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Chat with PHP and Laravel

(warning)

Warning

As the Programmable Chat API is set to sunset in 2022, we will no longer maintain these chat tutorials.

Please see our Conversations API QuickStart to start building robust virtual spaces for conversation.

(error)

Danger

Programmable Chat has been deprecated and is no longer supported. Instead, we'll be focusing on the next generation of chat: Twilio Conversations. Find out more about the EOL process here.

If you're starting a new project, please visit the Conversations Docs to begin. If you've already built on Programmable Chat, please visit our Migration Guide to learn about how to switch.

Ready to implement a chat application using Twilio Programmable Chat Client?

This application allows users to exchange messages through different channels, using the Twilio Programmable Chat API. On this example, we'll show how to use this API features to manage channels and to show it's usages.

Properati built a web and mobile messaging app to help real estate buyers and sellers connect in real-time. Learn more here.

For your convenience, we consolidated the source code for this tutorial in a single GitHub repository. Feel free to clone it and tweak it as required.

Token Generation

In order to create a Twilio Programmable Chat client, you will need an access token. This token holds information about your Twilio Account and Programmable Chat API keys.

We generate this token by creating a new AccessToken and providing it with a ChatGrant. The new AccessToken object is created using your Twilio credentials.

With Laravel we must create a provider that will inject the AccessToken object in the controller, the same goes for ChatMessagingGrant inside TwilioChatGrantProvider.php. We'll see how to use these objects in the next step.

Generate an Access Token

app/Providers/TwilioAccessTokenProvider.php


_32<?php
_32namespace App\Providers;
_32use Illuminate\Support\ServiceProvider;
_32use Twilio\Jwt\AccessToken;
_32
_32class TwilioAccessTokenProvider extends ServiceProvider
_32{
_32    /**
_32     * Register the application services.
_32     *
_32     * @return void
_32     */
_32    public function register()
_32    {
_32        $this->app->bind(
_32            AccessToken::class, function ($app) {
_32                $TWILIO_ACCOUNT_SID = config('services.twilio')['accountSid'];
_32                $TWILIO_API_KEY = config('services.twilio')['apiKey'];
_32                $TWILIO_API_SECRET = config('services.twilio')['apiSecret'];
_32
_32                $token = new AccessToken(
_32                    $TWILIO_ACCOUNT_SID,
_32                    $TWILIO_API_KEY,
_32                    $TWILIO_API_SECRET,
_32                    3600
_32                );
_32
_32                return $token;
_32            }
_32        );
_32    }
_32}

We can generate a token, now we need a way for the chat app to get it.

Token Generation Controller

On our controller, we expose the endpoint responsible for providing a valid token using this parameter:

identity : identifies the user itself

Once we have used the AccessToken object to generate a token we can use the AccessToken's method token.toJWT() to get the token as a String. Then we just return the token as a JSON encoded string.

Token Generation Controller

app/Http/Controllers/TokenController.php


_31<?php
_31namespace App\Http\Controllers;
_31use Illuminate\Http\Request;
_31use App\Http\Requests;
_31use App\Http\Controllers\Controller;
_31use Twilio\Jwt\AccessToken;
_31use Twilio\Jwt\Grants\ChatGrant;
_31
_31class TokenController extends Controller
_31{
_31    public function generate(Request $request, AccessToken $accessToken, ChatGrant $chatGrant)
_31    {
_31        $appName = "TwilioChat";
_31        $identity = $request->input("identity");
_31
_31        $TWILIO_CHAT_SERVICE_SID = config('services.twilio')['chatServiceSid'];
_31
_31        $accessToken->setIdentity($identity);
_31
_31        $chatGrant->setServiceSid($TWILIO_CHAT_SERVICE_SID);
_31
_31        $accessToken->addGrant($chatGrant);
_31
_31        $response = array(
_31            'identity' => $identity,
_31            'token' => $accessToken->toJWT()
_31        );
_31
_31        return response()->json($response);
_31    }
_31}

Now that we have a route that generates JWT tokens on demand, let's use this route to initialize our Twilio Chat Client.

