Task and Message Queues with Multiple Providers
npm install qified





* Simple Message Queue for Processing Messages
* Simple Message Format Message
* Easily Send a Message publish()
* Easily Subscribe to a message Queue subscribe()
* Simple Task Format Task (Coming in v1.0.0)
* Easily Send a Task enqueue() (Coming in v1.0.0)
* Easily Subscribe to a Task Queue dequeue() (Coming in v1.0.0)
* Simple Acknowledge Acknowledge() in handler (Coming in v1.0.0)
* Async/Await Built In By Default
* Written in Typescript, Nodejs Last Two Versions, ESM and CJS
* Events and Hooks for all major actions via Hookified
* Customizable Serialize / Deserialize Handlers (Coming in v1.0.0)
* Customizable Compress / Decompress Handlers (Coming in v1.0.0)
* Provider Fail Over Support
``bash`
pnpm add qified
`js
import { Qified, MemoryMessageProvider } from 'qified';
// Create a new Qified instance with a memory provider
const qified = new Qified({
messageProviders: new MemoryMessageProvider()
});
// Subscribe to a topic
await qified.subscribe('notifications', {
id: 'notificationHandler',
handler: async (message) => {
console.log('Received:', message.data);
}
});
// Publish a message
await qified.publish('notifications', {
id: 'msg-1',
data: { text: 'Hello, World!' }
});
// Clean up
await qified.disconnect();
`
`js`
new Qified(options?: QifiedOptions)
Options:
- messageProviders?: MessageProvider | MessageProvider[] - a provider or Array of message providers to usetaskProviders?: TaskProvider[]
- - Array of task providers to use
Example:
`js
import { Qified, MemoryMessageProvider } from 'qified';
const qified = new Qified({
messageProviders: new MemoryMessageProvider()
});
`
Get or set the array of message providers. This property allows you to dynamically manage which message providers are active in your Qified instance.
Type: MessageProvider[]
Access: Read/Write
Description:
- Getter: Returns the current array of message providers being used
- Setter: Replaces all current message providers with a new array
Use Cases:
- Inspect which providers are currently configured
- Add or remove providers dynamically at runtime
- Replace all providers with a new set
- Migrate from one provider to another
Example:
`typescript
import { Qified, MemoryMessageProvider } from 'qified';
import { NatsMessageProvider } from '@qified/nats';
import { RedisMessageProvider } from '@qified/redis';
const qified = new Qified({
messageProviders: new MemoryMessageProvider()
});
// Get current providers
const providers = qified.messageProviders;
console.log(Currently using ${providers.length} provider(s));
// Add another provider
qified.messageProviders = [
new MemoryMessageProvider(),
new NatsMessageProvider()
];
// Replace all providers
qified.messageProviders = [
new RedisMessageProvider({ uri: 'redis://localhost:6379' })
];
// Access provider properties
qified.messageProviders.forEach(provider => {
console.log('Provider ID:', provider.id);
});
`
Important Notes:
- Setting this property does not automatically disconnect existing providers
- You should call disconnect() on old providers before replacing them to clean up resourcessubscribe
- All operations (, publish, unsubscribe) will execute across all providers in this array
Subscribe to a topic to receive messages. If multiple message providers are configured, this will subscribe on all of them.
Parameters:
- topic: string - The topic to subscribe tohandler: TopicHandler
- - Object containing an optional id and a handler function
Example:
`js`
await qified.subscribe('user-events', {
id: 'userEventHandler',
handler: async (message) => {
console.log('User event:', message.data);
}
});
Publish a message to a topic. If multiple message providers are configured, this will publish to all of them.
Parameters:
- topic: string - The topic to publish tomessage: Message
- - The message object to publish
Example:
`js`
await qified.publish('user-events', {
id: 'evt-123',
data: {
userId: 'user-456',
action: 'login',
timestamp: Date.now()
},
headers: {
'content-type': 'application/json'
}
});
Unsubscribe from a topic. If an id is provided, only that handler is unsubscribed. Otherwise, all handlers for the topic are unsubscribed.
