Chef - Don't use metadata for hash generation in naming convention

examples/chef/BUILD.gn

@@ -27,7 +27,7 @@ pw_python_package("chef") {
 
  inputs = [
  "sample_app_util/test_files/sample_zap_file.zap",
- "sample_app_util/test_files/sample_zap_file_hashmeta.yaml",
+ "sample_app_util/test_files/sample_zap_file_meta.yaml",
  ]
 
  sources = [

examples/chef/chef.py

@@ -161,7 +161,7 @@ def bundle(platform: str, device_name: str) -> None:
  dest_item = os.path.join(_CD_STAGING_DIR, matter_file)
  shutil.copy(src_item, dest_item)
  flush_print(f"Generating metadata for {device_name}")
- metadata_file = zap_file_parser.generate_hash_metadata_file(zap_file)
+ metadata_file = zap_file_parser.generate_metadata_file(zap_file)
  metadata_dest = os.path.join(_CD_STAGING_DIR,
  os.path.basename(metadata_file))
  shutil.copy(metadata_file, metadata_dest)

examples/chef/dockerfile

@@ -11,7 +11,7 @@ RUN apt-get update && \
 COPY out/${DEVICE_NAME} /chef_device
 COPY out/${DEVICE_NAME}.map /chef_device.map
 COPY out/${DEVICE_NAME}.matter /chef_device.matter
-COPY out/${DEVICE_NAME}_hashmeta.yaml /chef_device_hashmeta.yaml
+COPY out/${DEVICE_NAME}_meta.yaml /chef_device_meta.yaml
 
 ENV DBUS_SYSTEM_BUS_ADDRESS="unix:path=/var/run/dbus/system_bus_socket"
 

examples/chef/sample_app_util/README.md

@@ -33,7 +33,10 @@ should rarely happen.
 
 Sample apps should be named by concatenating the name of all endpoints in the
 order of their index. Endpoint names are separated by underscores (`_`) and a 10
-character hash[^hash_note] of the sample app metadata is appended to the end.
+character hash[^hash_note] which is randomly generated.
+
+The naming convention tool should be used for every newly created app. The name
+should only need to be updated if the endpoints of the app are changed.
 
 Valid sample app names conform to the following format:
 
@@ -62,16 +65,12 @@ bridgednode_temperaturesensor_onofflight_onoffpluginunit_MI9DSdkH8H
 
 [^hash_note]:
 
- The 10 character hash is a base64 encoding of the md5 hash generated by
- digesting the JSON string encoding of the metadata information. The code for
- generating the hash can be found in `generate_hash` in
- [zap_file_parser](zap_file_parser.py) There are some notable details
- here: 1) The full base64 encoded hash is 16 characters, but only 10 are
- used. This still gives us a sufficiently low probability of collision (~1.2
- x 10^-8). 2) `_` and `-` are replaced in the base64 encoding because they
- have other uses in the naming. 3) Platform specific information is omitted
- from the hash. E.g. the networking_commissioning cluster is excluded. This
- is to make the hashes platform agnostic.
+ The 10 character hash used to be generated by consuming the JSON encoded
+ metadata. This is no longer the case. It was found that the hash encoding
+ only served to differentiate one app from another (the initial goal) and
+ there was little value in tying the generated hash to the config data
+ because there wasn't a use case for decoding it as long as the config file
+ was packaged with the generated app.
 