Initializing the Programmable Chat Client

Our client fetches a new Token by making a POST request to our endpoint.

With the token we can create a new Twilio.AccessManager, and initialize our Twilio.Chat.Client.

Initialize the Chat Client

public/js/twiliochat.js


_361var twiliochat = (function() {
_361  var tc = {};
_361
_361  var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_361  var GENERAL_CHANNEL_NAME = 'General Channel';
_361  var MESSAGES_HISTORY_LIMIT = 50;
_361
_361  var $channelList;
_361  var $inputText;
_361  var $usernameInput;
_361  var $statusRow;
_361  var $connectPanel;
_361  var $newChannelInputRow;
_361  var $newChannelInput;
_361  var $typingRow;
_361  var $typingPlaceholder;
_361
_361  $(document).ready(function() {
_361    tc.$messageList = $('#message-list');
_361    $channelList = $('#channel-list');
_361    $inputText = $('#input-text');
_361    $usernameInput = $('#username-input');
_361    $statusRow = $('#status-row');
_361    $connectPanel = $('#connect-panel');
_361    $newChannelInputRow = $('#new-channel-input-row');
_361    $newChannelInput = $('#new-channel-input');
_361    $typingRow = $('#typing-row');
_361    $typingPlaceholder = $('#typing-placeholder');
_361    $usernameInput.focus();
_361    $usernameInput.on('keypress', handleUsernameInputKeypress);
_361    $inputText.on('keypress', handleInputTextKeypress);
_361    $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_361    $('#connect-image').on('click', connectClientWithUsername);
_361    $('#add-channel-image').on('click', showAddChannelInput);
_361    $('#leave-span').on('click', disconnectClient);
_361    $('#delete-channel-span').on('click', deleteCurrentChannel);
_361  });
_361
_361  function handleUsernameInputKeypress(event) {
_361    if (event.keyCode === 13){
_361      connectClientWithUsername();
_361    }
_361  }
_361
_361  function handleInputTextKeypress(event) {
_361    if (event.keyCode === 13) {
_361      tc.currentChannel.sendMessage($(this).val());
_361      event.preventDefault();
_361      $(this).val('');
_361    }
_361    else {
_361      notifyTyping();
_361    }
_361  }
_361
_361  var notifyTyping = $.throttle(function() {
_361    tc.currentChannel.typing();
_361  }, 1000);
_361
_361  tc.handleNewChannelInputKeypress = function(event) {
_361    if (event.keyCode === 13) {
_361      tc.messagingClient.createChannel({
_361        friendlyName: $newChannelInput.val()
_361      }).then(hideAddChannelInput);
_361      $(this).val('');
_361      event.preventDefault();
_361    }
_361  };
_361
_361  function connectClientWithUsername() {
_361    var usernameText = $usernameInput.val();
_361    $usernameInput.val('');
_361    if (usernameText == '') {
_361      alert('Username cannot be empty');
_361      return;
_361    }
_361    tc.username = usernameText;
_361    fetchAccessToken(tc.username, connectMessagingClient);
_361  }
_361
_361  function fetchAccessToken(username, handler) {
_361    $.post('/token', {identity: username}, null, 'json')
_361      .done(function(response) {
_361        handler(response.token);
_361      })
_361      .fail(function(error) {
_361        console.log('Failed to fetch the Access Token with error: ' + error);
_361      });
_361  }
_361
_361  function connectMessagingClient(token) {
_361    // Initialize the Chat messaging client
_361    tc.accessManager = new Twilio.AccessManager(token);
_361    Twilio.Chat.Client.create(token).then(function(client) {
_361      tc.messagingClient = client;
_361      updateConnectedUI();
_361      tc.loadChannelList(tc.joinGeneralChannel);
_361      tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('tokenExpired', refreshToken);
_361    });
_361  }
_361
_361  function refreshToken() {
_361    fetchAccessToken(tc.username, setNewToken);
_361  }
_361
_361  function setNewToken(tokenResponse) {
_361    tc.accessManager.updateToken(tokenResponse.token);
_361  }
_361
_361  function updateConnectedUI() {
_361    $('#username-span').text(tc.username);
_361    $statusRow.addClass('connected').removeClass('disconnected');
_361    tc.$messageList.addClass('connected').removeClass('disconnected');
_361    $connectPanel.addClass('connected').removeClass('disconnected');
