From 85b9281689f0b6b3ea0f7184cafd6b78637830aa Mon Sep 17 00:00:00 2001
From: Chris Targett <chris@xlevus.net>
Date: Sun, 16 Apr 2017 13:41:13 +0100
Subject: [PATCH] Added support for schemaless/empty {'type': 'object'} fields.

---
 jsonmodels/builders.py                  |  2 ++
 jsonmodels/fields.py                    |  9 ++++++++-
 tests/fixtures/schema_empty_object.json | 24 ++++++++++++++++++++++++
 tests/test_jsonmodels.py                | 18 ++++++++++++++++++
 tests/test_schema.py                    | 16 ++++++++++++++++
 5 files changed, 68 insertions(+), 1 deletion(-)
 create mode 100644 tests/fixtures/schema_empty_object.json

diff --git a/jsonmodels/builders.py b/jsonmodels/builders.py
index 7274e11..151d018 100644
--- a/jsonmodels/builders.py
+++ b/jsonmodels/builders.py
@@ -142,6 +142,8 @@ def build(self):
             return {'type': 'number'}
         elif issubclass(self.type, float):
             return {'type': 'number'}
+        elif self.type == dict:
+            return {'type': 'object'}
 
         raise errors.FieldNotSupported(
             "Can't specify value schema!", self.type
diff --git a/jsonmodels/fields.py b/jsonmodels/fields.py
index c478495..b38b655 100644
--- a/jsonmodels/fields.py
+++ b/jsonmodels/fields.py
@@ -304,7 +304,14 @@ def _get_embed_type(self):
         return self.types[0]
 
     def to_struct(self, value):
-        return value.to_struct()
+        try:
+            return value.to_struct()
+        except AttributeError:
+            # Only when we specify `dict` as a type should
+            # we return the raw value.
+            if dict not in self.types:
+                raise
+            return value.copy()
 
 
 class _LazyType(object):
diff --git a/tests/fixtures/schema_empty_object.json b/tests/fixtures/schema_empty_object.json
new file mode 100644
index 0000000..4ba9158
--- /dev/null
+++ b/tests/fixtures/schema_empty_object.json
@@ -0,0 +1,24 @@
+{
+    "additionalProperties": false,
+    "definitions": {
+        "tests_test_schema_structured": {
+            "additionalProperties": false,
+            "properties": {
+                "key": {"type": "string"},
+                "value": {"type": "string"}
+            },
+            "type": "object"
+        }
+    },
+    "properties": {
+        "arbitrary": {"type": "object"},
+        "structured": "#/definitions/tests_test_schema_structured",
+        "type_choices": {
+            "oneOf": [
+                "#/definitions/tests_test_schema_structured",
+                {"type": "object"}
+            ]
+        }
+    },
+    "type": "object"
+}
diff --git a/tests/test_jsonmodels.py b/tests/test_jsonmodels.py
index 2d8ea61..df9db65 100644
--- a/tests/test_jsonmodels.py
+++ b/tests/test_jsonmodels.py
@@ -574,3 +574,21 @@ class Model(models.Base):
     assert Model(age=1) == Model(age=1)
     assert Model(age=1) != Model(age=2)
     assert Model(name='William', age=1) != Model(age=1)
+
+
+def test_empty_object():
+    class Model(models.Base):
+        data = fields.EmbeddedField(dict)
+
+    inst = Model(data={'wiz': 'boing'})
+
+    assert inst.data == {'wiz': 'boing'}
+
+
+def test_empty_object_to_struct():
+    class Model(models.Base):
+        data = fields.EmbeddedField(dict)
+
+    inst = Model(data={'wiz': 'boing'})
+
+    assert inst.to_struct() == {'data': {'wiz': 'boing'}}
diff --git a/tests/test_schema.py b/tests/test_schema.py
index 9efaf77..548519a 100644
--- a/tests/test_schema.py
+++ b/tests/test_schema.py
@@ -371,3 +371,19 @@ class Person(models.Base):
 
     with pytest.raises(errors.FieldNotSupported):
         Person.to_json_schema()
+
+
+def test_schema_empty_object():
+    class Structured(models.Base):
+        key = fields.StringField()
+        value = fields.StringField()
+
+    class DataContainer(models.Base):
+        arbitrary = fields.EmbeddedField(dict)
+        structured = fields.EmbeddedField(Structured)
+        type_choices = fields.EmbeddedField([Structured, dict])
+
+    schema = DataContainer.to_json_schema()
+
+    pattern = get_fixture('schema_empty_object.json')
+    assert compare_schemas(pattern, schema)