fix chaotic-openapi: inproper serialization for single body requests

chaotic-openapi/chaotic_openapi/back/cpp/client/templates/requests.application.multipart.formdata.jinja

@@ -2,7 +2,7 @@
   const auto &data = {{ request }};
   USERVER_NAMESPACE::clients::http::Form form;
 
-  {% for field_name, field in body.schema.fields.items() %}
+  {% for field_name, field in body.fields().items() %}
       {% if field.required %}
         form.AddContent("{{ field_name }}", USERVER_NAMESPACE::chaotic::openapi::PrimitiveToString(data.{{ field_name }}));
       {% else %}

chaotic-openapi/chaotic_openapi/back/cpp/client/templates/requests.application.octet.stream.jinja

@@ -1,5 +1,8 @@
-{% macro serialize(request, http_request) %}
-  {{ http_request }}.data({{ request }}.data);
+{# An operation with a single content type stores the body as a bare std::string,
+   while multiple content types are wrapped into distinct structs (see define_body_cpp_name)
+   to make the std::variant alternatives unambiguous. #}
+{% macro serialize(request, http_request, wrapped) %}
+  {{ http_request }}.data({{ request }}{% if wrapped %}.data{% endif %});
 {% endmacro %}
 
 

chaotic-openapi/chaotic_openapi/back/cpp/client/templates/requests.application.xwwwformurlencoded.jinja

@@ -2,7 +2,7 @@
   const auto &data = {{ request }};
   std::unordered_map<std::string, std::string> map;
 
-  {% for field_name, field in body.schema.fields.items() %}
+  {% for field_name, field in body.fields().items() %}
       {% if field.required %}
         map["{{ field_name }}"] = USERVER_NAMESPACE::chaotic::openapi::PrimitiveToString(data.{{ field_name }});
       {% else %}

chaotic-openapi/chaotic_openapi/back/cpp/client/templates/requests.cpp.jinja

@@ -17,6 +17,21 @@ namespace {{ namespace }} {
 
 namespace openapi = USERVER_NAMESPACE::chaotic::openapi;
 
+{% macro serialize_request_single_body(body, body_obj, http_request, wrapped) %}
+    {% if body.content_type != 'multipart/form-data' %}
+    sink.SetHeader(USERVER_NAMESPACE::http::headers::kContentType, "{{ body.content_type }}");
+    {% endif %}
+    {% if body.content_type == 'application/json' %}
+        {{ application_json.serialize(body_obj, http_request) }}
+    {% elif body.content_type == 'multipart/form-data' %}
+        {{ application_multipartformdata.serialize(body, body_obj, http_request) }}
+    {% elif body.content_type == 'application/x-www-form-urlencoded' %}
+        {{ application_xwwwformurlencoded.serialize(body, body_obj, http_request) }}
+    {% else %}
+        {{ application_octetstream.serialize(body_obj, http_request, wrapped=wrapped) }}
+    {% endif %}
+{% endmacro %}
+
 {% for op in operations %}
   {% if op.client_generate %}
       namespace {{ op.cpp_namespace() }} {
@@ -66,26 +81,13 @@ void SerializeRequest(const Request& request, const std::string& base_url, USERV
 
   {# body #}
   {% if len(op.request_bodies) == 1 %}
-    http_request.data(ToString(USERVER_NAMESPACE::formats::json::ValueBuilder(request.body).ExtractValue()));
+    {{ serialize_request_single_body(op.request_bodies[0], "request.body", "http_request", wrapped=False) }}
   {% elif len(op.request_bodies) > 1 %}
     switch (request.body.index()) {
     {%- for num, body in enumerate(op.request_bodies) -%}
       case {{ num }}: {
-        {% if body.content_type != 'multipart/form-data' %}
-            http_request.headers(USERVER_NAMESPACE::clients::http::Headers{ {USERVER_NAMESPACE::http::headers::kContentType, "{{ body.content_type }}"} });
-        {% endif %}
-
         {% set body_obj = "std::get<" + str(num) + ">(request.body)" %}
-        {% if body.content_type == 'application/json' %}
-            {{ application_json.serialize(body_obj, "http_request") }}
-        {% elif body.content_type == 'multipart/form-data' %}
-            {{ application_multipartformdata.serialize(body, body_obj, "http_request") }}
-        {% elif body.content_type == 'application/x-www-form-urlencoded' %}
-            {{ application_xwwwformurlencoded.serialize(body, body_obj, "http_request") }}
-        {% else %}
-            {{ application_octetstream.serialize(body_obj, "http_request") }}
-        {% endif %}
-
+        {{ serialize_request_single_body(body, body_obj, "http_request", wrapped=True) }}
         break;
       }
     {% endfor %}

chaotic-openapi/chaotic_openapi/back/cpp/common/translator.py

@@ -389,6 +389,7 @@ def _validate_primitive_object(self, schema: cpp_types.CppType) -> None:
         assert schema.json_schema
         source_location = schema.json_schema.source_location()
 