Parameters:
- topic: string - The topic to unsubscribe fromid?: string
- - Optional handler ID. If not provided, all handlers are unsubscribed
Example:
`js
// Unsubscribe a specific handler
await qified.unsubscribe('user-events', 'userEventHandler');
// Unsubscribe all handlers for a topic
await qified.unsubscribe('user-events');
`
Disconnect from all providers and clean up resources.
Example:
``js`
await qified.disconnect();
Qified extends Hookified and emits events for all major operations. You can listen to these events to add custom logging, monitoring, or error handling.
The following events are available via the QifiedEvents enum:
- QifiedEvents.publish - Emitted after a message is successfully publishedQifiedEvents.subscribe
- - Emitted after successfully subscribing to a topicQifiedEvents.unsubscribe
- - Emitted after successfully unsubscribing from a topicQifiedEvents.disconnect
- - Emitted after successfully disconnecting from all providersQifiedEvents.error
- - Emitted when an error occurs during any operationQifiedEvents.info
- - Emitted for informational messagesQifiedEvents.warn
- - Emitted for warning messages
Use the on() method to listen to events:
`js
import { Qified, MemoryMessageProvider, QifiedEvents } from 'qified';
const qified = new Qified({
messageProviders: new MemoryMessageProvider()
});
// Listen for publish events
await qified.on(QifiedEvents.publish, async (data) => {
console.log('Message published to topic:', data.topic);
console.log('Message:', data.message);
});
// Listen for subscribe events
await qified.on(QifiedEvents.subscribe, async (data) => {
console.log('Subscribed to topic:', data.topic);
console.log('Handler ID:', data.handler.id);
});
// Listen for unsubscribe events
await qified.on(QifiedEvents.unsubscribe, async (data) => {
console.log('Unsubscribed from topic:', data.topic);
if (data.id) {
console.log('Handler ID:', data.id);
}
});
// Listen for disconnect events
await qified.on(QifiedEvents.disconnect, async () => {
console.log('Disconnected from all providers');
});
// Listen for errors
await qified.on(QifiedEvents.error, async (error) => {
console.error('Error occurred:', error);
});
// Now perform operations
await qified.subscribe('events', {
id: 'handler1',
handler: async (message) => {
console.log('Received:', message.data);
}
});
await qified.publish('events', {
id: 'msg-1',
data: { text: 'Hello!' }
});
await qified.unsubscribe('events', 'handler1');
await qified.disconnect();
`
Events provide a centralized way to handle errors across all operations:
`js
import { Qified, QifiedEvents } from 'qified';
import { NatsMessageProvider } from '@qified/nats';
const qified = new Qified({
messageProviders: new NatsMessageProvider()
});
// Centralized error handler
await qified.on(QifiedEvents.error, async (error) => {
console.error('Qified error:', error.message);
// Send to error tracking service
// Log to file
// Send alert
});
// Errors from publish, subscribe, etc. will be caught and emitted
await qified.publish('topic', { id: '1', data: { test: true } });
`
Qified provides before and after hooks for all major operations, allowing you to intercept and modify data before an operation executes, or perform actions after it completes. Hooks are powered by Hookified.
