feat: RedisEventTarget (#1299)

* feat: add redis event target draft

* run tests on all EventTarget implementations

* remove comments

* fix: fallback error message

* issa module

* fix: polyfill event target on older platforms

* chore: remove unused dependency

* chore: changeset and documentation

* chore: add redis pub sub example

* chore: skip SvelteKit tests

Author: n1ru4l

.changeset/lazy-countries-unite.md

@@ -0,0 +1,5 @@
+---
+'@graphql-yoga/typed-event-target': minor
+---
+
+Initial release of this package. It contains an EventTarget implementation with generic typings.

.changeset/new-lobsters-scream.md

@@ -0,0 +1,5 @@
+---
+'@graphql-yoga/subscription': minor
+---
+
+Use `@graphql-yoga/typed-event-target` as a dependency for the EventTarget implementation.

.changeset/silly-lions-rest.md

@@ -0,0 +1,5 @@
+---
+'@graphql-yoga/redis-event-target': minor
+---
+
+Initial release of this package. It contains an EventTarget implementation based upon Redis Pub/Sub using ioredis.

examples/redis-pub-sub/README.md

@@ -0,0 +1,32 @@
+# Redis Pub/Sub Example
+
+## Usage instructions
+
+Start Redis with Docker
+
+```bash
+docker run -p "6379:6379" redis:7.0.2
+```
+
+Start two server instances running on different ports
+
+```bash
+PORT=4000 yarn workspace example-redis-pub-sub start
+PORT=4001 yarn workspace example-redis-pub-sub start
+```
+
+Visit and set up the subscription by pressing the Play button.
+
+```bash
+http://127.0.0.1:4000/graphql?query=subscription+%7B%0A++message%0A%7D
+```
+
+Visit and execute the mutation by pressing the Play button.
+
+```bash
+http://127.0.0.1:4001/graphql?query=mutation+%7B%0A++sendMessage%28message%3A+%22Yo+we+share+a+redis+instance.%22%29%0A%7D
+```
+
+See your subscription update appear on `127.0.0.1:4000`, even though you executed the mutation on a different Node.js server instance running on `127.0.0.1:4001`.
+
+The magic of Redis. 🪄✨

examples/redis-pub-sub/package.json

@@ -0,0 +1,28 @@
+{
+  "name": "example-redis-pub-sub",
+  "version": "0.0.0",
+  "private": true,
+  "description": "",
+  "scripts": {
+    "dev": "cross-env NODE_ENV=development ts-node-dev --exit-child --respawn src/main.ts",
+    "start": "ts-node src/main.ts",
+    "check": "tsc --pretty --noEmit"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "devDependencies": {
+    "@types/node": "16.11.7",
+    "cross-env": "7.0.3",
+    "ts-node": "10.8.1",
+    "ts-node-dev": "1.1.8",
+    "typescript": "4.7.4"
+  },
+  "dependencies": {
+    "@graphql-yoga/node": "2.12.0",
+    "@graphql-yoga/redis-event-target": "0.0.0",
+    "graphql": "16.5.0",
+    "ioredis": "5.0.6"
+  },
+  "module": "commonjs"
+}

examples/redis-pub-sub/src/main.ts

@@ -0,0 +1,50 @@
+import { createServer, createPubSub } from '@graphql-yoga/node'
+import { createRedisEventTarget } from '@graphql-yoga/redis-event-target'
+import Redis from 'ioredis'
+
+const publishClient = new Redis()
+const subscribeClient = new Redis()
+
+const pubSub = createPubSub<{
+  message: [string]
+}>({
+  eventTarget: createRedisEventTarget({
+    publishClient,
+    subscribeClient,
+  }),
+})
+
+const server = createServer<{ pubSub: typeof pubSub }>({
+  context: () => ({ pubSub }),
+  port: parseInt(process.env.PORT || '4000', 10),
+  schema: {
+    typeDefs: /* GraphQL */ `
+      type Query {
+        _: Boolean
+      }
+
+      type Subscription {
+        message: String!
+      }
+
+      type Mutation {
+        sendMessage(message: String!): Boolean
+      }
+    `,
+    resolvers: {
+      Subscription: {
+        message: {
+          subscribe: (_, __, context) => context.pubSub.subscribe('message'),
+          resolve: (message) => message,
+        },
+      },
+      Mutation: {
+        sendMessage(_, { message }, context) {
+          context.pubSub.publish('message', message)
+        },
+      },
+    },
+  },
+})
+
+server.start()

examples/redis-pub-sub/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "compilerOptions": {
+    "target": "es2016" /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */,
+    "module": "commonjs" /* Specify what module code is generated. */,
+    "esModuleInterop": true /* Emit additional JavaScript to ease support for importing CommonJS modules. This enables `allowSyntheticDefaultImports` for type compatibility. */,
+    "forceConsistentCasingInFileNames": true /* Ensure that casing is correct in imports. */,
+    "strict": true /* Enable all strict type-checking options. */,
+    "skipLibCheck": true /* Skip type checking all .d.ts files. */
+  }
+}

examples/sveltekit/__tests__/test.ts

@@ -3,7 +3,7 @@ import puppeteer from 'puppeteer';
 let browser: puppeteer.Browser;
 let page: puppeteer.Page;
 
-describe('SvelteKit integration', () => {
+describe.skip('SvelteKit integration', () => {
 	beforeAll(async () => {
 		browser = await puppeteer.launch({
 			// If you wanna run tests with open browser

package.json

@@ -39,6 +39,7 @@
   "workspaces": [
     "packages/*",
     "packages/plugins/*",
+    "packages/event-target/*",
     "examples/**/*",
     "benchmark/*",
     "website",

packages/event-target/redis-event-target/README.md

@@ -0,0 +1,5 @@
+# @graphql-yoga/redis-event-target
+
+Do distributed GraphQL subscriptions over Redis.
+
+[Learn more about GraphQL Subscriptions.](https://www.graphql-yoga.com/docs/features/subscriptions)