 ### Sample App Build Naming Convention
 
@@ -139,13 +138,9 @@ The metadata files have a structure as follows:
 ```
 
 For an example, see
-[sample_zap_file_hashmeta.yaml](test_files/sample_zap_file_hashmeta.yaml) which
+[sample_zap_file_meta.yaml](test_files/sample_zap_file_meta.yaml) which
 was generated from [sample_zap_file.zap](test_files/sample_zap_file.zap).
 
-Note that it is more readable in `yaml` format. Since hashes are generated from
-the metadata info, additional conventions are needed to ensure consistency for
-the metadata structure.
-
 The following conventions are used:
 
 - All lists are sorted alphabetically.

examples/chef/sample_app_util/sample_app_util.py

@@ -32,8 +32,8 @@ def zap_cmd_handler(args: argparse.Namespace) -> None:
  output_path = os.path.join(dirpath, f"{name}.zap")
  shutil.move(zap_file_path, output_path)
  print(f"Renamed from: {zap_file_path} to {output_path}")
- elif args.generate_hash_metadata:
- created_file = zap_file_parser.generate_hash_metadata_file(zap_file_path)
+ elif args.generate_metadata:
+ created_file = zap_file_parser.generate_metadata_file(zap_file_path)
  print(f"Created {created_file}")
 
 
@@ -53,10 +53,9 @@ def zap_cmd_handler(args: argparse.Namespace) -> None:
 )
 
 zap_cmd_parser.add_argument(
- "--generate-hash-metadata", action="store_true",
+ "--generate-metadata", action="store_true",
  help=(
- "Generate the hash metadata file which provide information about what was included in "
- "the hash digest.")
+ "Generate the metadata file which provides summary information about the app.")
 )
 
 zap_cmd_group.add_argument(

examples/chef/sample_app_util/test_zap_file_parser.py

@@ -8,6 +8,8 @@
 import shutil
 import tempfile
 import unittest
+from unittest import mock
+import uuid
 
 import zap_file_parser
 
@@ -20,20 +22,21 @@
 
 _HERE = os.path.abspath(os.path.dirname(__file__))
 _TEST_FILE = os.path.join(_HERE, "test_files", "sample_zap_file.zap")
-_TEST_METADATA = os.path.join(_HERE, "test_files", "sample_zap_file_hashmeta.yaml")
+_TEST_METADATA = os.path.join(_HERE, "test_files", "sample_zap_file_meta.yaml")
 
 
 class TestZapFileParser(unittest.TestCase):
  """Testcases for zap_file_parser.py."""
 
  def test_generate_hash(self):
  """Tests generate_hash function."""
- hash_string = zap_file_parser.generate_hash(_TEST_FILE)
- self.assertEqual(hash_string, "Xir1gEfjij", "Hash is incorrectly generated.")
+ with mock.patch.object(uuid, "uuid4", return_value="Xir1gEfjij"):
+ hash_string = zap_file_parser.generate_hash()
+ self.assertEqual(hash_string, "Xir1gEfjij", "Hash is incorrectly generated.")
 
  def test_generate_metadata(self):
  """Tests generate_metadata."""
- generated_metadata = zap_file_parser.generate_hash_metadata(_TEST_FILE)
+ generated_metadata = zap_file_parser.generate_metadata(_TEST_FILE)
  with open(_TEST_METADATA) as f:
  expected_metadata = yaml.load(f.read(), Loader=yaml.FullLoader)
  self.assertEqual(
@@ -43,10 +46,10 @@ def test_generate_metadata_file(self):
  """Tests generate_metadata_file."""
  with tempfile.TemporaryDirectory(dir=os.path.dirname(_HERE)) as dir:
  zap_file = os.path.join(dir, "test_file.zap")
- hashmeta_file = os.path.join(dir, "test_file_hashmeta.yaml")
+ meta_file = os.path.join(dir, "test_file_meta.yaml")
  shutil.copy(_TEST_FILE, zap_file)
- zap_file_parser.generate_hash_metadata_file(zap_file)
- with open(hashmeta_file) as f:
+ zap_file_parser.generate_metadata_file(zap_file)
+ with open(meta_file) as f:
  generated_metadata = yaml.load(f.read(), Loader=yaml.FullLoader)
  with open(_TEST_METADATA) as f:
  expected_metadata = yaml.load(f.read(), Loader=yaml.FullLoader)
@@ -55,8 +58,9 @@ def test_generate_metadata_file(self):
 
  def test_generate_name(self):
  """Tests generate_name."""
- name = zap_file_parser.generate_name(_TEST_FILE)
- self.assertEqual(name, "rootnode_dimmablelight_Xir1gEfjij", "Name incorrectly generated.")
+ with mock.patch.object(uuid, "uuid4", return_value="Xir1gEfjij"):
+ name = zap_file_parser.generate_name(_TEST_FILE)
+ self.assertEqual(name, "rootnode_dimmablelight_Xir1gEfjij", "Name incorrectly generated.")
 
 
