Align API error envelopes

backend/app/main.py

@@ -11,13 +11,17 @@ from app.core.errors import AppError
 from app.core.logging import configure_logging
 
 
-def _to_error_payload(code: str, message: str, details: dict | list | None = None) -> dict:
+def _to_error_payload(
+    code: str,
+    message: str,
+    details: dict | list | None = None,
+    request_id: str | None = None,
+) -> dict:
     return {
-        "error": {
-            "code": code,
-            "message": message,
-            "details": details or {},
-        },
+        "error": code,
+        "message": message,
+        "details": details or {},
+        "request_id": request_id,
     }
 
 
@@ -58,28 +62,56 @@ def create_app() -> FastAPI:
     async def app_error(request: Request, exc: AppError):  # noqa: ARG001
         return JSONResponse(
             status_code=exc.status_code,
-            content=_to_error_payload(exc.code, exc.message, exc.details),
+            content=_to_error_payload(
+                exc.code,
+                exc.message,
+                exc.details,
+                request_id=request.headers.get("x-request-id"),
+            ),
         )
 
     @app.exception_handler(HTTPException)
     async def http_error(request: Request, exc: HTTPException):  # noqa: ARG001
+        code = "HTTP_ERROR"
+        message = str(exc.detail)
+        details = {}
+        if isinstance(exc.detail, dict):
+            code = str(exc.detail.get("error") or exc.detail.get("code") or code)
+            message = str(exc.detail.get("message") or message)
+            raw_details = exc.detail.get("details")
+            details = raw_details if isinstance(raw_details, (dict, list)) else {}
         return JSONResponse(
             status_code=exc.status_code,
-            content=_to_error_payload("HTTP_ERROR", str(exc.detail), {}),
+            content=_to_error_payload(
+                code,
+                message,
+                details,
+                request_id=request.headers.get("x-request-id"),
+            ),
         )
 
     @app.exception_handler(RequestValidationError)
     async def validation_error(request: Request, exc: RequestValidationError):  # noqa: ARG001
         return JSONResponse(
             status_code=422,
-            content=_to_error_payload("VALIDATION_ERROR", "Validation failed", exc.errors()),
+            content=_to_error_payload(
+                "VALIDATION_ERROR",
+                "Validation failed",
+                exc.errors(),
+                request_id=request.headers.get("x-request-id"),
+            ),
         )
 
     @app.exception_handler(Exception)
     async def unexpected_error(request: Request, exc: Exception):  # noqa: ARG001
         return JSONResponse(
             status_code=500,
-            content=_to_error_payload("INTERNAL_ERROR", "Unexpected server error", {"type": exc.__class__.__name__}),
+            content=_to_error_payload(
+                "INTERNAL_ERROR",
+                "Unexpected server error",
+                {"type": exc.__class__.__name__},
+                request_id=request.headers.get("x-request-id"),
+            ),
         )
 
     return app