Add a method for getting serializer field name (OpenAPI) (#7493)

* Add a method for getting serializer field name

* Add docs and test

Co-authored-by: Tom Christie <tom@tomchristie.com>

rest_framework/schemas/openapi.py

@@ -523,7 +523,7 @@ class AutoSchema(ViewInspector):
                 continue
 
             if field.required:
-                required.append(field.field_name)
+                required.append(self.get_field_name(field))
 
             schema = self.map_field(field)
             if field.read_only:
@@ -538,7 +538,7 @@ class AutoSchema(ViewInspector):
                 schema['description'] = str(field.help_text)
             self.map_field_validators(field, schema)
 
-            properties[field.field_name] = schema
+            properties[self.get_field_name(field)] = schema
 
         result = {
             'type': 'object',
@@ -589,6 +589,13 @@ class AutoSchema(ViewInspector):
                     schema['maximum'] = int(digits * '9') + 1
                     schema['minimum'] = -schema['maximum']
 
+    def get_field_name(self, field):
+        """
+        Override this method if you want to change schema field name.
+        For example, convert snake_case field name to camelCase.
+        """
+        return field.field_name
+
     def get_paginator(self):
         pagination_class = getattr(self.view, 'pagination_class', None)
         if pagination_class:

tests/schemas/test_openapi.py

@@ -111,6 +111,20 @@ class TestFieldMapping(TestCase):
         assert data['properties']['default_false']['default'] is False, "default must be false"
         assert 'default' not in data['properties']['without_default'], "default must not be defined"
 
+    def test_custom_field_name(self):
+        class CustomSchema(AutoSchema):
+            def get_field_name(self, field):
+                return 'custom_' + field.field_name
+
+        class Serializer(serializers.Serializer):
+            text_field = serializers.CharField()
+
+        inspector = CustomSchema()
+
+        data = inspector.map_serializer(Serializer())
+        assert 'custom_text_field' in data['properties']
+        assert 'text_field' not in data['properties']
+
     def test_nullable_fields(self):
         class Model(models.Model):
             rw_field = models.CharField(null=True)