Add nightly build test scripts

Author: gasman

.github/report_nightly_build_failure.py

@@ -0,0 +1,28 @@
+
+"""
+Called by GitHub Action when the nightly build fails.
+This reports an error to the #nightly-build-failures Slack channel.
+"""
+import os
+import requests
+
+if "SLACK_WEBHOOK_URL" in os.environ:
+    # https://docs.github.com/en/free-pro-team@latest/actions/reference/environment-variables#default-environment-variables
+    repository = os.environ["GITHUB_REPOSITORY"]
+    run_id = os.environ["GITHUB_RUN_ID"]
+    url = f"https://github.com/{repository}/actions/runs/{run_id}"
+
+    print("Reporting to #nightly-build-failures slack channel")
+    response = requests.post(
+        os.environ["SLACK_WEBHOOK_URL"],
+        json={
+            "text": f"A Nightly build failed. See {url}",
+        },
+    )
+
+    print(f"Slack responded with: {response}")
+
+else:
+    print(
+        "Unable to report to #nightly-build-failures slack channel because SLACK_WEBHOOK_URL is not set"
+    )

.github/workflows/nightly-tests.yml

@@ -0,0 +1,35 @@
+name: Nightly Wagtail test
+
+on:
+  schedule:
+    - cron: "20 1 * * *"
+
+  workflow_dispatch:
+
+jobs:
+  nightly-test:
+    # Cannot check the existence of secrets, so limiting to repository name to prevent all forks to run nightly.
+    # See: https://github.com/actions/runner/issues/520
+    if: ${{ github.repository == 'torchbox/wagtail-experiments' }}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python 3.9
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.9
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install "git+https://github.com/wagtail/wagtail.git@main#egg=wagtail"
+          pip install -e .[testing]
+      - name: Test
+        id: test
+        continue-on-error: true
+        run: ./runtests.py
+      - name: Send Slack notification on failure
+        if: steps.test.outcome == 'failure'
+        run: |
+          python .github/report_nightly_build_failure.py
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}