MockStompBroker

A Node-based mock STOMP message broker with hooks for easy testing of your STOMP clients. Supports TypeScript.

Installing

npm install --save-dev mock-stomp-broker

Usage example

import MockStompBroker from "mock-stomp-broker";
import MyUpdateableTable from "./MyUpdateableTable";
 
describe("MyUpdateableTable", () => {
  it("should add rows to the table when row data is pushed via STOMP", async () => {
    const broker = new MockStompBroker();
    const rowData = {
      id: 1,
      name: "Jane Doe"
    };
    const wrapper = mount(
      <MyUpdateableTable websocketPort={broker.getPort()} rows={[]} />
    );
 
    expect(wrapper.text()).not.toContain(rowData.name);
 
    const [sessionId] = await broker.newSessionsConnected();
 
    await broker.subscribed(sessionId);
 
    const messageId = broker.scheduleMessage(`topics/my-topic`, rowData);
 
    await broker.messageSent(messageId);
 
    expect(wrapper.text()).toContain(rowData.name);
 
    broker.kill();
  });
 
  it("should clean up the websocket connection when table is unmounted", async () => {
    const broker = new MockStompBroker();
    const wrapper = mount(
      <MyUpdateableTable websocketPort={broker.getPort()} rows={[]} />
    );
 
    const [sessionId] = await broker.newSessionsConnected();
 
    wrapper.unmount();
 
    await broker.disconnected(sessionId);
 
    broker.kill();
  });
});

Config

The MockStompBroker can take a config object as a constructor arg. The config object and all its fields are optional.

Field	Default	Effect
port	N/A	Sets a specific port for the broker to start up on. Overrides portRange.
portRange	[8000, 9001]	When provided, the broker will choose a random port number in the provided range to start up on (useful when running multiple tests in parallel). Will only take effect if port is not provided.
endpoint	/websocket	Sets the websocket endpoint exposed by the broker. This is where your clients should connect.

Methods

Method	Args	Returns	Effect
getPort	N/A	number	Returns the broker's port. Use this to point your client(s) at the right port when generating random ports (either with portRange or the default behavior).
newSessionsConnected	N/A	Promise<string[]>	Resolves to an array of session IDs for sessions that were created since the last time you called this method. Rejects after 2000ms.
subscribed	string	Promise<void>	Resolves when a STOMP subscription has been established for the given session ID. Use this to ensure a session has an active subscription before trying to send messages. Rejects after 2000ms.
scheduleMessage	string, any, {}?	string	Schedule a STOMP message with a given payload to be asynchronously sent by the broker to all subscribers to a given topic. Can customize the message headers in the optional third argument. Returns a message ID for the scheduled message.
messageSent	string	Promise<void>	Resolves when a scheduled STOMP message with a given message ID has been sent by the broker. Use this to ensure message delivery to your clients before asserting on the outcome of receiving a message. Rejects after 2000ms.
disconnected	string	Promise<void>	Resolves when a session with a given session ID has disconnected. Use this to test your client cleanup logic. Rejects after 2000ms.
kill	N/A	void	Shut down the broker. You'll want to call this after every test case (or in an afterEach) to ensure your ports are cleaned up.