Merge pull request #1573 from talyz/mapping-types

ImmutableValidatedObject: Support nested Mapping types

Author: roberth

nixops/util.py

@@ -17,8 +17,9 @@
 import re
 import typing
 import typeguard # type: ignore
-import inspect
 import shlex
+import collections.abc
+from inspect import isclass
 from typing import (
  Callable,
  List,
@@ -149,21 +150,33 @@ def _transform_value(key: Any, value: Any) -> Any:
  if not ann:
  return value
 
- if inspect.isclass(ann) and issubclass(ann, ImmutableValidatedObject):
+ if isclass(ann) and issubclass(ann, ImmutableValidatedObject):
  value = ann(**value)
 
- # Support Sequence[ImmutableValidatedObject]
- if isinstance(value, tuple) and not isinstance(ann, str):
- new_value = []
- for v in value:
- for subann in ann.__args__: # type: ignore
- if inspect.isclass(subann) and issubclass(
- subann, ImmutableValidatedObject
- ):
- new_value.append(subann(**v))
- else:
- new_value.append(v)
- value = tuple(new_value)
+ # Support containers of ImmutableValidatedObjects
+ match typing.get_origin(ann):
+
+ case collections.abc.Sequence:
+ sequence: List = []
+ for v in value:
+ for subann in typing.get_args(ann):
+ if isclass(subann) and issubclass(
+ subann, ImmutableValidatedObject
+ ):
+ sequence.append(subann(**v))
+ else:
+ sequence.append(v)
+ value = tuple(sequence)
+
+ case collections.abc.Mapping:
+ _, value_ann = typing.get_args(ann)
+ if isclass(value_ann) and issubclass(
+ value_ann, ImmutableValidatedObject
+ ):
+ mapping: Dict = {}
+ for k, v in value.items():
+ mapping[k] = value_ann(**v)
+ value = mapping
 
  typeguard.check_type(value, ann)
 

tests/unit/test_util.py

@@ -1,4 +1,4 @@
-from typing import Any, Sequence
+from typing import Any, Sequence, Mapping
 import json
 from nixops.logger import Logger
 from io import StringIO
@@ -121,4 +121,14 @@ class B(A):
  class WithSequence(util.ImmutableValidatedObject):
  subs: Sequence[SubResource]
 
- WithSequence(subs=[SubResource(x=1), SubResource(x=2)])
+ seq = WithSequence(subs=[{"x": 1}, {"x": 2}])
+ for i in seq.subs:
+ self.assertIsInstance(i, SubResource)
+
+ # Test Mapping[str, ImmutableValidatedObject]
+ class WithMapping(util.ImmutableValidatedObject):
+ mapping: Mapping[str, SubResource]
+
+ mapped = WithMapping(mapping={"aaa": {"x": 1}, "bbb": {"x": 2}})
+ for _, v in mapped.mapping.items():
+ self.assertIsInstance(v, SubResource)