add use_enum_values to config (#127)

* add `use_enum_values` to config

* docs and history

HISTORY.rst

@@ -9,7 +9,8 @@ v0.7.0 (2018-02-06)
 * add ``create_model`` method #113 #125
 * **breaking change**: rename ``.config`` to ``.__config__`` on a model
 * **breaking change**: remove deprecated ``.values()`` on a model, use ``.dict()`` instead
-* remove use of `OrderedDict` and use simple dict #126
+* remove use of ``OrderedDict`` and use simple dict #126
+* add ``Config.use_enum_values`` #127
 
 v0.6.4 (2018-02-01)
 ...................

docs/index.rst

@@ -226,6 +226,8 @@ Options:
 :ignore_extra: whether to ignore any extra values in input data (default: ``True``)
 :allow_extra: whether or not too allow (and include on the model) any extra values in input data (default: ``False``)
 :allow_mutation: whether or not models are faux-immutable, e.g. __setattr__ fails (default: ``True``)
+:use_enum_values: whether to populate models with the ``value`` property of enums,
+    rather than the raw enum - useful if you want to serialise ``model.dict()`` later (default: ``False``)
 :fields: extra information on each field, currently just "alias" is allowed (default: ``None``)
 :validate_assignment: whether to perform validation on assignment to attributes or not (default: ``False``)
 

pydantic/main.py

@@ -21,6 +21,7 @@ class BaseConfig:
     ignore_extra = True
     allow_extra = False
     allow_mutation = True
+    use_enum_values = False
     fields = {}
     validate_assignment = False
 

pydantic/validators.py

@@ -103,8 +103,9 @@ def set_validator(v) -> set:
     return set(v)
 
 
-def enum_validator(v, field, **kwargs) -> Enum:
-    return field.type_(v)
+def enum_validator(v, field, config, **kwargs) -> Enum:
+    enum_v = field.type_(v)
+    return enum_v.value if config.use_enum_values else enum_v
 
 
 def uuid_validator(v) -> UUID:

tests/test_main.py

@@ -1,4 +1,5 @@
 import json
+from enum import Enum
 from typing import Any
 
 import pytest
@@ -369,3 +370,29 @@ def test_validating_assignment_fail():
     assert """error validating input
 b:
   length less than minimum allowed: 1 (error_type=ValueError track=ConstrainedStrValue)""" == str(exc_info.value)
+
+
+def test_enum_values():
+    FooEnum = Enum('FooEnum', {'foo': 'foo', 'bar': 'bar'})
+
+    class Model(BaseModel):
+        foo: FooEnum = None
+
+        class Config:
+            use_enum_values = True
+
+    m = Model(foo='foo')
+    # this is the actual value, so has not "values" field
+    assert not isinstance(m.foo, FooEnum)
+    assert m.foo == 'foo'
+
+
+def test_enum_raw():
+    FooEnum = Enum('FooEnum', {'foo': 'foo', 'bar': 'bar'})
+
+    class Model(BaseModel):
+        foo: FooEnum = None
+    m = Model(foo='foo')
+    assert isinstance(m.foo, FooEnum)
+    assert m.foo != 'foo'
+    assert m.foo.value == 'foo'