chore: removed comments from pubsub module

packages/hoppscotch-backend/src/pubsub/pubsub.module.ts

@@ -0,0 +1,8 @@
+import { Module } from "@nestjs/common";
+import { PubSubService } from "./pubsub.service";
+
+@Module({
+  providers: [PubSubService],
+  exports: [PubSubService]
+})
+export class PubSubModule {}

packages/hoppscotch-backend/src/pubsub/pubsub.service.ts

@@ -0,0 +1,76 @@
+import { OnModuleInit } from '@nestjs/common';
+import { Injectable } from '@nestjs/common';
+import { default as Redis, RedisOptions } from 'ioredis';
+
+import { RedisPubSub } from 'graphql-redis-subscriptions';
+import { PubSub as LocalPubSub } from 'graphql-subscriptions';
+
+/**
+ * RedisPubSub uses JSON parsing for back and forth conversion, which loses Date objects, hence this reviver brings them back
+ * This function implementation should function like the JSON.parse reviver function
+ * @param key The key being parsed
+ * @param value The value being parsed
+ * @returns The updated value for the key
+ */
+const dateReviver = (key: string, value: unknown) => {
+  const isISO8601Z =
+    /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2}(?:\.\d*)?)Z$/;
+
+  if (typeof value === 'string' && isISO8601Z.test(value)) {
+    const tempDateNumber = Date.parse(value);
+
+    if (!isNaN(tempDateNumber)) {
+      return new Date(tempDateNumber);
+    }
+  }
+
+  return value;
+};
+
+/*
+ * Figure out which PubSub to use (simple/local for dev and Redis for production)
+ * and expose it
+ */
+
+@Injectable()
+export class PubSubService implements OnModuleInit {
+  private pubsub: RedisPubSub | LocalPubSub;
+
+  onModuleInit() {
+    if (process.env.PRODUCTION === 'false') {
+      console.log('Initialize PubSub in development mode');
+
+      this.pubsub = new LocalPubSub();
+    } else {
+      console.log('Initialize PubSub in production mode');
+      console.log(
+        `REDIS_IP: ${process.env.REDIS_IP}, REDIS_PORT: ${process.env.REDIS_PORT}`,
+      );
+
+      const redisOptions: RedisOptions = {
+        port: parseInt(process.env.REDIS_PORT || '6379'),
+        host: process.env.REDIS_IP,
+        retryStrategy: (times: number) => {
+          return Math.min(times * 50, 2000);
+        },
+      };
+
+      this.pubsub = new RedisPubSub({
+        publisher: new Redis(redisOptions),
+        subscriber: new Redis(redisOptions),
+        reviver: dateReviver,
+      });
+    }
+  }
+
+  asyncIterator<T>(
+    topic: string | string[],
+    options?: unknown,
+  ): AsyncIterator<T> {
+    return this.pubsub.asyncIterator(topic, options);
+  }
+
+  async publish(topic: string, payload: any) {
+    await this.pubsub.publish(topic, payload);
+  }
+}