml

@@ -0,0 +1,50 @@
+name: issues
+
+on:
+  issues:
+    types: [opened]
+
+jobs:
+  issues:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - run: npm install mdjson
+
+    - uses: actions/github-script@v6
+      with:
+        github-token: ${{ secrets.GITHUB_TOKEN }}
+        script: |
+          const fs = require('fs').promises;
+          const mdjson = require('mdjson');
+
+          const titles = Object.keys(mdjson(context.payload.issue.body));
+
+          for (let file of await fs.readdir('.github/ISSUE_TEMPLATE')) {
+            if (!file.endsWith('.md')) {
+              continue;
+            }
+
+            const template = await fs.readFile(`.github/ISSUE_TEMPLATE/${file}`, 'utf-8');
+            const templateTitles = Object.keys(mdjson(template));
+
+            if (templateTitles.every((title) => titles.includes(title))) {
+              process.exit(0);
+            }
+          }
+
+          await github.rest.issues.createComment({
+            owner: context.issue.owner,
+            repo: context.issue.repo,
+            issue_number: context.issue.number,
+            body: 'This issue is being automatically closed because it does not follow the issue template.',
+          });
+
+          await github.rest.issues.update({
+            owner: context.issue.owner,
+            repo: context.issue.repo,
+            issue_number: context.issue.number,
+            state: 'closed',
+          });