1 files changed, 59 insertions, 0 deletions
diff --git a/taskcluster/scripts/are_dependencies_completed.py b/taskcluster/scripts/are_dependencies_completed.py
new file mode 100755
index 0000000000..79a0bb30c3
--- /dev/null
+++ b/taskcluster/scripts/are_dependencies_completed.py
@@ -0,0 +1,59 @@
+#!/usr/bin/env python3
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import argparse
+import os
+
+import taskcluster
+
+queue = taskcluster.Queue(
+    {
+        "rootUrl": os.environ.get("TASKCLUSTER_PROXY_URL", "https://taskcluster.net"),
+    }
+)
+
+
+def check_all_dependencies_are_completed(current_task_id):
+    print(f"Fetching task definition of {current_task_id}...")
+    task = queue.task(current_task_id)
+    dependencies_task_ids = task["dependencies"]
+
+    print(f"Fetching status of {len(dependencies_task_ids)} dependencies...")
+    # TODO Make this dict-comprehension async once we go Python 3
+    state_per_task_ids = {
+        task_id: queue.status(task_id)["status"]["state"]
+        for task_id in dependencies_task_ids
+    }
+    print("Statuses fetched.")
+    non_completed_tasks = {
+        task_id: state
+        for task_id, state in state_per_task_ids.items()
+        if state != "completed"
+    }
+
+    if non_completed_tasks:
+        raise ValueError(f"Some tasks are not completed: {non_completed_tasks}")
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description='Errors out if one of the DEPENDENCY_TASK_ID does not have the Taskcluster status "completed"'
+    )
+
+    parser.add_argument(
+        "current_task_id",
+        metavar="CURRENT_TASK_ID",
+        help="The task ID of the current running task",
+    )
+
+    result = parser.parse_args()
+    check_all_dependencies_are_completed(result.current_task_id)
+    print("All dependencies are completed. Reporting a green task!")
+    exit(0)
+
+
+if __name__ == "__main__":
+    main()