+        schema = common_types.resolve_ref(schema)
         if not isinstance(schema, cpp_types.CppStruct):
             raise chaotic_error.BaseError(
                 full_filepath=source_location.filepath,
@@ -397,7 +398,7 @@ def _validate_primitive_object(self, schema: cpp_types.CppType) -> None:
                 msg='"application/x-www-form-urlencoded" body allows only "type: object"',
             )
         for field in schema.fields.values():
-            if not isinstance(field.schema, cpp_types.CppPrimitiveType):
+            if not isinstance(common_types.resolve_ref(field.schema), cpp_types.CppPrimitiveType):
                 raise chaotic_error.BaseError(
                     full_filepath=source_location.filepath,
                     infile_path=source_location.location,

chaotic-openapi/chaotic_openapi/back/cpp/common/types.py

@@ -8,6 +8,13 @@
 from chaotic_openapi.back.cpp.client import middleware
 
 
+def resolve_ref(schema: cpp_types.CppType) -> cpp_types.CppType:
+    """Follow the `$ref` chain down to the referenced type."""
+    while isinstance(schema, cpp_types.CppRef):
+        schema = schema.orig_cpp_type
+    return schema
+
+
 @dataclasses.dataclass
 class Security:
     auth_type: str
@@ -134,6 +141,13 @@ def cpp_type(self) -> str:
         assert self.schema is not None
         return self.schema.cpp_user_name()
 
+    def fields(self) -> dict[str, cpp_types.CppStructField]:
+        """Fields of a form body, with `$ref` resolved."""
+        assert self.schema is not None
+        schema = resolve_ref(self.schema)
+        assert isinstance(schema, cpp_types.CppStruct), schema
+        return schema.fields
+
 
 @dataclasses.dataclass
 class Response:

chaotic-openapi/chaotic_openapi/back/cpp/handler/templates/requests.cpp.jinja

@@ -24,7 +24,7 @@ namespace {{ spec.cpp_namespace }}::{{ op.cpp_namespace() }} {
 {% endmacro %}
 
 {% macro _parse_urlencoded(body, prefix) %}
-    {% for field_name, field in body.schema.fields.items() %}
+    {% for field_name, field in body.fields().items() %}
         {% if field.required %}
             if (!http_request.HasArg("{{ field_name }}")) {
                 throw {{ userver }}::server::handlers::ClientError(
@@ -49,7 +49,7 @@ namespace {{ spec.cpp_namespace }}::{{ op.cpp_namespace() }} {
 {% endmacro %}
 
 {% macro _parse_multipart(body, prefix) %}
-    {% for field_name, field in body.schema.fields.items() %}
+    {% for field_name, field in body.fields().items() %}
         {% if field.required %}
             if (!http_request.HasFormDataArg("{{ field_name }}")) {
                 throw {{ userver }}::server::handlers::ClientError(

chaotic-openapi/chaotic_openapi/front/parser.py

@@ -182,15 +182,20 @@ def _convert_swagger_request_body(
                     msg='"consumes" must be either "multipart/form-data" or "application/x-www-form-urlencoded" for "type: file"',
                 )
 
-        schema = self._parse_schema(
-            request_body.model_dump(
-                by_alias=True,
-                exclude={'name', 'in_', 'description', 'required', 'allowEmptyValue', 'collectionFormat'},
-                exclude_unset=True,
-            ),
-            infile_path,
-            allow_file=True,
+        field_schema = request_body.model_dump(
+            by_alias=True,
+            exclude={'name', 'in_', 'description', 'required', 'allowEmptyValue', 'collectionFormat'},
+            exclude_unset=True,
         )
+        object_schema: dict[str, Any] = {
+            'type': 'object',
+            'properties': {request_body.name: field_schema},
+            'additionalProperties': False,
+        }
+        if request_body.required:
+            object_schema['required'] = [request_body.name]
+
+        schema = self._parse_schema(object_schema, infile_path, allow_file=True)
         return [
             model.RequestBody(
                 content_type=mime,

chaotic-openapi/golden_tests/output/client/src/clients/test/requests.cpp

@@ -27,7 +27,9 @@ base_url + "/testme"
 openapi::WriteParameter<openapi::TrivialParameter<openapi::In::kQuery, knumber, std::string, std::string>>(request.number, sink);
 openapi::WriteParameter<openapi::ArrayParameter<openapi::In::kQuery, karray, ',', std::string, std::string>>(request.array, sink);
 