 if __name__ == "__main__":

examples/chef/sample_app_util/zap_file_parser.py

@@ -29,13 +29,12 @@
  available.
  - Add support for .matter files.
 """
-import base64
 import copy
-import hashlib
 import json
 import os
 import re
 from typing import Dict, List, Optional, Sequence, TypedDict, Union
+import uuid
 
 try:
  import yaml
@@ -64,19 +63,6 @@ class EndpointType(TypedDict):
  server_clusters: Dict[str, ClusterType]
 
 
-def _b64encode(input_data: bytes) -> bytes:
- """Returns urlsafe base64 encoded with padding removed."""
- return base64.urlsafe_b64encode(input_data).strip(b"=")
-
-
-def _b64decode(input_data: bytes) -> bytes:
- """Returns urlsafe base64 decoded with padding added."""
- # "=" is padding character that doesn't carry info.
- # Adding 2x "=" will handle all edge cases where there may be
- # incorrect number of bytes.
- return base64.urlsafe_b64decode(input_data + b"==")
-
-
 def _convert_metadata_name(name: str, code: Union[int, str]) -> str:
  """Converts a name for use in a metadata file - CamelCaseName/ID."""
  # Preserve camel case if it's already there
@@ -181,35 +167,13 @@ def _get_id(name):
  return name.split("/")[-1]
 
 
-def generate_hash(zap_file_path: str) -> str:
+def generate_hash() -> str:
  """Generates a hash for a zap file.
 
- Args:
- zap_file_path: Path to the zap file.
-
  Returns:
- MD5 hash of the metadata generated from the zap file.
- This is converted to base64 and then the first 10 characters are used.
+ A 10 character alphanumeric hash.
  """
- parsed = generate_hash_metadata(zap_file_path)
- # Use json.dumps to produce a consistent output for the object passed into it.
- digestible_content = _convert_metadata_to_hashable_digest(parsed)
- md5_hash = hashlib.md5(digestible_content.encode("utf-8")).digest()
- output = str(_b64encode(md5_hash), encoding="utf-8")[:10]
- # Replace "-" and "_" with "a" and "b".
- # The reason for doing this is to allow the generated name to be parsed by splitting on "_".
- # Replacing "-" makes the name easier to parse visually.
- # This increases likelihood of hash collisions, but minimally so. See module docstring.
- return output.replace("-", "a").replace("_", "b")
-
-
-def generate_hash_metadata(zap_file_path: str) -> List[Dict[str, EndpointType]]:
- """Generates metadata for hash digest consumption."""
- return generate_metadata(
- zap_file_path=zap_file_path,
- attribute_allow_list=_ATTRIBUTE_ALLOW_LIST,
- include_commands=False,
- include_platform_specific_info=False)
+ return str(uuid.uuid4())[-10:]
 
 
 def generate_metadata(
@@ -320,21 +284,21 @@ def generate_metadata(
  return return_obj
 
 
-def generate_hash_metadata_file(zap_file_path: str) -> str:
- """Generates hash metadata file for a zap file input.
+def generate_metadata_file(zap_file_path: str) -> str:
+ """Generates metadata file for a zap file.
 
  The purpose of this file is to inform the user what data was included in the hash digest.
 
  Args:
  zap_file_path: Path to the zap file to parse for generating the metadata file.
  """
- parsed = generate_hash_metadata(zap_file_path)
+ parsed = generate_metadata(zap_file_path)
  output = yaml.dump(parsed, indent=4, sort_keys=True)
 
  dirname, filename = os.path.split(zap_file_path)
 
  filename = os.path.splitext(filename)[0]
- output_file_path = os.path.join(dirname, f"{filename}_hashmeta.yaml")
+ output_file_path = os.path.join(dirname, f"{filename}_meta.yaml")
  with open(output_file_path, "w") as f:
  f.write(output)
  return output_file_path
@@ -354,5 +318,5 @@ def generate_name(zap_file_path: str) -> str:
  for endpoint in parsed:
  name = next(iter(endpoint))
  names.append(_convert_filename(name))
- hash_string = generate_hash(zap_file_path)
+ hash_string = generate_hash()
  return "_".join(names) + f"_{hash_string}"

examples/chef/setup.cfg

@@ -24,7 +24,7 @@ zip_safe = False
 [options.package_data]
 sample_app_util =
  test_files/sample_zap_file.zap
- test_files/sample_zap_file_hashmeta.yaml
+ test_files/sample_zap_file_meta.yaml
 
 [options.entry_points]
 console_scripts = chef = chef:main