👀 Views: 166 💬 Answers: 1 📅 Created: 2025-06-11

google-cloud-pubsub node.js message-queue JavaScript

I'm having trouble with I've been banging my head against this for hours... I'm working with a question with message ordering in Google Cloud Pub/Sub when using the Node.js SDK. I've set up a topic with two subscriptions and I'm trying to ensure that messages sent to the topic are processed in the same order by both subscriptions. However, I am seeing messages being delivered out of order when using the async subscription pull method. Here's a snippet of how I'm publishing messages: ```javascript const { PubSub } = require('@google-cloud/pubsub'); const pubsub = new PubSub(); async function publishMessages() { const topicName = 'my-topic'; const messages = ['msg1', 'msg2', 'msg3']; for (const message of messages) { const dataBuffer = Buffer.from(message); await pubsub.topic(topicName).publish(dataBuffer); console.log(`Message ${message} published.`); } } publishMessages(); ``` And here’s how I’m subscribing to those messages: ```javascript const subscriptionName = 'my-subscription'; const subscription = pubsub.subscription(subscriptionName); const messageHandler = message => { console.log(`Received message: ${message.data.toString()}`); message.ack(); }; subscription.on('message', messageHandler); ``` The scenario arises when I publish these messages in quick succession; I notice that they arrive at the subscriber out of order. I’ve also ensured that the delivery type for the subscriptions is set to `EXACTLY_ONCE`. I've read that configuring the `enableMessageOrdering` option might help, but I’m not sure how to implement it correctly. Could someone provide insights on how to ensure message ordering across multiple subscriptions? Any best practices or configuration settings I might be missing? I’m using the `@google-cloud/pubsub` version 2.9.0. I'm working on a web app that needs to handle this. Is there a better approach? Am I missing something obvious?