HMS-3162: tests: add initial testing farm integration

.github/workflows/testingfarm.yml

@@ -0,0 +1,52 @@
+---
+name: Testing farm tests
+
+on:
+  pull_request_target:
+    types: [opened, synchronize, reopened]
+
+# To use testing farm we need the TF_API_KEY secret available inside the
+# forked repo which requires the pull_request_target trigger. To protect
+# the secrets we need to make sure only people with repo write access
+# can trigger this workflow. This means that ouside contributors will
+# get an initial failure when the workflow is run. But once someone from
+# the team re-triggers it it will work.
+#
+# Note that "pull_requqest_target" events are always triggered even
+# when the "Fork pull request workflows from outside collaborators"
+# setting is restricted to "Require approval for all outside collaborators"
+# (see https://docs.github.com/en/actions/managing-workflow-runs/approving-workflow-runs-from-public-forks)
+#
+# Note also that this precautions might be overkill because a fork
+# cannot modify this workflow and all we do is run a branch inside
+# testing farm. But a) the scope of workflow may expand over time
+# b) it feels safer this way and is not a big burden in practise.
+#
+# This follows https://michaelheap.com/access-secrets-from-forks/
+jobs:
+  testingfarm:
+    name: "Run in testing farm"
+    runs-on: ubuntu-latest
+    steps:
+    - name: Get User Permission
+      id: checkAccess
+      uses: actions-cool/check-user-permission@v2
+      with:
+        require: write
+        username: ${{ github.triggering_actor }}
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    - name: Check User Permission
+      if: steps.checkAccess.outputs.require-result == 'false'
+      run: |
+        echo "${{ github.triggering_actor }} does not have permissions on this repo."
+        echo "Current permission level is ${{ steps.checkAccess.outputs.user-permission }}"
+        echo "Job originally triggered by ${{ github.actor }}"
+        exit 1
+    - name: Run the tests
+      uses: sclorg/testing-farm-as-github-action@v1
+      with:
+        api_key: ${{ secrets.TF_API_KEY }}
+        git_url: ${{ github.event.pull_request.head.repo.clone_url }}
+        git_ref: ${{ github.event.pull_request.head.ref }}
+        pull_request_status_name: "Testing farm"