_361    $inputText.addClass('with-shadow');
_361    $typingRow.addClass('connected').removeClass('disconnected');
_361  }
_361
_361  tc.loadChannelList = function(handler) {
_361    if (tc.messagingClient === undefined) {
_361      console.log('Client is not initialized');
_361      return;
_361    }
_361
_361    tc.messagingClient.getPublicChannelDescriptors().then(function(channels) {
_361      tc.channelArray = tc.sortChannelsByName(channels.items);
_361      $channelList.text('');
_361      tc.channelArray.forEach(addChannel);
_361      if (typeof handler === 'function') {
_361        handler();
_361      }
_361    });
_361  };
_361
_361  tc.joinGeneralChannel = function() {
_361    console.log('Attempting to join "general" chat channel...');
_361    if (!tc.generalChannel) {
_361      // If it doesn't exist, let's create it
_361      tc.messagingClient.createChannel({
_361        uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_361        friendlyName: GENERAL_CHANNEL_NAME
_361      }).then(function(channel) {
_361        console.log('Created general channel');
_361        tc.generalChannel = channel;
_361        tc.loadChannelList(tc.joinGeneralChannel);
_361      });
_361    }
_361    else {
_361      console.log('Found general channel:');
_361      setupChannel(tc.generalChannel);
_361    }
_361  };
_361
_361  function initChannel(channel) {
_361    console.log('Initialized channel ' + channel.friendlyName);
_361    return tc.messagingClient.getChannelBySid(channel.sid);
_361  }
_361
_361  function joinChannel(_channel) {
_361    return _channel.join()
_361      .then(function(joinedChannel) {
_361        console.log('Joined channel ' + joinedChannel.friendlyName);
_361        updateChannelUI(_channel);
_361        tc.currentChannel = _channel;
_361        tc.loadMessages();
_361        return joinedChannel;
_361      });
_361  }
_361
_361  function initChannelEvents() {
_361    console.log(tc.currentChannel.friendlyName + ' ready.');
_361    tc.currentChannel.on('messageAdded', tc.addMessageToList);
_361    tc.currentChannel.on('typingStarted', showTypingStarted);
_361    tc.currentChannel.on('typingEnded', hideTypingStarted);
_361    tc.currentChannel.on('memberJoined', notifyMemberJoined);
_361    tc.currentChannel.on('memberLeft', notifyMemberLeft);
_361    $inputText.prop('disabled', false).focus();
_361  }
_361
_361  function setupChannel(channel) {
_361    return leaveCurrentChannel()
_361      .then(function() {
_361        return initChannel(channel);
_361      })
_361      .then(function(_channel) {
_361        return joinChannel(_channel);
_361      })
_361      .then(initChannelEvents);
_361  }
_361
_361  tc.loadMessages = function() {
_361    tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_361      messages.items.forEach(tc.addMessageToList);
_361    });
_361  };
_361
_361  function leaveCurrentChannel() {
_361    if (tc.currentChannel) {
_361      return tc.currentChannel.leave().then(function(leftChannel) {
_361        console.log('left ' + leftChannel.friendlyName);
_361        leftChannel.removeListener('messageAdded', tc.addMessageToList);
_361        leftChannel.removeListener('typingStarted', showTypingStarted);
_361        leftChannel.removeListener('typingEnded', hideTypingStarted);
_361        leftChannel.removeListener('memberJoined', notifyMemberJoined);
_361        leftChannel.removeListener('memberLeft', notifyMemberLeft);
_361      });
_361    } else {
_361      return Promise.resolve();
_361    }
_361  }
_361
_361  tc.addMessageToList = function(message) {
_361    var rowDiv = $('<div>').addClass('row no-margin');
_361    rowDiv.loadTemplate($('#message-template'), {
_361      username: message.author,
_361      date: dateFormatter.getTodayDate(message.dateCreated),
_361      body: message.body
_361    });
_361    if (message.author === tc.username) {
_361      rowDiv.addClass('own-message');
_361    }
_361
_361    tc.$messageList.append(rowDiv);
_361    scrollToMessageListBottom();
_361  };
_361
_361  function notifyMemberJoined(member) {
_361    notify(member.identity + ' joined the channel')
_361  }
_361
_361  function notifyMemberLeft(member) {
_361    notify(member.identity + ' left the channel');
_361  }
_361
