Preserve kwargs for json.dumps()

django_pydantic_field/base.py

@@ -95,11 +95,20 @@ def prepare_schema(schema: "ModelType", owner: t.Any = None) -> None:
 
 
 def extract_export_kwargs(ctx: dict, extractor=dict.get) -> t.Dict[str, t.Any]:
+    """ Extract ``BaseModel.json()`` kwargs from ctx for field deconstruction/reconstruction."""
+
     export_ctx = dict(
         exclude_defaults=extractor(ctx, "exclude_defaults", None),
         exclude_none=extractor(ctx, "exclude_none", None),
         exclude_unset=extractor(ctx, "exclude_unset", None),
         by_alias=extractor(ctx, "by_alias", None),
+
+        # extract json.dumps(...) kwargs, see:  https://docs.pydantic.dev/1.10/usage/exporting_models/#modeljson
+        skipkeys=extractor(ctx, "skipkeys", None),
+        indent=extractor(ctx, "indent", None),
+        separators=extractor(ctx, "separators", None),
+        allow_nan=extractor(ctx, "allow_nan", None),
+        sort_keys=extractor(ctx, "sort_keys", None),
     )
     include_fields = extractor(ctx, "include", None)
     if include_fields is not None:

tests/test_form_field.py

@@ -20,12 +20,31 @@ def test_form_schema_field():
     cleaned_data = field.clean('{"stub_str": "abc", "stub_list": ["1970-01-01"]}')
     assert cleaned_data == InnerSchema.parse_obj({"stub_str": "abc", "stub_list": ["1970-01-01"]})
 
+
 def test_empty_form_values():
     field = forms.SchemaField(InnerSchema, required=False)
     assert field.clean("") is None
     assert field.clean(None) is None
 
 
+def test_prepare_value():
+    field = forms.SchemaField(InnerSchema, required=False)
+    expected = '{"stub_str": "abc", "stub_int": 1, "stub_list": ["1970-01-01"]}'
+    assert expected == field.prepare_value({"stub_str": "abc", "stub_list": ["1970-01-01"]})
+
+
+def test_prepare_value_export_params():
+    field = forms.SchemaField(InnerSchema, required=False, indent=2, sort_keys=True, separators=('', ' > '))
+    expected = """{
+  "stub_int" > 1
+  "stub_list" > [
+    "1970-01-01"
+  ]
+  "stub_str" > "abc"
+}"""
+    assert expected == field.prepare_value({"stub_str": "abc", "stub_list": ["1970-01-01"]})
+
+
 def test_empty_required_raises():
     field = forms.SchemaField(InnerSchema)
     with pytest.raises(ValidationError) as e:
@@ -83,6 +102,9 @@ def test_forwardref_model_formfield():
     {"exclude_defaults": True},
     {"exclude_none": True},
     {"by_alias": True},
+    {"indent": 4},
+    {"separators": (',', ': ')},
+    {"sort_keys": True},
 ])
 def test_form_field_export_kwargs(export_kwargs):
     field = forms.SchemaField(InnerSchema, required=False, **export_kwargs)