nats

xk6-nats

This is a k6 extension using the xk6 system, that allows to use NATS protocol.

• xk6-nats
  • Build
  • API
    • Nats
    • Publishing
    • Subscribing
  • License

Build

To build a k6 binary with this extension, first ensure you have the prerequisites:

• Go toolchain
• Git

1. Install xk6 framework for extending k6:

go install go.k6.io/xk6/cmd/xk6@latest

1. Build the binary:

xk6 build --with github.com/Arten331/xk6-nats@latest

1. Run a test

k6 run -e NATS_HOSTNAME=localhost test/test.js

To run JetStream test, make sure NATS JetStream is started, e.g. nats-server -js

k6 run -e NATS_HOSTNAME=localhost test/test_jetstream.js

To run publish with headers test, make sure NATS JetStream is started, e.g. nats-server -js

./k6 run -e NATS_HOSTNAME=localhost test/test_headers.js

API

Nats

A Nats instance represents the connection with the NATS server. It's created with new Nats(configuration), where configuration is an object with the following attributes:

auth Configuration

The auth object allows you to specify how to authenticate with the NATS server. It has the following attributes:

Example Usage for Connection:

import { Nats } from 'k6/x/nats';

// Example: Basic connection with unsafe TLS
const natsConfigUnsafe = {
    servers: ['nats://localhost:4222'],
    auth: {
        unsafe: true,
        strategy: 'unsafe', // Explicitly declare 'unsafe' strategy
    },
};
const natsUnsafe = new Nats(natsConfigUnsafe);

// Example: Connection with username and password
const natsConfigUserPass = {
    servers: ['nats://localhost:4222'],
    auth: {
        strategy: 'user_password',
        username: 'myuser',
        password: 'mypassword',
    },
};
const natsUserPass = new Nats(natsConfigUserPass);

// Example: Connection with a token
const natsConfigToken = {
    servers: ['nats://localhost:4222'],
    auth: {
        strategy: 'token',
        token: 'mysecrettoken',
    },
};
const natsToken = new Nats(natsConfigToken);

Publishing

You can publish messages to a topic using the following functions:

Example:

const publisher = new Nats(natsConfig)

publisher.publish('topic', 'data')
publisher.publishWithHeaders('topic', 'data', { 'header1': 'value1' })
publisher.publishMsg({ topic: 'topic', data: 'string data', headers: { 'header1': 'value1' } })
publisher.publishMsg({ topic: 'topic', raw: [ 0, 1, 2, 3 ], headers: { 'header1': 'value1' } })
const message = publisher.request('topic', 'data', { 'header1': 'value1' })

Subscribing

You can subscribe to a topic using the following functions:

Example:

const subscriber = new Nats(natsConfig)
const subscription = subscriber.subscribe('topic', (msg) => {
    console.log(msg.data)
})
// ...
subscription.close()

Note: the subscription model has been changed. Now when you use subscribe method, a subscription object is returned and the subscription should be closed using the close() method.

License

The source code of this project is released under the MIT License.