_361  function notify(message) {
_361    var row = $('<div>').addClass('col-md-12');
_361    row.loadTemplate('#member-notification-template', {
_361      status: message
_361    });
_361    tc.$messageList.append(row);
_361    scrollToMessageListBottom();
_361  }
_361
_361  function showTypingStarted(member) {
_361    $typingPlaceholder.text(member.identity + ' is typing...');
_361  }
_361
_361  function hideTypingStarted(member) {
_361    $typingPlaceholder.text('');
_361  }
_361
_361  function scrollToMessageListBottom() {
_361    tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_361  }
_361
_361  function updateChannelUI(selectedChannel) {
_361    var channelElements = $('.channel-element').toArray();
_361    var channelElement = channelElements.filter(function(element) {
_361      return $(element).data().sid === selectedChannel.sid;
_361    });
_361    channelElement = $(channelElement);
_361    if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.currentChannelContainer = channelElement;
_361    }
_361    tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_361    channelElement.removeClass('unselected-channel').addClass('selected-channel');
_361    tc.currentChannelContainer = channelElement;
_361  }
_361
_361  function showAddChannelInput() {
_361    if (tc.messagingClient) {
_361      $newChannelInputRow.addClass('showing').removeClass('not-showing');
_361      $channelList.addClass('showing').removeClass('not-showing');
_361      $newChannelInput.focus();
_361    }
_361  }
_361
_361  function hideAddChannelInput() {
_361    $newChannelInputRow.addClass('not-showing').removeClass('showing');
_361    $channelList.addClass('not-showing').removeClass('showing');
_361    $newChannelInput.val('');
_361  }
_361
_361  function addChannel(channel) {
_361    if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.generalChannel = channel;
_361    }
_361    var rowDiv = $('<div>').addClass('row channel-row');
_361    rowDiv.loadTemplate('#channel-template', {
_361      channelName: channel.friendlyName
_361    });
_361
_361    var channelP = rowDiv.children().children().first();
_361
_361    rowDiv.on('click', selectChannel);
_361    channelP.data('sid', channel.sid);
_361    if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_361      tc.currentChannelContainer = channelP;
_361      channelP.addClass('selected-channel');
_361    }
_361    else {
_361      channelP.addClass('unselected-channel')
_361    }
_361
_361    $channelList.append(rowDiv);
_361  }
_361
_361  function deleteCurrentChannel() {
_361    if (!tc.currentChannel) {
_361      return;
_361    }
_361    if (tc.currentChannel.sid === tc.generalChannel.sid) {
_361      alert('You cannot delete the general channel');
_361      return;
_361    }
_361    tc.currentChannel.delete().then(function(channel) {
_361      console.log('channel: '+ channel.friendlyName + ' deleted');
_361      setupChannel(tc.generalChannel);
_361    });
_361  }
_361
_361  function selectChannel(event) {
_361    var target = $(event.target);
_361    var channelSid = target.data().sid;
_361    var selectedChannel = tc.channelArray.filter(function(channel) {
_361      return channel.sid === channelSid;
_361    })[0];
_361    if (selectedChannel === tc.currentChannel) {
_361      return;
_361    }
_361    setupChannel(selectedChannel);
_361  };
_361
_361  function disconnectClient() {
_361    leaveCurrentChannel();
_361    $channelList.text('');
_361    tc.$messageList.text('');
_361    channels = undefined;
_361    $statusRow.addClass('disconnected').removeClass('connected');
_361    tc.$messageList.addClass('disconnected').removeClass('connected');
_361    $connectPanel.addClass('disconnected').removeClass('connected');
_361    $inputText.removeClass('with-shadow');
_361    $typingRow.addClass('disconnected').removeClass('connected');
_361  }
_361
_361  tc.sortChannelsByName = function(channels) {
_361    return channels.sort(function(a, b) {
_361      if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return -1;
_361      }
_361      if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return 1;
_361      }
_361      return a.friendlyName.localeCompare(b.friendlyName);
_361    });
_361  };
_361
_361  return tc;
_361})();

