Sukka

🧦 WebSocket testing made easy

Setup

Install Sukka and add it to your package.json file:

yarn add sukka --dev

Usage

Example WebSocket test using Jest:

const connect = require("sukka");

test("Login replies with a welcome message", () => {
  return connect("http://localhost:3000")
    .emit("login", "Foo")
    .expect("welcome", res => expect(res).toEqual("Bar"));
});

This test will:

1. Attempt to connect a WebSocket to localhost:3000.
2. Emit a single message with "login" as event name and "Foo" as the payload data.
3. Wait for a message to be received with "welcome" as event name.
4. Assert that the received message contains "Bar" as the payload data.

API

.emit(eventName[, ...args])

Emits an event to the endpoint with the provided name and arguments.

.expect(eventName[, handler])

Waits for a single event with the provided name. If a handler is provided, it will be called with the payload from the received message.

.end(callback)

Calls callback with an error as the first argument if some expectation failed. Use this to complete the test case and report the result back to your testing framework (typically done by passing the done handler as the callback).