feat(router): Response Reformatting Errors

.changesets/feat_tylerb_add_result_coercion_errors.md

@@ -0,0 +1,8 @@
+### Response reformatting and result coercion errors ([PR #8441](https://github.com/apollographql/router/pull/8441))
+
+All subgraph responses are checked and corrected to ensure alignment with the
+schema and query. When a misaligned value is returned, it is nullified. Now,
+when the feature is enabled, an errors for this nullification are included in
+the errors array in the response.
+
+By [@TylerBloom](https://github.com/TylerBloom) in https://github.com/apollographql/router/pull/8441

apollo-router/src/configuration/mod.rs

@@ -732,6 +732,14 @@ pub(crate) struct Supergraph {
     /// but request handling will stop immediately when the client connection is closed.
     pub(crate) early_cancel: bool,
 
+    /// Enable errors generated during response reformatting and result coercion to be returned in
+    /// responses.
+    /// Default: false
+    /// All subgraph responses are checked and corrected to ensure alignment with the schema and
+    /// query. When enabled, misaligned values will generate errors which are included in errors
+    /// array in the response.
+    pub(crate) enable_result_coercion_errors: bool,
+
     /// Log a message if the client closes the connection before the response is sent.
     /// Default: false.
     pub(crate) experimental_log_on_broken_pipe: bool,
@@ -758,6 +766,7 @@ impl Supergraph {
         generate_query_fragments: Option<bool>,
         early_cancel: Option<bool>,
         experimental_log_on_broken_pipe: Option<bool>,
+        insert_result_coercion_errors: Option<bool>,
     ) -> Self {
         Self {
             listen: listen.unwrap_or_else(default_graphql_listen),
@@ -771,6 +780,7 @@ impl Supergraph {
                 .unwrap_or_else(default_generate_query_fragments),
             early_cancel: early_cancel.unwrap_or_default(),
             experimental_log_on_broken_pipe: experimental_log_on_broken_pipe.unwrap_or_default(),
+            enable_result_coercion_errors: insert_result_coercion_errors.unwrap_or_default(),
         }
     }
 }
@@ -789,6 +799,7 @@ impl Supergraph {
         generate_query_fragments: Option<bool>,
         early_cancel: Option<bool>,
         experimental_log_on_broken_pipe: Option<bool>,
+        insert_result_coercion_errors: Option<bool>,
     ) -> Self {
         Self {
             listen: listen.unwrap_or_else(test_listen),
@@ -802,6 +813,7 @@ impl Supergraph {
                 .unwrap_or_else(default_generate_query_fragments),
             early_cancel: early_cancel.unwrap_or_default(),
             experimental_log_on_broken_pipe: experimental_log_on_broken_pipe.unwrap_or_default(),
+            enable_result_coercion_errors: insert_result_coercion_errors.unwrap_or_default(),
         }
     }
 }

apollo-router/src/configuration/snapshots/apollo_router__configuration__tests__schema_generation.snap

@@ -10496,6 +10496,11 @@ expression: "&schema"
           "description": "abort request handling when the client drops the connection.\nDefault: false.\nWhen set to true, some parts of the request pipeline like telemetry will not work properly,\nbut request handling will stop immediately when the client connection is closed.",
           "type": "boolean"
         },
+        "enable_result_coercion_errors": {
+          "default": false,
+          "description": "Enable errors generated during response reformatting and result coercion to be returned in\nresponses.\nDefault: false\nAll subgraph responses are checked and corrected to ensure alignment with the schema and\nquery. When enabled, misaligned values will generate errors which are included in errors\narray in the response.",
+          "type": "boolean"
+        },
         "experimental_log_on_broken_pipe": {
           "default": false,
           "description": "Log a message if the client closes the connection before the response is sent.\nDefault: false.",
@@ -12076,6 +12081,7 @@ expression: "&schema"
         },
         "defer_support": true,
         "early_cancel": false,
+        "enable_result_coercion_errors": false,
         "experimental_log_on_broken_pipe": false,
         "generate_query_fragments": true,
         "introspection": false,

apollo-router/src/services/execution/service.rs

@@ -29,6 +29,7 @@ use tracing::Span;
 use tracing::event;
 use tracing_core::Level;
 
+use crate::Configuration;
 use crate::apollo_studio_interop::ReferencedEnums;
 use crate::apollo_studio_interop::extract_enums_from_response;
 use crate::graphql::Error;
@@ -64,6 +65,7 @@ pub(crate) struct ExecutionService {
     pub(crate) schema: Arc<Schema>,
     pub(crate) subgraph_schemas: Arc<SubgraphSchemas>,
     pub(crate) fetch_service_factory: Arc<FetchServiceFactory>,
+    pub(crate) configuration: Arc<Configuration>,
     /// Subscription config if enabled
     subscription_config: Option<SubscriptionConfig>,
     apollo_telemetry_config: Option<ApolloTelemetryConfig>,
@@ -192,6 +194,8 @@ impl ExecutionService {
         };
 