Now that we've initialized our Chat Client, let's see how we can get a list of channels.

Getting the Channel List

After initializing the client we can call the getPublicChannelDescriptors method to retrieve all visible channels. This method returns a promise which we use to show the list of channels retrieved on the UI.

Get the Channel List

public/js/twiliochat.js


_361var twiliochat = (function() {
_361  var tc = {};
_361
_361  var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_361  var GENERAL_CHANNEL_NAME = 'General Channel';
_361  var MESSAGES_HISTORY_LIMIT = 50;
_361
_361  var $channelList;
_361  var $inputText;
_361  var $usernameInput;
_361  var $statusRow;
_361  var $connectPanel;
_361  var $newChannelInputRow;
_361  var $newChannelInput;
_361  var $typingRow;
_361  var $typingPlaceholder;
_361
_361  $(document).ready(function() {
_361    tc.$messageList = $('#message-list');
_361    $channelList = $('#channel-list');
_361    $inputText = $('#input-text');
_361    $usernameInput = $('#username-input');
_361    $statusRow = $('#status-row');
_361    $connectPanel = $('#connect-panel');
_361    $newChannelInputRow = $('#new-channel-input-row');
_361    $newChannelInput = $('#new-channel-input');
_361    $typingRow = $('#typing-row');
_361    $typingPlaceholder = $('#typing-placeholder');
_361    $usernameInput.focus();
_361    $usernameInput.on('keypress', handleUsernameInputKeypress);
_361    $inputText.on('keypress', handleInputTextKeypress);
_361    $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_361    $('#connect-image').on('click', connectClientWithUsername);
_361    $('#add-channel-image').on('click', showAddChannelInput);
_361    $('#leave-span').on('click', disconnectClient);
_361    $('#delete-channel-span').on('click', deleteCurrentChannel);
_361  });
_361
_361  function handleUsernameInputKeypress(event) {
_361    if (event.keyCode === 13){
_361      connectClientWithUsername();
_361    }
_361  }
_361
_361  function handleInputTextKeypress(event) {
_361    if (event.keyCode === 13) {
_361      tc.currentChannel.sendMessage($(this).val());
_361      event.preventDefault();
_361      $(this).val('');
_361    }
_361    else {
_361      notifyTyping();
_361    }
_361  }
_361
_361  var notifyTyping = $.throttle(function() {
_361    tc.currentChannel.typing();
_361  }, 1000);
_361
_361  tc.handleNewChannelInputKeypress = function(event) {
_361    if (event.keyCode === 13) {
_361      tc.messagingClient.createChannel({
_361        friendlyName: $newChannelInput.val()
_361      }).then(hideAddChannelInput);
_361      $(this).val('');
_361      event.preventDefault();
_361    }
_361  };
_361
_361  function connectClientWithUsername() {
_361    var usernameText = $usernameInput.val();
_361    $usernameInput.val('');
_361    if (usernameText == '') {
_361      alert('Username cannot be empty');
_361      return;
_361    }
_361    tc.username = usernameText;
_361    fetchAccessToken(tc.username, connectMessagingClient);
_361  }
_361
_361  function fetchAccessToken(username, handler) {
_361    $.post('/token', {identity: username}, null, 'json')
_361      .done(function(response) {
_361        handler(response.token);
