@harelpls/use-pusher

@harelpls/use-pusher

Easy as React hooks that integrate with the pusher-js library.

• Install
• Hooks
• Usage
• useChannel
• usePresenceChannel
• useEvent
• useTrigger
• usePusher
• Trigger Server
• useClientTrigger
• Typescript
• Testing
• React Native
• Contributing
• License

API Reference/Docs

Install

yarn add @harelpls/use-pusher

Hooks

• useChannel
• usePresenceChannel
• useEvent
• useTrigger
• useClientTrigger
• usePusher

Usage

You must wrap your app with a PusherProvider and pass it config props for pusher-js initialisation.

import React from "react";
import { PusherProvider } from "@harelpls/use-pusher";

const config = {
  // required config props
  clientKey: "client-key",
  cluster: "ap4",

  // optional if you'd like to trigger events. BYO endpoint.
  // see "Trigger Server" below for more info
  triggerEndpoint: "/pusher/trigger",

  // required for private/presence channels
  // also sends auth headers to trigger endpoint
  authEndpoint: "/pusher/auth",
  auth: {
    headers: { Authorization: "Bearer token" },
  },
};

// Wrap app in provider
const App = () => {
  <PusherProvider {...config}>
    <Example />
  </PusherProvider>;
};

useChannel

Use this hook to subscribe to a channel.

// returns channel instance.
const channel = useChannel("channel-name");

usePresenceChannel

Augments a regular channel with member functionality.

const Example = () => {
  const { members, myID } = usePresenceChannel('presence-awesome');

  return (
    <ul>
      {Object.entries(members)
        // filter self from members
        .filter([id] => id !== myID)
        // map them to a list
        .map([id, info] => (
          <li key={id}>{info.name}</li>
        ))
      }
    </ul>
  )
}

useEvent

Bind to events on a channel with a callback.

const Example = () => {
  const [message, setMessages] = useState();
  const channel = useChannel("channel-name");
  useEvent(channel, "message", ({ data }) =>
    setMessages((messages) => [...messages, data])
  );
};

Note: This will bind and unbind to the event on each render. You may want to memoise your callback with useCallback before passing it in if you notice performance issues.

useTrigger

A helper function to create a server triggered event. BYO server (See Trigger Server below). Pass in triggerEndpoint prop to <PusherProvider />. Any auth headers from config.auth.headers automatically get passed to the fetch call.

import { useTrigger } from '@harelpls/use-pusher';

const Example = () => {.
  const trigger = useTrigger();
  const handleClick = () =>
    trigger("channel-name", "event-name", "hello");

  return (
    <button onClick={handleClick}>Say Hello</button>
  )
}

usePusher

Get access to the Pusher instance to do other things.

import { usePusher } from "@harelpls/use-pusher";

const Example = () => {
  const { client } = usePusher();
  client.log("Look ma, logs!");

  return null;
};

Trigger Server

In order to trigger an event, you'll have to create a simple lambda (or an express server if that's your thing). Below is a short lambda that can handle triggered events from useTrigger.

import Pusher from "pusher";

const pusher = new Pusher({
  appId: "app-id",
  key: "client-key",
  secret: "mad-secret",
  cluster: "ap4",
});

export async function handler(event) {
  const { channelName, eventName, data } = JSON.parse(event.body);
  pusher.trigger(channelName, eventName, data);
  return { statusCode: 200 };
}

useClientTrigger

I don't want a server though

I hear ya. If you're feeling audacious, you can use client events to push directly from the client:

import { useChannel, useClientTrigger } from "@harelpls/use-pusher";

const Example = () => {
  const channel = useChannel("presence-ca");
  const trigger = useClientTrigger(channel);
  const handleClientEvent = () => {
    trigger("Pew pew");
  };

  return <button onClick={handleClientEvent}>Fire</button>;
};

Typescript

This project was built using typescript, so types are built-in. Yeeeew!

Testing

I've teamed up with @nikolalsvk on pusher-js-mock to bring y'all a great pusher mock.

Testing emitted events with jest can be achieved using jest.mock and @testing-library/react (or enzyme, though your tests should reflect what the user should see NOT how the component handles events internally):

// Example.tsx
import React from "react";
import { useChannel, useEvent } from "@harelpls/use-pusher";

const Example = () => {
  const [title, setTitle] = useState();
  const channel = useChannel("my-channel");
  useEvent(channel, "title", ({ data }) => setTitle(data));

  return <span>{title}</span>;
};

// Example.test.tsx
import { render, act } from "@testing-library/react";
import { PusherMock, PusherChannelMock } from "pusher-js-mock";

// mock out the result of the useChannel hook
const mockChannel = new PusherChannelMock();
jest.mock("@harelpls/use-pusher", () => ({
  ...require.requireActual("@harelpls/use-pusher"),
  useChannel: () => mockChannel,
}));

test("should show a title when it receives a title event", async () => {
  // mock the client
  const client = new PusherMock("client-key", { cluster: "ap4" });

  // render component and provider with a mocked context value
  const { findByText } = render(
    <PusherProvider clientKey="client-key" cluster="ap4" value={{ client }}>
      <Example />
    </PusherProvider>
  );

  // emit an event on the mocked channel
  act(() => mockChannel.emit("title", { data: "Hello world" }));

  // assert expectations
  expect(await findByText("Hello world")).toBeInTheDocument();
});

Check out the example tests for testing presence channels.

React Native

This package comes with React Native support. Import your PusherProvider from @harelpls/use-pusher/react-native instead of the default @harelpls/use-pusher. All exports are re-exported from there.

Ensure you add the netinfo package to your project too: @react-native-community/netinfo.

import { PusherProvider, useChannel } from "@harelpls/use-pusher/react-native";

Contributing

1. Clone the repository and run yarn && yarn test:watch
2. Get coding!

Please write tests (100% jest coverage) and types.

License

MIT © @mayteio

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This hook is created using create-react-hook.

Changelog

v7.1.0

18 September 2020

• 🏷 add metadata type to useEvent (test missing, pending pusher-js-mock update) 7cc8563
• 📦 7.0.0 7ad36fb
• 😬 fix a regression where __PusherContext was no longer exposed by the package. 1fb5f43