Add option to filter errors from being reported

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - Allow an optional function to resolve the `rootValue`, passing the `DocumentNode` AST to determine the value. [PR #1555](https://github.com/apollographql/apollo-server/pull/1555)
 - Follow-up on the work in [PR #1516](https://github.com/apollographql/apollo-server/pull/1516) to also fix missing insertion cursor/caret when a custom GraphQL configuration is specified which doesn't specify its own `cursorShape` property. [PR #1607](https://github.com/apollographql/apollo-server/pull/1607)
+- Add option to filter errors from being reported [#1639](https://github.com/apollographql/apollo-server/pull/1639)
 
 ### v2.1.0
 

docs/source/api/apollo-server.md

@@ -362,6 +362,9 @@ addMockFunctionsToSchema({
    'sendReport()' on other signals if you'd like. Note that 'sendReport()'
    does not run synchronously so it cannot work usefully in an 'exit' handler.
 
-*  `maskErrorDetails`: boolean
+* `filterErrors`: (err: Error) => Error | null
 
-   Set to true to remove error details from the traces sent to Apollo's servers. Defaults to false.
+   By default, all errors get reported to Engine servers. You can specify a
+   a filter function to exclude specific errors from being reported by
+   returning null, or you can mask certain details of the error and return the
+   error to be reported.

packages/apollo-engine-reporting/src/agent.ts

@@ -1,6 +1,6 @@
 import os from 'os';
 import { gzip } from 'zlib';
-import { DocumentNode } from 'graphql';
+import { DocumentNode, GraphQLError } from 'graphql';
 import {
   FullTracesReport,
   ReportHeader,
@@ -86,8 +86,12 @@ export interface EngineReportingOptions {
   handleSignals?: boolean;
   // Sends the trace report immediately. This options is useful for stateless environments
   sendReportsImmediately?: boolean;
-  // To remove the error message from traces, set this to true. Defaults to false
-  maskErrorDetails?: boolean;
+  // By default, all errors get reported to Engine servers. You can specify a
+  // a filter function to exclude specific errors from being reported by
+  // returning null, or you can mask certain details of the error and return the
+  // error to be reported.
+  // If set to 'true' instead of a function, it will mask the error details.
+  filterErrors?: ((err: GraphQLError) => GraphQLError | null) | boolean;
 
   /**
    * (Experimental) Creates the client information for operation traces.

packages/apollo-engine-reporting/src/extension.ts

@@ -49,8 +49,18 @@ export class EngineReportingExtension<TContext = any>
     options: EngineReportingOptions,
     addTrace: (signature: string, operationName: string, trace: Trace) => void,
   ) {
+    const filterErrors = (() => {
+      if (options.filterErrors === true) {
+        return (error: GraphQLError) => new GraphQLError('masked', error.nodes);
+      } else if (options.filterErrors) {
+        return options.filterErrors;
+      } else {
+        return (error: GraphQLError) => error;
+      }
+    })();
+
     this.options = {
-      maskErrorDetails: false,
+      filterErrors,
       ...options,
     };
     this.addTrace = addTrace;
@@ -261,18 +271,21 @@ export class EngineReportingExtension<TContext = any>
           }
         }
 
-        // Always send the trace errors, so that the UI acknowledges that there is an error.
-        const errorInfo = this.options.maskErrorDetails
-          ? { message: '<masked>' }
-          : {
-              message: error.message,
-              location: (error.locations || []).map(
-                ({ line, column }) => new Trace.Location({ line, column }),
-              ),
-              json: JSON.stringify(error),
-            };
+        const filteredError = this.options.filterErrors
+          ? this.options.filterErrors(error)
+          : error;
 
-        node!.error!.push(new Trace.Error(errorInfo));
+        if (filteredError) {
+          const errorInfo = {
+            message: filteredError.message,
+            location: (filteredError.locations || []).map(
+              ({ line, column }) => new Trace.Location({ line, column }),
+            ),
+            json: JSON.stringify(filteredError),
+          };
+
+          node!.error!.push(new Trace.Error(errorInfo));
+        }
       });
     }
   }