Merge pull request #23 from color/mpcusack-lists

Add list value support to clrenv 0.2

Author: mpcusack-color

clrenv/evaluate.py

@@ -27,7 +27,6 @@
 from collections import abc
 from pathlib import Path
 from typing import (
-    Any,
     Iterable,
     Iterator,
     List,
@@ -41,15 +40,16 @@
 )
 
 from .path import environment_paths
-from .read import EnvReader, NestedMapping, PrimitiveValue
+from .read import EnvReader
+from .types import LeafValue, NestedMapping, check_valid_leaf_value
 
 logger = logging.getLogger(__name__)
 
 DEBUG_MODE = os.environ.get("CLRENV_DEBUG", "").lower() in ("true", "1")
 
 # Access to an attribute might return a primitive or if it is not a leaf node
 # another SubClrEnv.
-Value = Union[PrimitiveValue, "SubClrEnv"]
+Value = Union[LeafValue, "SubClrEnv"]
 
 
 class SubClrEnv(abc.MutableMapping):
@@ -90,10 +90,10 @@ def __getattr__(self, key: str) -> Value:
         except KeyError as e:
             raise AttributeError(str(e))
 
-    def __setitem__(self, key: str, value: PrimitiveValue):
+    def __setitem__(self, key: str, value: LeafValue):
         self._root.set_runtime_override(self._sub_key_path(key), value)
 
-    def __setattr__(self, key: str, value: PrimitiveValue):
+    def __setattr__(self, key: str, value: LeafValue):
         """Sets a runtime override as an attribute."""
         # Internal fields are prefixed with a _ and should be treated normally.
         if key.startswith("_"):
@@ -145,7 +145,7 @@ def _sub_keys(self) -> Set[str]:
                 subkeys.add(env_var.split("__")[0].lower())
         return subkeys
 
-    def _evaluate_key(self, key: str) -> Union[PrimitiveValue, Mapping, None]:
+    def _evaluate_key(self, key: str) -> Union[LeafValue, Mapping, None]:
         """Returns the stored value for the given key.
 
         There are three potential sources of data (in order of priority):
@@ -219,7 +219,7 @@ def __init__(self, paths: Optional[List[Path]] = None):
         # efficent lookup for subkeys.
         # env.a.b.c = 'd' ==> _runtime_overrides = {('a', 'b'): {'c': 'd'}}
         self._runtime_overrides: MutableMapping[
-            Tuple[str, ...], MutableMapping[str, PrimitiveValue]
+            Tuple[str, ...], MutableMapping[str, LeafValue]
         ] = {}
 
     def _make_env(self) -> NestedMapping:
@@ -230,7 +230,9 @@ def clear_runtime_overrides(self):
         """Clear all runtime overrides."""
         self._runtime_overrides.clear()
 
-    def set_runtime_override(self, key_path: Sequence[str], value: PrimitiveValue):
+    def set_runtime_override(
+        self, key_path: Union[str, Sequence[str]], value: LeafValue
+    ):
         """Sets a runtime override.
 
         Only do this in tests and ideally use unittest.mock.patch or monkeypath.setattr
@@ -239,20 +241,19 @@ def set_runtime_override(self, key_path: Sequence[str], value: PrimitiveValue):
         Notice that this method is only on the root node."""
         if not key_path:
             raise ValueError("key_path can not be empty.")
+        # No support for nested runtime overrides. Only allow primitives.
+        check_valid_leaf_value(key_path, value)
+
         if isinstance(key_path, str):
             key_path = key_path.split(".")
 
         # Check that the key already exists.
-        parent: Union[SubClrEnv, PrimitiveValue] = self
+        parent: Union[SubClrEnv, LeafValue] = self
         for name in key_path:
             assert isinstance(parent, Mapping)
             assert name in parent, f"{name, parent}"
             parent = parent[name]
 
-        # No support for nested runtime overrides. Only allow primitives.
-        if not isinstance(value, PrimitiveValue.__args__):  # type: ignore
-            raise ValueError("Env values must be one of {str, int, float, boolean}.")
-
         # Ideally we wouldn't be overriding global state like this at all, but at least
         # make it loud.
         logger.warning(f"Manually overriding env.{'.'.join(key_path)} to {value}.")

clrenv/read.py

@@ -15,22 +15,19 @@
 import os
 from collections import abc, deque
 from pathlib import Path
-from typing import Any, Deque, Iterable, Mapping, MutableMapping, Optional, Tuple, Union
+from typing import Any, Deque, Iterable, Mapping, Optional, Tuple
 
 import boto3
 from botocore.exceptions import EndpointConnectionError  # type: ignore
 
 from .deepmerge import deepmerge
 from .path import environment_paths
+from .types import MutableNestedMapping, NestedMapping, check_valid_leaf_value
 
 logger = logging.getLogger(__name__)
 
 # Types that can be read or set as values of leaf nodes.
-PrimitiveValue = Union[bool, int, float, str]
-NestedMapping = Mapping[str, Union[PrimitiveValue, Mapping[str, Any]]]
-MutableNestedMapping = MutableMapping[
-    str, Union[PrimitiveValue, MutableMapping[str, Any]]
-]
+
 
 # Flag to prevent clrenv from throwing errors
 #  if it cannot connect to the Parameter Store API.
@@ -106,6 +103,8 @@ def read(self) -> NestedMapping:
                     mapping[key] = ""  # type: ignore
                 elif isinstance(value, str):
                     mapping[key] = self.postprocess_str(value)
+                else:
+                    check_valid_leaf_value(key_prefix + key, value)
 
         return result
 

clrenv/tests/__init__.py

@@ -179,6 +179,6 @@ def test_env_var(monkeypatch, default_env):
 
 def test_underscored_keys(default_env):
     with pytest.raises(KeyError):
-        default_env["__env"]
+        default_env["__env"]  # pylint: disable=pointless-statement
     with pytest.raises(AttributeError):
         getattr(default_env.__unknown)

clrenv/tests/test_evaluate.py

@@ -0,0 +1,26 @@
+from typing import Any, List, Mapping, MutableMapping, Union
+
+"""Defines type annotations for use in clrenv.
+
+Ideally we would only allow str leaf values so that they can be migrated to an env
+var based system. For now we must supports more complex values.
+"""
+
+# Type that can be read or set as values of leaf nodes.
+LeafValue = Union[bool, int, float, str, List[Union[bool, int, float, str]]]
+# Type of a non leaf node.
+NestedMapping = Mapping[str, Union[LeafValue, Mapping[str, Any]]]
+MutableNestedMapping = MutableMapping[str, Union[LeafValue, MutableMapping[str, Any]]]
+
+PRIMITIVE_TYPES = (bool, int, float, str)
+
+
+def check_valid_leaf_value(key: Any, value: Any) -> None:
+    """Raises a ValueError is the value is not a valid type.
+
+    key is only used for the error message."""
+    if isinstance(value, PRIMITIVE_TYPES):
+        return
+    if isinstance(value, list) and all(isinstance(_, PRIMITIVE_TYPES) for _ in value):
+        return
+    raise ValueError(f"Non primitive value type: {key}={value}")

clrenv/types.py

@@ -5,7 +5,7 @@
 
 setup(
     name="clrenv",
-    version="0.2.0",
+    version="0.2.1",
     description="A tool to give easy access to environment yaml file to python.",
     author="Color",
     author_email="[email protected]",