build: auto start Jenkins CI via PR labels

Add an Action that will find every PR with the `request-ci` label and will start a Jenkins CI for each of these Pull Requests. The scheduler event is used to circumvent GitHub Actions limitations on Pull Requests from forks (where secrets are not accessible and the GITHUB_TOKEN is read-only). If the Action fails to start a CI, it will add a `request-ci-failed` label and will leave a comment with the error message from NCU. Fixes: nodejs/github-bot#234 PR-URL: #34089 Reviewed-By: Christian Clauss <cclauss@me.com>
Trott · Aug 2, 2020 · Jul 27, 2020 · Jul 30, 2020 · Jul 30, 2020 · Jul 27, 2020
commit 6cab3b0e261dfaedd42ca46ee04957d4ec6d1be0
diff --git a/.github/workflows/auto-start-ci.yml b/.github/workflows/auto-start-ci.yml
@@ -0,0 +1,65 @@
+---
+name: Auto Start CI
+
+on:
+  push:
+  schedule:
+    # `schedule` event is used instead of `pull_request` because when a
+    # `pull_requesst` event is triggered on a PR from a fork, GITHUB_TOKEN will
+    # be read-only, and the Action won't have access to any other repository
+    # secrets, which it needs to access Jenkins API. Runs every five minutes
+    # (fastest the scheduler can run). Five minutes is optimistic, it can take
+    # longer to run.
+    - cron: "*/5 * * * *"
+
+jobs:
+  commitQueue:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@master
+
+      # Install dependencies
+      - name: Install jq
+        run: sudo apt-get install jq -y
+      - name: Install Node.js
+        uses: actions/setup-node@v2-beta
+        with:
+          node-version: '12'
+      - name: Install node-core-utils
+        run: npm install -g node-core-utils
+
+      - name: Set variables
+        run: |
+          echo "::set-env name=REPOSITORY::$(echo ${{ github.repository }} | cut -d/ -f2)"
+          echo "::set-env name=OWNER::${{ github.repository_owner }}"
+
+      # Get Pull Requests
+      - name: Get Pull Requests
+        uses: octokit/graphql-action@v2.x
+        id: get_prs_for_ci
+        with:
+          query: |
+            query prs($owner:String!, $repo:String!) {
+              repository(owner:$owner, name:$repo) {
+                pullRequests(labels: ["request-ci"], states: OPEN, last: 100) {
+                  nodes {
+                    number
+                  }
+                }
+              }
+            }
+          owner: ${{ env.OWNER }}
+          repo: ${{ env.REPOSITORY }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Setup node-core-utils
+        run: |
+          ncu-config set username ${{ secrets.JENKINS_USER }}
+          ncu-config set token none
+          ncu-config set jenkins_token ${{ secrets.JENKINS_TOKEN }}
+          ncu-config set owner ${{ env.OWNER }}
+          ncu-config set repo ${{ env.REPOSITORY }}
+
+      - name: Start CI
+        run: ./tools/start-ci.sh ${{ secrets.GITHUB_TOKEN }} ${{ env.OWNER }} ${{ env.REPOSITORY }} $(echo '${{ steps.get_prs_for_ci.outputs.data }}' | jq '.repository.pullRequests.nodes | map(.number) | .[]')
diff --git a/tools/actions/start-ci.sh b/tools/actions/start-ci.sh
@@ -0,0 +1,53 @@
+#!/bin/bash
+
+set -xe
+
+GITHUB_TOKEN=$1
+OWNER=$2
+REPOSITORY=$3
+API_URL=https://api.github.com
+REQUEST_CI_LABEL='request-ci'
+REQUEST_CI_FAILED_LABEL='request-ci-failed'
+shift 3
+
+function issueUrl() {
+  echo "$API_URL/repos/${OWNER}/${REPOSITORY}/issues/${1}"
+}
+
+function labelsUrl() {
+  echo "$(issueUrl "${1}")/labels"
+}
+
+function commentsUrl() {
+  echo "$(issueUrl "${1}")/comments"
+}
+
+for pr in "$@"; do
+  curl -sL --request DELETE \
+       --url "$(labelsUrl "$pr")"/"$REQUEST_CI_LABEL" \
+       --header "authorization: Bearer ${GITHUB_TOKEN}" \
+       --header 'content-type: application/json'
+
+  ci_started=yes
+  rm -f output;
+  ncu-ci run "$pr" >output 2>&1 || ci_started=no
+
+  if [ "$ci_started" == "no" ]; then
+    # Do we need to reset?
+    curl -sL --request PUT \
+       --url "$(labelsUrl "$pr")" \
+       --header "authorization: Bearer ${GITHUB_TOKEN}" \
+       --header 'content-type: application/json' \
+       --data '{"labels": ["'"${REQUEST_CI_FAILED_LABEL}"'"]}'
+
+    jq -n --arg content "<details><summary>Couldn't start CI</summary><pre>$(cat output)</pre></details>" '{body: $content}' > output.json
+
+    curl -sL --request POST \
+       --url "$(commentsUrl "$pr")" \
+       --header "authorization: Bearer ${GITHUB_TOKEN}" \
+       --header 'content-type: application/json' \
+       --data @output.json
+
+    rm output.json;
+  fi
+done;