Request Batching in the gateway level (#5633)

ardatan · Jul 3, 2023 · d0d4917 · d0d4917
1 parent e5e2955
commit d0d4917
Show file tree

Hide file tree

Showing 8 changed files with 57 additions and 9 deletions.
diff --git a/.changeset/early-onions-destroy.md b/.changeset/early-onions-destroy.md
@@ -0,0 +1,7 @@
+---
+'@graphql-mesh/types': patch
+'@graphql-mesh/http': patch
+'@graphql-mesh/cli': patch
+---
+
+Request Batching on the gateway
diff --git a/packages/cli/src/commands/serve/yaml-config.graphql b/packages/cli/src/commands/serve/yaml-config.graphql
@@ -62,6 +62,10 @@ type ServeConfig @md {
   [Learn more](https://expressjs.com/en/guide/behind-proxies.html)
   """
   trustProxy: String
+  """
+  Enable and define a limit for [Request Batching](https://github.com/graphql/graphql-over-http/blob/main/rfcs/Batching.md)
+  """
+  batchingLimit: Int
 }
 
 union Port = Int | String

diff --git a/packages/http/src/graphqlHandler.ts b/packages/http/src/graphqlHandler.ts
@@ -1,13 +1,21 @@
 import { CORSOptions, createYoga, useLogger } from 'graphql-yoga';
 import { MeshInstance } from '@graphql-mesh/runtime';
 
-export const graphqlHandler = (
-  getBuiltMesh: () => Promise<MeshInstance>,
-  playgroundTitle: string,
-  playgroundEnabled: boolean,
-  graphqlEndpoint: string,
-  corsConfig: CORSOptions,
-) => {
+export const graphqlHandler = ({
+  getBuiltMesh,
+  playgroundTitle,
+  playgroundEnabled,
+  graphqlEndpoint,
+  corsConfig,
+  batchingLimit,
+}: {
+  getBuiltMesh: () => Promise<MeshInstance>;
+  playgroundTitle: string;
+  playgroundEnabled: boolean;
+  graphqlEndpoint: string;
+  corsConfig: CORSOptions;
+  batchingLimit?: number;
+}) => {
   let yoga$: Promise<ReturnType<typeof createYoga>>;
   return (request: Request, ctx: any) => {
     if (!yoga$) {
@@ -32,6 +40,7 @@ export const graphqlHandler = (
           cors: corsConfig,
           graphqlEndpoint,
           landingPage: false,
+          batching: batchingLimit ? { limit: batchingLimit } : false,
         }),
       );
     }

diff --git a/packages/http/src/index.ts b/packages/http/src/index.ts
@@ -28,12 +28,20 @@ export function createMeshHTTPHandler<TServerContext>({
     staticFiles,
     playground: playgroundEnabled,
     endpoint: graphqlPath = '/graphql',
+    batchingLimit,
     // TODO
     // trustProxy = 'loopback',
   } = rawServeConfig;
 
   return createServerAdapter<TServerContext>(
-    graphqlHandler(() => mesh$, playgroundTitle, playgroundEnabled, graphqlPath, corsConfig),
+    graphqlHandler({
+      getBuiltMesh: () => mesh$,
+      playgroundTitle,
+      playgroundEnabled,
+      graphqlEndpoint: graphqlPath,
+      corsConfig,
+      batchingLimit,
+    }),
     {
       plugins: [
         {

diff --git a/packages/types/src/config-schema.json b/packages/types/src/config-schema.json
@@ -161,6 +161,10 @@
         "trustProxy": {
           "type": "string",
           "description": "Configure Express Proxy Handling\n[Learn more](https://expressjs.com/en/guide/behind-proxies.html)"
+        },
+        "batchingLimit": {
+          "type": "integer",
+          "description": "Enable and define a limit for [Request Batching](https://github.com/graphql/graphql-over-http/blob/main/rfcs/Batching.md)"
         }
       }
     },

diff --git a/packages/types/src/config.ts b/packages/types/src/config.ts
@@ -112,6 +112,10 @@ export interface ServeConfig {
    * [Learn more](https://expressjs.com/en/guide/behind-proxies.html)
    */
   trustProxy?: string;
+  /**
+   * Enable and define a limit for [Request Batching](https://github.com/graphql/graphql-over-http/blob/main/rfcs/Batching.md)
+   */
+  batchingLimit?: number;
 }
 /**
  * Configuration for CORS

diff --git a/website/src/generated-markdown/ServeConfig.generated.md b/website/src/generated-markdown/ServeConfig.generated.md
@@ -27,4 +27,5 @@ This feature can be disabled by passing `false` One of:
   * `Boolean`
 * `playgroundTitle` (type: `String`) - Title of GraphiQL Playground
 * `trustProxy` (type: `String`) - Configure Express Proxy Handling
-[Learn more](https://expressjs.com/en/guide/behind-proxies.html)
+[Learn more](https://expressjs.com/en/guide/behind-proxies.html)
+* `batchingLimit` (type: `Int`) - Enable and define a limit for [Request Batching](https://github.com/graphql/graphql-over-http/blob/main/rfcs/Batching.md)
diff --git a/website/src/pages/docs/guides/batching.mdx b/website/src/pages/docs/guides/batching.mdx
@@ -150,3 +150,14 @@ Mesh Gateway->>Book.author resolver: Query.stores[0].bookSells[0].book[6].author
 Mesh Gateway->>Book.author resolver: Query.stores[0].bookSells[0].book[7].author
 Book.author resolver->>Authors API: GetAuthors(input: \{ ids: ["123", "754", "332"] \})
 ```
+
+# Request Batching on the gateway level
+
+Mesh also provides a way to batch requests on the gateway level. This is useful when you want to
+send multiple requests to the gateway in a single HTTP request. This follows
+[Batching RFC](https://github.com/graphql/graphql-over-http/blob/main/rfcs/Batching.md)
+
+```yaml
+serve:
+  batchingLimit: 10 # You have to define an explicit limit for batching
+```