Added an option to support additional extensions

(Originally #934, tweaked by @glasser.)

docs/source/setup.md

@@ -107,13 +107,16 @@ const GraphQLOptions = {
   validationRules?: Array<ValidationRule>,
 
   // a function applied to each graphQL execution result
-  formatResponse?: Function
+  formatResponse?: Function,
 
   // a custom default field resolver
-  fieldResolver?: Function
+  fieldResolver?: Function,
 
   // a boolean that will print additional debug logging if execution errors occur
-  debug?: boolean
+  debug?: boolean,
+
+  // (optional) extra GraphQL extensions from graphql-extensions
+  extensions?: Array<GraphQLExtension>
 }
 ```
 

packages/apollo-server-core/src/graphqlOptions.ts

@@ -19,6 +19,7 @@ import { GraphQLExtension } from 'graphql-extensions';
  * - (optional) formatResponse: a function applied to each graphQL execution result
  * - (optional) fieldResolver: a custom default field resolver
  * - (optional) debug: a boolean that will print additional debug logging if execution errors occur
+ * - (optional) extensions: an array of GraphQLExtension
  *
  */
 export interface GraphQLServerOptions<
@@ -39,6 +40,7 @@ export interface GraphQLServerOptions<
   tracing?: boolean;
   // cacheControl?: boolean | CacheControlExtensionOptions;
   cacheControl?: boolean | any;
+  extensions?: Array<typeof GraphQLExtension | GraphQLExtension>;
 }
 
 export default GraphQLServerOptions;

packages/apollo-server-core/src/runHttpQuery.ts

@@ -255,6 +255,7 @@ export async function runHttpQuery(
         tracing: optionsObject.tracing,
         cacheControl: optionsObject.cacheControl,
         request: request.request,
+        extensions: optionsObject.extensions,
       };
 
       if (optionsObject.formatParams) {

packages/apollo-server-core/src/runQuery.test.ts

@@ -20,6 +20,7 @@ import { LogAction, LogStep } from './logging';
 // environment.
 import { makeCompatible } from 'meteor-promise';
 import Fiber = require('fibers');
+import { GraphQLExtensionStack, GraphQLExtension } from 'graphql-extensions';
 makeCompatible(Promise, Fiber);
 
 const queryType = new GraphQLObjectType({
@@ -366,6 +367,53 @@ describe('runQuery', () => {
     });
   });
 
+  describe('graphql extensions', () => {
+    class CustomExtension implements GraphQLExtension<any> {
+      format(): [string, any] {
+        return ['customExtension', { foo: 'bar' }];
+      }
+    }
+
+    it('creates the extension stack', async () => {
+      const query = `{ testString }`;
+      const expected = { testString: 'it works' };
+      const extensions = [CustomExtension];
+      return runQuery({
+        schema: new GraphQLSchema({
+          query: new GraphQLObjectType({
+            name: 'QueryType',
+            fields: {
+              testString: {
+                type: GraphQLString,
+                resolve(root, args, context) {
+                  expect(context._extensionStack).to.be.instanceof(
+                    GraphQLExtensionStack,
+                  );
+                  expect(
+                    context._extensionStack.extensions[0],
+                  ).to.be.instanceof(CustomExtension);
+                },
+              },
+            },
+          }),
+        }),
+        query,
+        extensions,
+      });
+    });
+
+    it('runs format response from extensions', async () => {
+      const query = `{ testString }`;
+      const expected = { testString: 'it works' };
+      const extensions = [CustomExtension];
+      return runQuery({ schema, query: query, extensions }).then(res => {
+        return expect(res.extensions).to.deep.equal({
+          customExtension: { foo: 'bar' },
+        });
+      });
+    });
+  });
+
   describe('async_hooks', () => {
     let asyncHooks;
     let asyncHook;

packages/apollo-server-core/src/runQuery.ts

@@ -64,6 +64,7 @@ export interface QueryOptions {
   // cacheControl?: boolean | CacheControlExtensionOptions;
   cacheControl?: boolean | any;
   request: Request;
+  extensions?: Array<typeof GraphQLExtension | GraphQLExtension>;
 }
 
 function isQueryOperation(query: DocumentNode, operationName: string) {
@@ -98,7 +99,7 @@ function doRunQuery(options: QueryOptions): Promise<GraphQLResponse> {
   logFunction({ action: LogAction.request, step: LogStep.start });
 
   const context = options.context || {};
-  let extensions = [];
+  let extensions = options.extensions !== undefined ? options.extensions : [];
   if (options.tracing) {
     extensions.push(TracingExtension);
   }