Add support for graphql subscriptions & generate random msgs

aiswarm · Nov 18, 2023 · 254cad6 · 254cad6
1 parent 8054377
commit 254cad6
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Showing 3 changed files with 5,152 additions and 2,005 deletions.
diff --git a/index.js b/index.js
@@ -2,7 +2,15 @@
  * This is the entry point for the GraphQL API plugin. Here we specify the GraphQL schema and resolvers.
  */
 
-import {ApolloServer, gql} from 'apollo-server';
+import express from 'express';
+import cors from 'cors';
+import {ApolloServer, gql} from 'apollo-server-express';
+import {createServer} from 'http';
+import {execute, subscribe} from 'graphql';
+import {SubscriptionServer} from 'subscriptions-transport-ws';
+import {PubSub} from 'graphql-subscriptions';
+import {makeExecutableSchema} from '@graphql-tools/schema';
+
 
 /**
  * @typedef {Object} GraphQLConfig
@@ -14,14 +22,18 @@ import {ApolloServer, gql} from 'apollo-server';
  * @param {API} api
  * @param {GraphQLConfig} api.config.graphql The configuration object for the GraphQL API.
  */
-export function initialize(api) {
+export async function initialize(api) {
   const config = api.config.graphql ?? {};
+  const pubSub = new PubSub();
 
   if (config.disabled) {
     api.log.info('GraphQL API is disabled');
     return
   }
 
+  let id = 1
+  let messages = []
+
   const typeDefs = gql`
       type Query {
           agents: [Agent]
@@ -48,6 +60,10 @@ export function initialize(api) {
       type Mutation {
           sendMessage(message: String!): Message
       }
+
+      type Subscription {
+          messageSent: Message
+      }
   `;
 
   const resolvers = {
@@ -83,27 +99,66 @@ export function initialize(api) {
         return response.values()
       },
       messages: (parent, args, context) => {
-        return [
-          {id: 1, type: 'string', content: 'This is the first message'},
-          {id: 2, type: 'string', content: 'This is the second message'},
-          {id: 3, type: 'string', content: 'This is the third message'},
-          {id: 4, type: 'string', content: 'This is the fourth message'},
-          {id: 5, type: 'string', content: 'This is the fifth message'},
-        ]
+        return messages
       },
     },
     Mutation: {
       sendMessage: (parent, args, context) => {
         api.log.trace('GraphQL Received Message:', args)
-        return {id: 1, type: 'string', content: 'A message was sent: ' + args.message ?? ''}
+        const message = {id: id++, type: 'string', content: args.message ?? ''}
+        messages.push(message)
+        pubSub.publish('MESSAGE_SENT', {messageSent: message})
+        return message
+      },
+    },
+    Subscription: {
+      messageSent: {
+        subscribe: () => pubSub.asyncIterator(['MESSAGE_SENT']),
       },
     },
   };
 
-  const server = new ApolloServer({typeDefs, resolvers, context: {api}});
+  const schema = makeExecutableSchema({
+    typeDefs,
+    resolvers,
+  });
+
+  const app = express();
+
+  app.use(cors());
+
+  const apolloServer = new ApolloServer({
+    schema,
+    context: {api, pubsub: pubSub}, // Pass the PubSub instance to the context
+  });
+
   const port = config.port ?? 4000
-  server.listen(port).then(({url}) => {
-    api.log.info(`GraphQL API ready at`, url);
+
+  const httpServer = createServer(app);
+
+  await apolloServer.start()
+  apolloServer.applyMiddleware({app, path: '/graphql'});
+
+  httpServer.listen(port, () => {
+    console.log(`GraphQL Server ready at http://localhost:${port}${apolloServer.graphqlPath}`);
+    console.log(`GraphQL Subscriptions ready at ws://localhost:${port}${apolloServer.graphqlPath}`);
+  });
+
+  SubscriptionServer.create({
+    execute,
+    subscribe,
+    schema,
+  }, {
+    server: httpServer,
+    path: '/graphql',
   });
+
+  let randomId = 1;
+  setInterval(() => {
+    const message = {id: id++, type: 'string', content: `Random message ${randomId++}`};
+    messages.push(message);
+    console.log('Publishing message:', message);
+    pubSub.publish('MESSAGE_SENT', {messageSent: message});
+  }, 5000);
 }