Proxy errors and extensions in ProxySchema

ariadne_graphql_proxy/proxy_root_value.py

@@ -0,0 +1,30 @@
+from typing import List, Optional, Tuple
+
+from ariadne.types import BaseProxyRootValue, GraphQLResult
+
+
+class ProxyRootValue(BaseProxyRootValue):
+    __slots__ = ("root_value", "errors", "extensions")
+
+    def __init__(
+        self,
+        root_value: Optional[dict] = None,
+        errors: Optional[List[dict]] = None,
+        extensions: Optional[dict] = None,
+    ):
+        super().__init__(root_value)
+        self.errors = errors
+        self.extensions = extensions
+
+    def update_result(self, result: Tuple[bool, dict]) -> Tuple[bool, dict]:
+        success, data = super().update_result(result)
+
+        if self.errors:
+            data.setdefault("errors", [])
+            data["errors"] += self.errors
+
+        if self.extensions:
+            data.setdefault("extensions", {})
+            data["extensions"].update(self.extensions)
+
+        return success, data

ariadne_graphql_proxy/proxy_schema.py

@@ -1,9 +1,9 @@
 from asyncio import gather
 from functools import reduce
 from inspect import isawaitable
-from typing import Any, Callable, Dict, List, Optional, Set, Union
+from typing import Any, Callable, Dict, List, Optional, Set, Type, Union
 
-from ariadne.types import RootValue
+from ariadne.types import BaseProxyRootValue, RootValue
 from graphql import (
     DocumentNode,
     GraphQLInterfaceType,
@@ -17,6 +17,7 @@
 
 from .copy import copy_schema
 from .merge import merge_schemas
+from .proxy_root_value import ProxyRootValue
 from .query_filter import QueryFilter
 from .remote_schema import get_remote_schema
 from .standard_types import STANDARD_TYPES, add_missing_scalar_types
@@ -30,15 +31,24 @@
 
 
 class ProxySchema:
-    def __init__(self, root_value: Optional[RootValue] = None):
+    def __init__(
+        self,
+        root_value: Optional[RootValue] = None,
+        proxy_root_value: Type[ProxyRootValue] = ProxyRootValue,
+    ):
         self.schemas: List[GraphQLSchema] = []
         self.urls: List[Optional[str]] = []
         self.headers: List[Optional[ProxyHeaders]] = []
+        self.proxy_errors: List[bool] = []
+        self.proxy_extensions: List[bool] = []
+        self.labels: List[str] = []
         self.fields_map: Dict[str, Dict[str, Set[int]]] = {}
         self.fields_types: Dict[str, Dict[str, str]] = {}
         self.unions: Dict[str, List[str]] = {}
         self.foreign_keys: Dict[str, Dict[str, List[str]]] = {}
 
+        self.proxy_root_value = proxy_root_value
+
         self.schema: Optional[GraphQLSchema] = None
         self.query_filter: Optional[QueryFilter] = None
         self.root_value: Optional[RootValue] = root_value
@@ -54,12 +64,17 @@ def add_remote_schema(
         exclude_directives: Optional[List[str]] = None,
         exclude_directives_args: Optional[Dict[str, List[str]]] = None,
         extra_fields: Optional[Dict[str, List[str]]] = None,
+        label: Optional[str] = None,
+        proxy_errors: bool = True,
+        proxy_extensions: bool = True,
     ) -> int:
         if callable(headers):
             remote_schema = get_remote_schema(url, headers(None))
         else:
             remote_schema = get_remote_schema(url, headers)
 
+        schema_id = len(self.schemas)
+
         return self.add_schema(
             remote_schema,
             url,
@@ -70,6 +85,9 @@ def add_remote_schema(
             exclude_directives=exclude_directives,
             exclude_directives_args=exclude_directives_args,
             extra_fields=extra_fields,
+            label=label or f"remote_{schema_id}",
+            proxy_errors=proxy_errors,
+            proxy_extensions=proxy_extensions,
         )
 
     def add_schema(
@@ -84,6 +102,9 @@ def add_schema(
         exclude_directives: Optional[List[str]] = None,
         exclude_directives_args: Optional[Dict[str, List[str]]] = None,
         extra_fields: Optional[Dict[str, List[str]]] = None,
+        label: Optional[str] = None,
+        proxy_errors: bool = True,
+        proxy_extensions: bool = True,
     ) -> int:
         if (
             exclude_types
@@ -103,11 +124,15 @@ def add_schema(
 
         schema.type_map = add_missing_scalar_types(schema.type_map)
 
+        schema_id = len(self.schemas)
+
         self.schemas.append(schema)
         self.urls.append(url)
         self.headers.append(headers)
+        self.labels.append(label or f"schema_{schema_id}")
+        self.proxy_errors.append(proxy_errors)
+        self.proxy_extensions.append(proxy_extensions)
 
-        schema_id = len(self.schemas) - 1
         for type_name, type_def in schema.type_map.items():
             if type_name in STANDARD_TYPES:
                 continue
@@ -241,9 +266,13 @@ async def root_resolver(
         if not queries:
             return root_value
 
+        root_errors: List[dict] = []
+        root_extensions: dict = {}
+
         subqueries_data = await gather(
             *[
                 self.fetch_data(
+                    schema_id,
                     context_value,
                     self.urls[schema_id],
                     self.headers[schema_id],
@@ -266,13 +295,31 @@ async def root_resolver(
             ]
         )
 
-        for subquery_data in subqueries_data:
-            if subquery_data:
-                root_value.update(subquery_data)
+        for schema_id, subquery_data in subqueries_data:
+            label = self.labels[schema_id]
+            if isinstance(subquery_data.get("data"), dict):
+                root_value.update(subquery_data["data"])
+            if (
+                isinstance(subquery_data.get("errors"), list)
+                and self.proxy_errors[schema_id]
+            ):
+                root_errors += self.clean_errors(label, subquery_data["errors"])
+            if (
+                isinstance(subquery_data.get("extensions"), dict)
+                and self.proxy_extensions[schema_id]
+            ):
+                root_extensions[label] = subquery_data["extensions"]
+
+        if root_errors or root_extensions:
+            return self.proxy_root_value(
+                root_value,
+                root_errors or None,
+                root_extensions or None,
+            )
 
         return root_value or None
 
-    async def fetch_data(self, context, url, headers, json):
+    async def fetch_data(self, schema_id, context, url, headers, json):
         async with AsyncClient() as client:
             if callable(headers):
                 headers = headers(context)
@@ -284,4 +331,12 @@ async def fetch_data(self, context, url, headers, json):
             )
 
             query_data = r.json()
-            return query_data.get("data")
+            return (schema_id, query_data)
+
+    def clean_errors(self, label: str, errors: List[dict]) -> List[dict]:
+        clean_errors: List[dict] = []
+        for error in errors:
+            if isinstance(error, dict) and isinstance(error.get("path"), list):
+                error["path"].insert(0, label)
+                clean_errors.append(error)
+        return clean_errors

pyproject.toml

@@ -19,7 +19,11 @@ classifiers = [
   "Topic :: Software Development :: Libraries :: Python Modules",
 ]
 version = "0.2.0"
-dependencies = ["graphql-core>=3.2.0,<3.3", "httpx", "ariadne"]
+dependencies = [
+  "graphql-core>=3.2.0,<3.3",
+  "httpx",
+  "ariadne>=0.23",
+]
 
 [project.optional-dependencies]
 test = [