feat: custom django path's param convert type tfranzel#502

drf_spectacular/plumbing.py

@@ -21,6 +21,7 @@
     ReverseOneToOneDescriptor,
 )
 from django.db.models.fields.reverse_related import ForeignObjectRel
+from django.urls.converters import get_converter as django_get_converter
 from django.urls.resolvers import (  # type: ignore
     _PATH_PARAMETER_COMPONENT_RE, RegexPattern, Resolver404, RoutePattern, URLPattern, URLResolver,
     get_resolver,
@@ -33,7 +34,7 @@
 from rest_framework.utils.mediatypes import _MediaType
 from uritemplate import URITemplate
 
-from drf_spectacular.drainage import error, warn
+from drf_spectacular.drainage import error, warn, has_override, get_override
 from drf_spectacular.settings import spectacular_settings
 from drf_spectacular.types import (
     DJANGO_PATH_CONVERTER_MAPPING, OPENAPI_TYPE_MAPPING, PYTHON_TYPE_MAPPING, OpenApiTypes,
@@ -680,13 +681,34 @@ def resolve_regex_path_parameter(path_regex, variable, available_formats):
         if api_settings.SCHEMA_COERCE_PATH_PK and parameter == 'pk':
             parameter = 'id'
 
-        if parameter == variable and converter in DJANGO_PATH_CONVERTER_MAPPING:
-            return build_parameter_type(
-                name=parameter,
-                schema=build_basic_type(DJANGO_PATH_CONVERTER_MAPPING[converter]),
-                location=OpenApiParameter.PATH,
-                enum=enum_values,
-            )
+        if converter and parameter == variable:
+            if converter in DJANGO_PATH_CONVERTER_MAPPING:
+                return build_parameter_type(
+                    name=parameter,
+                    schema=build_basic_type(DJANGO_PATH_CONVERTER_MAPPING[converter]),
+                    location=OpenApiParameter.PATH,
+                    enum=enum_values,
+                )
+            else:
+                django_converter = django_get_converter(converter)
+                if django_converter:
+                    converter_schema = None
+                    converter_regex = getattr(django_converter, 'regex')
+                    if has_override(django_converter, 'field'):
+                        annotation = get_override(django_converter, 'field')
+                        converter_schema = build_basic_type(annotation) if is_basic_type(annotation) else annotation
+                    elif converter_regex:
+                        converter_schema = {
+                            'type': 'string',
+                            'pattern': converter_regex
+                        }
+                    if converter_schema:
+                        return build_parameter_type(
+                            name=parameter,
+                            schema=converter_schema,
+                            location=OpenApiParameter.PATH,
+                            enum=enum_values,
+                        )
 
     return None
 

tests/test_regressions.py

@@ -545,6 +545,51 @@ def pi(request, foo):
     assert parameter['schema']['type'] == 'integer'
 
 
+def test_regex_path_parameter_discovery_with_custom_converter(no_warnings):
+    @extend_schema(responses=OpenApiTypes.FLOAT)
+    @api_view(['GET'])
+    def pi(request, foo):
+        pass  # pragma: no cover
+
+    @extend_schema_field(OpenApiTypes.INT)
+    class CustomNumberConverter:
+        regex = '\\d+'
+
+        def to_python(self, value):
+            return int(value)
+
+        def to_url(self, value):
+            return '%d' % value
+
+    from django.urls import register_converter
+    register_converter(CustomNumberConverter, 'number')
+
+    urlpatterns = [re_path(r'^/pi/<number:precision>', pi)]
+    schema = generate_schema(None, patterns=urlpatterns)
+    parameter = schema['paths']['/pi/{precision}']['get']['parameters'][0]
+    assert parameter['name'] == 'precision'
+    assert parameter['in'] == 'path'
+    assert parameter['schema']['type'] == 'integer'
+
+    class CustomDateConverter:
+        regex = '\\d{4}-\\d{2}-\\d{2}'
+
+        def to_python(self, value):
+            return int(value)
+
+        def to_url(self, value):
+            return '%d' % value
+
+    register_converter(CustomDateConverter, 'date')
+    urlpatterns = [re_path(r'^/pi/<date:from_date>', pi)]
+    schema = generate_schema(None, patterns=urlpatterns)
+    parameter = schema['paths']['/pi/{from_date}']['get']['parameters'][0]
+    assert parameter['name'] == 'from_date'
+    assert parameter['in'] == 'path'
+    assert parameter['schema']['type'] == 'string'
+    assert parameter['schema']['pattern'] == '\\d{4}-\\d{2}-\\d{2}'
+
+
 def test_lib_serializer_naming_collision_resolution(no_warnings):
     """ parity test in tests.test_warnings.test_serializer_name_reuse """
     def x_lib1():