         let execution_span = Span::current();
+        let insert_result_coercion_errors =
+            self.configuration.supergraph.enable_result_coercion_errors;
 
         let stream = stream
             .map(move |mut response: Response| {
@@ -243,6 +247,7 @@ impl ExecutionService {
                         &mut nullified_paths,
                         metrics_ref_mode,
                         &context,
+                        insert_result_coercion_errors,
                         response,
                     )
                 }))
@@ -261,6 +266,7 @@ impl ExecutionService {
         nullified_paths: &mut Vec<Path>,
         metrics_ref_mode: ApolloMetricsReferenceMode,
         context: &crate::Context,
+        insert_result_coercion_errors: bool,
         mut response: Response,
     ) -> Option<Response> {
         // responses that would fall under a path that was previously nullified are not sent
@@ -330,6 +336,7 @@ impl ExecutionService {
                     variables.clone(),
                     schema.api_schema(),
                     variables_set,
+                    insert_result_coercion_errors
                 );
             }
 
@@ -340,6 +347,7 @@ impl ExecutionService {
                         variables.clone(),
                         schema.api_schema(),
                         variables_set,
+                        insert_result_coercion_errors
                     )
                     ,
             );
@@ -635,6 +643,7 @@ pub(crate) struct ExecutionServiceFactory {
     pub(crate) subgraph_schemas: Arc<SubgraphSchemas>,
     pub(crate) plugins: Arc<Plugins>,
     pub(crate) fetch_service_factory: Arc<FetchServiceFactory>,
+    pub(crate) configuration: Arc<Configuration>,
 }
 
 impl ServiceFactory<ExecutionRequest> for ExecutionServiceFactory {
@@ -663,6 +672,7 @@ impl ServiceFactory<ExecutionRequest> for ExecutionServiceFactory {
                         subscription_config: subscription_plugin_conf,
                         subgraph_schemas: self.subgraph_schemas.clone(),
                         apollo_telemetry_config: apollo_telemetry_conf,
+                        configuration: Arc::clone(&self.configuration),
                     }
                     .boxed(),
                     |acc, (_, e)| e.execution_service(acc),

apollo-router/src/services/supergraph/service.rs

@@ -561,6 +561,7 @@ impl PluggableSupergraphServiceBuilder {
             subgraph_schemas: query_planner_service.subgraph_schemas(),
             plugins: self.plugins.clone(),
             fetch_service_factory,
+            configuration: Arc::clone(&configuration),
         };
 
         let execution_service: execution::BoxCloneService = ServiceBuilder::new()

apollo-router/src/services/supergraph/snapshots/apollo_router__services__supergraph__tests__deferred_fragment_bounds_nullability-2.snap

@@ -1,5 +1,6 @@
 ---
 source: apollo-router/src/services/supergraph/tests.rs
+assertion_line: 800
 expression: stream.next_response().await.unwrap()
 ---
 {
@@ -31,7 +32,7 @@ expression: stream.next_response().await.unwrap()
       "extensions": {
         "valueCompletion": [
           {
-            "message": "Cannot return null for non-nullable field Organization.nonNullId",
+            "message": "Null value found for non-nullable type ID",
             "path": [
               "currentUser",
               "activeOrganization",
@@ -68,7 +69,7 @@ expression: stream.next_response().await.unwrap()
       "extensions": {
         "valueCompletion": [
           {
-            "message": "Cannot return null for non-nullable field Organization.nonNullId",
+            "message": "Null value found for non-nullable type ID",
             "path": [
               "currentUser",
               "activeOrganization",
@@ -105,7 +106,7 @@ expression: stream.next_response().await.unwrap()
       "extensions": {
         "valueCompletion": [
           {
-            "message": "Cannot return null for non-nullable field Organization.nonNullId",
+            "message": "Null value found for non-nullable type ID",
             "path": [
               "currentUser",
               "activeOrganization",

apollo-router/src/services/supergraph/snapshots/apollo_router__services__supergraph__tests__filter_nullified_deferred_responses-2.snap

@@ -1,5 +1,6 @@
 ---
 source: apollo-router/src/services/supergraph/tests.rs
+assertion_line: 1679
 expression: deferred
 ---
 {
@@ -15,7 +16,7 @@ expression: deferred
       "extensions": {
         "valueCompletion": [
           {
-            "message": "Cannot return null for non-nullable field Organization.nonNullId",
+            "message": "Null value found for non-nullable type ID",
             "path": [
               "currentUser",
               "org",

apollo-router/src/services/supergraph/snapshots/apollo_router__services__supergraph__tests__nullability_bubbling.snap

@@ -1,5 +1,6 @@
 ---
 source: apollo-router/src/services/supergraph/tests.rs
+assertion_line: 435
 expression: response
 ---
 {
@@ -11,7 +12,7 @@ expression: response
   "extensions": {
     "valueCompletion": [
       {
-        "message": "Cannot return null for non-nullable field Organization.nonNullId",
+        "message": "Null value found for non-nullable type ID",
         "path": [
           "currentUser",
           "activeOrganization"