The following hooks are available via the QifiedHooks enum:
| Hook | Description | Context Properties |
|------|-------------|-------------------|
| beforeSubscribe | Called before subscribing to a topic | { topic, handler } |afterSubscribe
| | Called after subscribing to a topic | { topic, handler } |beforePublish
| | Called before publishing a message | { topic, message } |afterPublish
| | Called after publishing a message | { topic, message } |beforeUnsubscribe
| | Called before unsubscribing from a topic | { topic, id } |afterUnsubscribe
| | Called after unsubscribing from a topic | { topic, id } |beforeDisconnect
| | Called before disconnecting from providers | { providerCount } |afterDisconnect
| | Called after disconnecting from providers | { providerCount } |
Use the onHook() method to register a hook handler:
`js
import { Qified, MemoryMessageProvider, QifiedHooks } from 'qified';
const qified = new Qified({
messageProviders: new MemoryMessageProvider()
});
// Register a before hook
qified.onHook(QifiedHooks.beforePublish, async (context) => {
console.log('About to publish to:', context.topic);
});
// Register an after hook
qified.onHook(QifiedHooks.afterPublish, async (context) => {
console.log('Published message:', context.message.id);
});
`
Before hooks receive a mutable context object. Any changes you make to the context will be applied to the operation:
`js
import { Qified, MemoryMessageProvider, QifiedHooks } from 'qified';
const qified = new Qified({
messageProviders: new MemoryMessageProvider()
});
// Add timestamp and headers to all messages
qified.onHook(QifiedHooks.beforePublish, async (context) => {
// Add timestamp if not present
context.message.timestamp = context.message.timestamp ?? Date.now();
// Add custom headers
context.message.headers = {
...context.message.headers,
'x-processed-by': 'qified',
'x-environment': process.env.NODE_ENV
};
});
// Modify message data
qified.onHook(QifiedHooks.beforePublish, async (context) => {
// Add metadata to the message data
context.message.data = {
...context.message.data,
_meta: {
version: '1.0',
source: 'api'
}
};
});
// Subscribe to receive messages
await qified.subscribe('events', {
id: 'handler1',
handler: async (message) => {
// Message will have timestamp, headers, and modified data
console.log('Timestamp:', message.timestamp);
console.log('Headers:', message.headers);
console.log('Data:', message.data);
}
});
// Publish a message - hooks will modify it before sending
await qified.publish('events', {
id: 'msg-1',
data: { text: 'Hello!' }
});
`
You can also modify the topic in before hooks:
`jsproduction/${context.topic}
// Route all messages to a prefixed topic
qified.onHook(QifiedHooks.beforePublish, async (context) => {
context.topic = ;
});
// Subscribe to the prefixed topic
await qified.subscribe('production/events', {
id: 'handler1',
handler: async (message) => {
console.log('Received:', message.data);
}
});
// This publishes to 'production/events' due to the hook
await qified.publish('events', {
id: 'msg-1',
data: { text: 'Hello!' }
});
`
Multiple hooks for the same event execute in the order they were registered:
`js
// First hook - runs first
qified.onHook(QifiedHooks.beforePublish, async (context) => {
context.message.timestamp = Date.now();
});
// Second hook - runs second, can see changes from first hook
qified.onHook(QifiedHooks.beforePublish, async (context) => {
context.message.headers = { 'x-timestamp': String(context.message.timestamp) };
});
// Third hook - runs third
qified.onHook(QifiedHooks.beforePublish, async (context) => {
console.log('Final message:', context.message);
});
`
Both hooks and events are available, but they serve different purposes:
| Feature | Hooks | Events |
|---------|-------|--------|
| Timing | Before and after operations | After operations only |
| Data modification | Yes (before hooks) | No |
| Use case | Intercepting/transforming data | Logging, monitoring, side effects |
`js
// Hook - can modify the message before it's published
qified.onHook(QifiedHooks.beforePublish, async (context) => {
context.message.timestamp = Date.now();
});
// Event - notified after publish completes (cannot modify)
qified.on(QifiedEvents.publish, async (data) => {
console.log('Published:', data.message.id);
});
`
There are multiple providers available to use:
* Memory - this is built into the current qified library as MemoryMessageProvider.
* @qified/redis - Redis Provider
* @qified/rabbitmq - RabbitMQ Provider
* @qified/nats - NATS Provider
* @qified/zeromq - ZeroMQ Provider
Qified is written in TypeScript and tests are written in vitest. To run the tests, use the following command:
1. pnpm install - This will install all the dependenciespnpm test:services:start
2. - This will start the services needed for testing (Redis, RabbitMQ, etc)pnpm test` - This will run the tests
3.
To contribute follow the Contributing Guidelines and Code of Conduct.