OpenTok Accelerator TextChat for JavaScript

The OpenTok Text Chat Accelerator Pack for JavaScript provides functionality you can add to your OpenTok applications that enables users to exchange text messages between mobile or browser-based devices.

Quick start

This section shows you how to use the accelerator pack.

Prerequisites

The dependencies for this library are listed in the package.json:

• jquery.
• kuende-livestamp.
• moment.
• opentok-solutions-logging.
• underscore.

Installation

Start by installing the dependencies:

$ npm install --save opentok-text-chat

Using a module bundler

If using a bundler like browserify or webpack:

const textChat = require('opentok-text-chat');

Without a module bundler

If you are not using a module bundler, include the accelerator pack in your html as well as the installed dependencies:

<script src="node_modules/opentok-text-chat/dist/opentok-text-chat.js"></script>
<script src="node_modules/opentok-solutions-logging/dist/opentok-solutions-logging.js"></script>
<script src="https://static.opentok.com/v2/js/opentok.min.js"></script>
<script src="your/path/to/underscore-min.js"></script>
<script src="your/path/to/jquery.min.js"></script>
<script src="your/path/to/moment.min.js"></script>
<script src="your/path/to/livestamp.min.js"></script>

Also, as our Sample Application demonstrates, you can specify some of the requirements to be sourced from cloudfare:

  <script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.17.1/moment.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/livestamp/1.1.2/livestamp.min.js"></script>

Usage

The text chat module will be available in global scope as TextChatAccPack

NOTE: Click here for a list of all OpenTok accelerator packs.

Exploring the code

The TextChatAccPack class in opentok-text-chat.js is the backbone of the text chat communication features for the app.

This class sets up the text chat UI views and events, and provides functions for sending, receiving, and rendering individual chat messages.

Initialization

The following options fields are used in the TextChatAccPack constructor:

Feature	Field
Set the session.	session
Set the id and name for the user.	sender
Set the chat container.	textChatContainer
Sets the position of the element that displays the information for the character count within the UI.	controlsContainer
Set the maximum message length.	limitCharacterMessage
Set the sender alias and the sender ID of the outgoing messages.	sender
Set the text chat container to automatically be displayed.	alwaysOpen
Custom message to display while waiting for other users to join.	waitingMessage

If you're using a bundler like webpack or Browserify, you can install the the text chat component with npm, and import into your application:

const TextChatAccPack = require('opentok-text-chat');
const textChat = new TextChatAccPack(options);

Otherwise, the package will need to be in global scope to be initialized:

const textChatOptions = {
 session: session,
 sender: {
   id: 'myCustomIdentifier',
   alias: 'David',
 },
 limitCharacterMessage: 160,
 controlsContainer: '#feedControls',
 textChatContainer: '#chatContainer',
 alwaysOpen: true
};

const textChat = new TextChatAccPack(textChatOptions);

TextChatAccPack Methods

The TextChat component defines the following methods:

Method	Description
showTextChat()	Show the text chat view.
hideTextChat()	Hide the text chat view.
isDisplayed()	Determines if the text chat accelerator pack is displayed.
isEnabled()	Determines if the text chat accelerator pack is enabled.
deliverUnsentMessages()	Deliver all prior messages to new participants.

For example, this line determines whether the text chat accelerator pack is displayed:

const displayed = textChat.isDisplayed();

Events

The TextChat component emits the following events:

Method	Description
messageReceived	A new message has been received.
messageSent	A new message has been sent.
errorSendingMessage	An error occurred when sending a message.

The following code shows how to subscribe to these events using opentok-accelerator-core:

otCore.on('messageReceived', event =>  . . .)
otCore.on('messageSent', event =>  . . .)
otCore.on('errorSendingMessage', error =>  . . .)

Sample Application

• Multiparty video communication sample app using the Accelerator TextChat with best-practices for Javascript.

Contribute

If you'd like to contribute to OpenTok Accelerator Pack development, please follow the guidelines in the contributing files.

License

This project is under the MIT License

About OpenTok

The OpenTok platform, developed by TokBox, makes it easy to embed high-quality interactive video, voice, messaging, and screen sharing into web and mobile apps. For more info on how OpenTok works, check out our Core Concepts.