Merge pull request #1 from gridsmartercities/parse_lists

Added list parsing, brought library more in line with other Grid libraries

Author: jamsidedown

.gitignore

@@ -114,4 +114,4 @@ venv.bak/
 */.DS_Store
 
 # vscode
-.vscode
+.vscode

CONTRIBUTING.md

@@ -24,8 +24,24 @@ aws_dynamodb_parser/utils.py      29      0     24      0   100%
 We require all code to adhere to our linting style as defined in [pylintrc](https://github.com/gridsmartercities/aws-dynamodb-parser/blob/master/pylintrc). We use [prospector](https://pypi.org/project/prospector/) to run linting checks.
 ```sh
 $ prospector
+Check Information
+=================
+         Started: 2020-10-01 17:55:32.697915
+        Finished: 2020-10-01 17:55:33.725397
+      Time Taken: 1.03 seconds
+       Formatter: text
+        Profiles: .prospector.yaml, full_pep8, no_doc_warnings, strictness_veryhigh, no_member_warnings
+      Strictness: from profile
+  Libraries Used:
+       Tools Run: dodgy, mccabe, pep8, profile-validator, pyflakes, pylint
+  Messages Found: 0
+ External Config: pylint: /Users/rob/Documents/code/grid/aws-dynamodb-parser/pylintrc
+```
 
-# clean prospector output will be added once the repo is cleaned up
+We require code to have correct type hinting using [Mypy](http://www.mypy-lang.org/) to check type hints.
+```sh
+$ ./tools/mypy.sh
+Success: no issues found in 2 source files
 ```
 
 And lastly that [Bandit](https://pypi.org/project/bandit/) security checks pass

aws_dynamodb_parser/__init__.py

@@ -1 +1,3 @@
-from aws_dynamodb_parser.utils import *  # noqa
+__all__ = ["parse"]
+
+from .utils import parse

aws_dynamodb_parser/utils.py

@@ -1,44 +1,52 @@
 import base64
+from typing import Any, Union
 
 
-def parse(dynamodb_object):
-    for key in dynamodb_object.keys():
-        dynamodb_object[key] = parse_pair(dynamodb_object[key])
-    return dynamodb_object
+def parse(dynamodb_object: Union[dict, list]) -> Union[dict, list]:
+    if isinstance(dynamodb_object, list):
+        return [parse(obj) for obj in dynamodb_object]
 
+    return {key: _parse_property(value) for key, value in dynamodb_object.items()}
 
-def parse_pair(type_value_pair):  # noqa: pylint - too-many-return-statements
-    data_type = list(type_value_pair.keys())[0]
 
-    if data_type in ('S', 'SS', 'BOOL'):
-        return type_value_pair[data_type]
+# pylint:disable=too-many-return-statements
+def _parse_property(prop: dict) -> Any:
+    data_type = next(iter(prop))
+    value = prop.get(data_type, [])
 
-    if data_type == 'N':
-        return to_num(type_value_pair[data_type])
+    if data_type in {"S", "SS", "BOOL"}:
+        return value
 
-    if data_type == 'NS':
-        return [to_num(data) for data in type_value_pair[data_type]]
+    if data_type == "N":
+        return _to_num(value)
 
-    if data_type == 'B':
-        return base64.decodebytes(bytes(type_value_pair[data_type], 'utf-8'))
+    if data_type == "NS":
+        return [_to_num(item) for item in value]
 
-    if data_type == 'BS':
-        return [base64.decodebytes(bytes(data, 'utf-8')) for data in type_value_pair[data_type]]
+    if data_type == "B":
+        return _to_bytes(value)
 
-    if data_type == 'M':
-        return parse(type_value_pair[data_type])
+    if data_type == "BS":
+        return [_to_bytes(item) for item in value]
 
-    if data_type == 'L':
-        return [parse_pair(item) for item in type_value_pair[data_type]]
+    if data_type == "M":
+        return parse(value)
 
-    if data_type == 'NULL' and type_value_pair[data_type]:
+    if data_type == "L":
+        return [_parse_property(item) for item in value]
+
+    if data_type == "NULL" and value:
         return None
 
-    raise TypeError('Unknown DynamoDB data type \'%s\' with value \'%s\'' % (data_type, type_value_pair[data_type]))
+    raise TypeError("Unknown DynamoDB data type '%s' with value '%s'" % (data_type, value))
 
 
-def to_num(number):
+def _to_num(value: Any) -> Union[float, int]:
     try:
-        return int(number)
+        return int(value)
     except ValueError:
-        return float(number)
+        return float(value)
+
+
+def _to_bytes(value: Any) -> bytes:
+    return base64.decodebytes(bytes(value, "utf-8"))

requirements.txt

@@ -1,4 +1,5 @@
 coverage
 prospector
 bandit
-pylint-quotes
+pylint-quotes
+mypy

setup.py

@@ -1,24 +1,26 @@
 from setuptools import setup, find_packages
 
-LONG_DESCRIPTION = open('README.md').read()
+LONG_DESCRIPTION = open("README.md").read()
 
-setup(name='aws-dynamodb-parser',
-      version='0.1',
-      description='AWS DynamoDB utility for parsing DynamoDB responses',
-      long_description=LONG_DESCRIPTION,
-      long_description_content_type="text/markdown",
-      url='https://github.com/gridsmartercities/aws-dynamodb-parser',
-      author='Grid Smarter Cities',
-      author_email='[email protected]',
-      license='MIT',
-      classifiers=['Intended Audience :: Developers',
-                   'Development Status :: 3 - Alpha',
-                   'Programming Language :: Python :: 3',
-                   'License :: OSI Approved :: MIT License',
-                   'Operating System :: OS Independent',
-                   'Natural Language :: English'
-                   ],
-      keywords='aws lambda decorator',
-      packages=find_packages(exclude=('tests')),
-      zip_safe=False
-      )
+setup(
+    name="aws-dynamodb-parser",
+    version="0.1.2",
+    description="AWS DynamoDB utility for parsing DynamoDB responses",
+    long_description=LONG_DESCRIPTION,
+    long_description_content_type="text/markdown",
+    url="https://github.com/gridsmartercities/aws-dynamodb-parser",
+    author="Grid Smarter Cities",
+    author_email="[email protected]",
+    license="MIT",
+    classifiers=[
+        "Intended Audience :: Developers",
+        "Development Status :: 3 - Alpha",
+        "Programming Language :: Python :: 3",
+        "License :: OSI Approved :: MIT License",
+        "Operating System :: OS Independent",
+        "Natural Language :: English"
+    ],
+    keywords="aws lambda decorator",
+    packages=find_packages(exclude=("tests")),
+    zip_safe=False
+)