feat: use new action

.github/workflows/deploy-prs.yml

@@ -0,0 +1,132 @@
+name: Deploy Preview
+on: [pull_request]
+
+jobs:
+  vercel-deployment:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: aulneau/vercel-action@v19.0.2+3
+        id: vercel_deployment_preview
+        if: github.event_name == 'pull_request'
+        with:
+          vercel-token: ${{ secrets.VERCEL_TOKEN }}
+          vercel-org-id: ${{ secrets.VERCEL_ORG_ID }}
+          vercel-project-id: ${{ secrets.VERCEL_PROJECT_ID }}
+          scope: ${{ secrets.VERCEL_SCOPE }}
+          alias-domains: pr-{{ PR_NUMBER }}.docs.stacks.engineering
+      - id: file_changes
+        name: Check diff of PR
+        uses: trilom/file-changes-action@v1.2.3
+        with:
+          prNumber: ${{ github.event.pull_request.number }}
+      - name: Comment on PR
+        uses: actions/github-script@v2
+        id: comment
+        if: github.event_name == 'pull_request'
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          script: |
+            const getPageUrl = (changed) => {
+              const pageUrl = changed.replace('src/pages/', '/').replace('.md', '')
+              if(pageUrl === '/index') return '/'
+              return pageUrl
+            }
+
+            const makeUrl = (path, url) => `${url}${path}`
+            const getScreenshotUrl = (path, url) => `https://api.microlink.io/?url=${makeUrl(path, url)}&meta=false&screenshot=&overlay.browser=dark&screenshot&embed=screenshot.url`
+
+            const getChangedPages = (changed, url) => {
+              let changedPages = []
+              changed.forEach(file => {
+                if(file.includes('src/pages')){
+                  const path = getPageUrl(file)
+                  changedPages.push({
+                    url: makeUrl(path, url),
+                    screenshot: getScreenshotUrl(path, url)
+                  })
+                }
+              })
+                // group by screenshots by 3
+              const grouped = changedPages.reduce((pv, cv, i) => {
+                const j = Math.floor(i / 2)
+                ;(pv[j] || (pv[j] = [])).push(cv)
+                return pv
+              }, [])
+
+              return grouped
+            }
+
+            const ellipsis = (txt, l = 25) => {
+              return txt.length > l ? `…${txt.slice(-22)}` : txt;
+            };
+
+            const escapeLinkTitle = txt => {
+              // escape [ and ] with \
+              return txt.replace(/\[/g, '\\[').replace(/\]/g, '\\]');
+            };
+
+            const createChangedPagesMarkdown = (changed, url) => {
+              if(changed.length === 0) return ''
+              const grouped = getChangedPages(changed, url)
+              if(grouped.length === 0) return ''
+              let md = `
+            #### 📝  Changed routes:`
+              md += grouped
+                .map(
+                  group => `
+            |${group
+                  .map(({ url: routeUrl }) => ` [**${escapeLinkTitle(ellipsis(routeUrl.replace(url, '')))}**](${routeUrl}) |`)
+                  .join('')}
+            |${':-:|'.repeat(group.length)}
+            |${group
+                  .map(
+                    ({ url: routeUrl, screenshot }) =>
+                      `<a href="${routeUrl}"><img src="${screenshot}" alt="Screenshot of ${routeUrl.replace(url, '')}" width="420"></a>` +
+                      '<br />' +
+                      `<sup><a href="${screenshot}">(view full size)</a>` +
+                      ' |'
+                  )
+                  .join('')}
+            `).join('');
+              return md
+            }
+
+            const firstLine = `Blockstack docs have been deployed with Vercel using the code from this PR!`;
+            const {data} = await github.issues.listComments({
+              ...context.repo,
+              issue_number: context.issue.number,
+            });
+            const vercelPreviewURLComment = data.find((comment) =>
+              comment.body.includes(firstLine)
+            );
+            const commentId = vercelPreviewURLComment && vercelPreviewURLComment.id || undefined;
+
+            const prUrl = '${{steps.vercel_deployment_preview.outputs.preview-url}}'
+            const changed = ${{steps.file_changes.outputs.files_modified}}
+            const added = ${{steps.file_changes.outputs.files_added}}
+
+            const commentBody = `
+            #### Blockstack Documentation
+            ${ firstLine }
+
+            - [Blockstack Docs](${prUrl})
+            ${createChangedPagesMarkdown([...changed, ...added], prUrl)}
+            Built with commit ${context.sha}.
+            `;
+
+            if (context.issue.number) {
+              if (commentId) {
+                await github.issues.updateComment({
+                  ...context.repo,
+                  comment_id: commentId,
+                  body: commentBody,
+                });
+              } else {
+                await github.issues.createComment({
+                  ...context.repo,
+                  issue_number: context.issue.number,
+                  body: commentBody,
+                });
+              }
+            }