CI: attempt to serialize test runs (prebid#14049)

* Try to gauge running session from browserstack

* automate, not app automate; separate to its own workflow

* reintroduce retries

* check on every chunk

* jobs not steps

* do not wait when not using browserstack

* composite actions

* remove stale yml

* fix path

Author: dgirardi

.github/actions/wait-for-browserstack/action.yml

@@ -0,0 +1,32 @@
+name: Wait for browserstack sessions
+description: Wait until enough browserstack sessions have become available
+inputs:
+  BROWSERSTACK_USER_NAME:
+    description: "Browserstack user name"
+  BROWSERSTACK_ACCESS_KEY:
+    description: "Browserstack access key"
+
+runs:
+  using: 'composite'
+  steps:
+    - env:
+        BROWSERSTACK_USERNAME: ${{ inputs.BROWSERSTACK_USER_NAME }}
+        BROWSERSTACK_ACCESS_KEY: ${{ inputs.BROWSERSTACK_ACCESS_KEY }}
+      shell: bash
+      run: |
+        while            
+          status=$(curl -u "${BROWSERSTACK_USERNAME}:${BROWSERSTACK_ACCESS_KEY}" \
+            -X GET "https://api-cloud.browserstack.com/automate/plan.json" 2> /dev/null);
+          running=$(jq '.parallel_sessions_running' <<< $status)
+          max_running=$(jq '.parallel_sessions_max_allowed' <<< $status)
+          queued=$(jq '.queued_sessions' <<< $status)
+          max_queued=$(jq '.queued_sessions_max_allowed' <<< $status)
+          spare=$(( ${max_running} + ${max_queued} - ${running} - ${queued} ))
+          required=6
+          echo "Browserstack status: ${running} sessions running, ${queued} queued, ${spare} free"
+          (( ${required} > ${spare} ))
+        do
+          delay=$(( 60 + $(shuf -i 1-60 -n 1) ))
+          echo "Waiting for ${required} sessions to free up, checking again in ${delay}s"
+          sleep $delay
+        done

.github/workflows/test-chunk.yml

@@ -67,11 +67,18 @@ jobs:
           local-testing: start
           local-identifier: random
 
+      - name: 'Wait for browserstack'
+        if: ${{ inputs.serialize }}
+        uses: ./.github/actions/wait-for-browserstack
+        with:
+          BROWSERSTACK_USER_NAME: ${{ secrets.BROWSERSTACK_USER_NAME }}
+          BROWSERSTACK_ACCESS_KEY: ${{ secrets.BROWSERSTACK_ACCESS_KEY }}
+
       - name: Run tests
         uses: nick-fields/retry@v3
         with:
           timeout_minutes: 8
-          max_attempts: 1
+          max_attempts: 3
           command: ${{ inputs.cmd }}
 
       - name: 'BrowserStackLocal Stop'

.github/workflows/test.yml

@@ -110,6 +110,7 @@ jobs:
     secrets:
       BROWSERSTACK_USER_NAME: ${{ secrets.BROWSERSTACK_USER_NAME }}
       BROWSERSTACK_ACCESS_KEY: ${{ secrets.BROWSERSTACK_ACCESS_KEY }}
+
   test-e2e:
     name: "End-to-end tests"
     needs: checkout
@@ -145,11 +146,17 @@ jobs:
           local-testing: start
           local-identifier: random
 
+      - name: 'Wait for browserstack'
+        uses: ./.github/actions/wait-for-browserstack
+        with:
+          BROWSERSTACK_USER_NAME: ${{ secrets.BROWSERSTACK_USER_NAME }}
+          BROWSERSTACK_ACCESS_KEY: ${{ secrets.BROWSERSTACK_ACCESS_KEY }}
+
       - name: Run tests
         uses: nick-fields/retry@v3
         with:
           timeout_minutes: 20
-          max_attempts: 1
+          max_attempts: 3
           command: npx gulp e2e-test
 
       - name: 'BrowserStackLocal Stop'