-http_request.data(ToString(USERVER_NAMESPACE::formats::json::ValueBuilder(request.body).ExtractValue()));
+sink.SetHeader(USERVER_NAMESPACE::http::headers::kContentType, "application/json");
+
+  http_request.data(ToString(USERVER_NAMESPACE::formats::json::ValueBuilder(request.body).ExtractValue()));
 
 sink.Flush();
 

chaotic-openapi/integration_tests/clients/multiple-content-types/openapi.yaml

@@ -10,54 +10,125 @@ paths:
                 content:
                     application/json:
                         schema:
-                            type: object
-                            properties:
-                                foo:
-                                    type: string
-                            additionalProperties: false
+                            $ref: '#/components/schemas/single-json'
                     multipart/form-data:
                         schema:
-                            type: object
-                            required:
-                              - filename
-                            properties:
-                                filename:
-                                    type: string
-                                content:
-                                    type: string
-                            additionalProperties: false
+                            $ref: '#/components/schemas/single-form-data'
                     application/x-www-form-urlencoded:
                         schema:
-                            type: object
-                            required:
-                              - name
-                              - age
-                            properties:
-                                name:
-                                    type: string
-                                password:
-                                    type: string
-                                age:
-                                    type: integer
-                                salary:
-                                    type: number
-                                is_smoking:
-                                    type: boolean
-                            additionalProperties: false
+                            $ref: '#/components/schemas/single-form-urlen'
                     application/octet-stream:
                         schema:
-                            type: string
+                            $ref: '#/components/schemas/single-octet'
             responses:
                 '200':
                     description: OK
                     content:
                         application/json:
                             schema:
-                                type: object
-                                properties:
-                                    bar:
-                                        type: string
-                                additionalProperties: false
+                                $ref: '#/components/schemas/common-response'
                         application/octet-stream:
                             schema:
                                 type: string
+    /test-single-json:
+        post:
+            requestBody:
+                content:
+                    application/json:
+                        schema:
+                            $ref: '#/components/schemas/single-json'
+            responses:
+                '200':
+                    description: OK
+                    content:
+                        application/json:
+                            schema:
+                                $ref: '#/components/schemas/common-response'
+
+    /test-single-form-data:
+        post:
+            requestBody:
+                content:
+                    multipart/form-data:
+                        schema:
+                            $ref: '#/components/schemas/single-form-data'
+            responses:
+                '200':
+                    description: OK
+                    content:
+                        application/json:
+                            schema:
+                                $ref: '#/components/schemas/common-response'
+
+    /test-single-form-urlen:
+        post:
+            requestBody:
+                content:
+                    application/x-www-form-urlencoded:
+                        schema:
+                            $ref: '#/components/schemas/single-form-urlen'
+            responses:
+                '200':
+                    description: OK
+                    content:
+                        application/json:
+                            schema:
+                                $ref: '#/components/schemas/common-response'
+
+    /test-single-octet:
+        post:
+            requestBody:
+                content:
+                    application/octet-stream:
+                        schema:
+                            $ref: '#/components/schemas/single-octet'
+            responses:
+                '200':
+                    description: OK
+                    content:
+                        application/octet-stream:
+                            schema:
+                                type: string                                
+components:
+    schemas:
+        single-json:
+            type: object
+            properties:
+                foo:
+                    type: string
+            additionalProperties: false
+        single-form-data:
+            type: object
+            required:
+                - filename
+            properties:
+                filename:
+                    type: string
+                content:
+                    type: string
+            additionalProperties: false
+        single-form-urlen:
+            type: object
+            required:
+                - name
+                - age
+            properties:
+                name:
+                    type: string
+                password:
+                    type: string
+                age:
+                    type: integer
+                salary:
+                    type: number
+                is_smoking:
+                    type: boolean
+            additionalProperties: false
+        single-octet:
+            type: string
+        common-response:
+            type: object
+            properties:
+                bar:
+                    type: string
+            additionalProperties: false

chaotic-openapi/integration_tests/clients/swagger-form-data/swagger.yaml

@@ -0,0 +1,22 @@
+swagger: '2.0'
+description: |
+    Swagger "in: formData" request body.
+
+    Such a parameter describes a single form field, not the whole body, so it is
+    wrapped into a one-property object schema (see
+    Parser._convert_swagger_request_body). Only one "in: formData" parameter per
+    operation is supported for now, the rest are silently dropped by the parser.
+
+paths:
+    /form-urlencoded:
+        post:
+            consumes:
+              - application/x-www-form-urlencoded
+            parameters:
+              - in: formData
+                name: name
+                required: true
+                type: string
+            responses:
+                '200':
+                    description: OK