chore: document

Author: rubenfonseca

Diff for: parallel_run_e2e.py

@@ -8,7 +8,7 @@ def main():
     features = Path("tests/e2e").rglob("infrastructure.py")
     workers = len(list(features)) - 1
 
-    command = f"poetry run pytest -n {workers} --dist loadgroup -o log_cli=true tests/e2e"
+    command = f"poetry run pytest -n {workers} -o log_cli=true tests/e2e"
     result = subprocess.run(command.split(), shell=False)
     sys.exit(result.returncode)
 

Diff for: tests/e2e/conftest.py

@@ -1,4 +1,5 @@
 import pytest
+from xdist.scheduler import LoadGroupScheduling
 
 from tests.e2e.utils.infrastructure import call_once
 from tests.e2e.utils.lambda_layer.powertools_layer import LocalLambdaPowertoolsLayer
@@ -27,3 +28,11 @@ def lambda_layer_build(tmp_path_factory: pytest.TempPathFactory, worker_id: str)
         tmp_path_factory=tmp_path_factory,
         worker_id=worker_id,
     )
+
+
+# Hook to use the xdist_group to decide how to schedule tests among the different workers.
+# Each test needs to be marked with @pytest.mark.xdist_group(name=...). This way, all
+# the tests on each directory will be scheduled on the same worker, thus sharing the
+# infrastructure.
+def pytest_xdist_make_scheduler(config, log):
+    return LoadGroupScheduling(config, log)

Diff for: tests/e2e/utils/functions.py

@@ -13,6 +13,9 @@ def f(fname: str, farn: str, fargs: str):
     with ThreadPoolExecutor() as executor:
         running_tasks: List[Future] = []
         for arn in lambdas_arn:
+            # Sleep 0.5, 1, 1.5, ... seconds between each invocation. This way
+            # we can guarantee that lambdas are executed in parallel, but they are
+            # called in the same "order" as they are passed in.
             time.sleep(0.5 * len(running_tasks))
             running_tasks.append(executor.submit(f, function_name, arn, arguments))