Include complete platforms for FaaS environments for more reliable building

build-support/bin/generate_faas_complete_platforms.py

@@ -0,0 +1,65 @@
+# Copyright 2023 Pants project contributors (see CONTRIBUTORS.md).
+# Licensed under the Apache License, Version 2.0 (see LICENSE).
+
+from __future__ import annotations
+
+import argparse
+import json
+import subprocess
+import sys
+from pathlib import Path
+
+from pants.backend.awslambda.python.target_types import PythonAwsLambdaRuntime
+from pants.backend.python.util_rules.faas import PythonFaaSRuntimeField
+from pants.base.build_environment import get_buildroot
+
+COMMAND = "pip install pex 1>&2 && pex3 interpreter inspect --markers --tags"
+
+
+RUNTIME_FIELDS = [
+    PythonAwsLambdaRuntime,
+    # TODO: what docker images to use for GCF?
+]
+
+
+def extract_complete_platform(repo: str, tag: str) -> object:
+    image = f"{repo}:{tag}"
+    print(f"Extracting complete platform for {image}", file=sys.stderr)
+    result = subprocess.run(
+        ["docker", "run", "--entrypoint", "sh", image, "-c", COMMAND],
+        check=True,
+        stdout=subprocess.PIPE,
+    )
+    return json.loads(result.stdout)
+
+
+def run(runtime_field: type[PythonFaaSRuntimeField], python_base: Path) -> None:
+    cp_dir = python_base / runtime_field.known_runtimes_complete_platforms_module().replace(
+        ".", "/"
+    )
+    print(f"Generating for {runtime_field.__name__}, writing to {cp_dir}", file=sys.stderr)
+    for rt in runtime_field.known_runtimes:
+        cp = extract_complete_platform(runtime_field.known_runtimes_docker_repo, rt.tag)
+
+        fname = cp_dir / rt.file_name()
+        with fname.open("w") as f:
+            json.dump(cp, f, indent=2)
+
+
+def create_parser() -> argparse.ArgumentParser:
+    parser = argparse.ArgumentParser(
+        description="Generates the complete platform JSON files for AWS Lambda and GCF"
+    )
+    return parser
+
+
+def main() -> None:
+    create_parser().parse_args()
+
+    build_root = Path(get_buildroot()) / "src/python"
+    for runtime_field in RUNTIME_FIELDS:
+        run(runtime_field, build_root)
+
+
+if __name__ == "__main__":
+    main()

src/python/pants/backend/awslambda/python/BUILD

@@ -1,7 +1,10 @@
 # Copyright 2019 Pants project contributors (see CONTRIBUTORS.md).
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 
-python_sources()
+python_sources(overrides={"target_types.py": {"dependencies": [":complete_platforms"]}})
+
+# generated by build-support/bin/generate_faas_complete_platforms.py
+resources(name="complete_platforms", sources=["complete_platform_*.json"])
 
 python_tests(name="target_types_test", sources=["target_types_test.py"], timeout=120)
 python_tests(