_361      })
_361      .fail(function(error) {
_361        console.log('Failed to fetch the Access Token with error: ' + error);
_361      });
_361  }
_361
_361  function connectMessagingClient(token) {
_361    // Initialize the Chat messaging client
_361    tc.accessManager = new Twilio.AccessManager(token);
_361    Twilio.Chat.Client.create(token).then(function(client) {
_361      tc.messagingClient = client;
_361      updateConnectedUI();
_361      tc.loadChannelList(tc.joinGeneralChannel);
_361      tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('tokenExpired', refreshToken);
_361    });
_361  }
_361
_361  function refreshToken() {
_361    fetchAccessToken(tc.username, setNewToken);
_361  }
_361
_361  function setNewToken(tokenResponse) {
_361    tc.accessManager.updateToken(tokenResponse.token);
_361  }
_361
_361  function updateConnectedUI() {
_361    $('#username-span').text(tc.username);
_361    $statusRow.addClass('connected').removeClass('disconnected');
_361    tc.$messageList.addClass('connected').removeClass('disconnected');
_361    $connectPanel.addClass('connected').removeClass('disconnected');
_361    $inputText.addClass('with-shadow');
_361    $typingRow.addClass('connected').removeClass('disconnected');
_361  }
_361
_361  tc.loadChannelList = function(handler) {
_361    if (tc.messagingClient === undefined) {
_361      console.log('Client is not initialized');
_361      return;
_361    }
_361
_361    tc.messagingClient.getPublicChannelDescriptors().then(function(channels) {
_361      tc.channelArray = tc.sortChannelsByName(channels.items);
_361      $channelList.text('');
_361      tc.channelArray.forEach(addChannel);
_361      if (typeof handler === 'function') {
_361        handler();
_361      }
_361    });
_361  };
_361
_361  tc.joinGeneralChannel = function() {
_361    console.log('Attempting to join "general" chat channel...');
_361    if (!tc.generalChannel) {
_361      // If it doesn't exist, let's create it
_361      tc.messagingClient.createChannel({
_361        uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_361        friendlyName: GENERAL_CHANNEL_NAME
_361      }).then(function(channel) {
_361        console.log('Created general channel');
_361        tc.generalChannel = channel;
_361        tc.loadChannelList(tc.joinGeneralChannel);
_361      });
_361    }
_361    else {
_361      console.log('Found general channel:');
_361      setupChannel(tc.generalChannel);
_361    }
_361  };
_361
_361  function initChannel(channel) {
_361    console.log('Initialized channel ' + channel.friendlyName);
_361    return tc.messagingClient.getChannelBySid(channel.sid);
_361  }
_361
_361  function joinChannel(_channel) {
_361    return _channel.join()
_361      .then(function(joinedChannel) {
_361        console.log('Joined channel ' + joinedChannel.friendlyName);
_361        updateChannelUI(_channel);
_361        tc.currentChannel = _channel;
_361        tc.loadMessages();
_361        return joinedChannel;
_361      });
_361  }
_361
_361  function initChannelEvents() {
_361    console.log(tc.currentChannel.friendlyName + ' ready.');
_361    tc.currentChannel.on('messageAdded', tc.addMessageToList);
_361    tc.currentChannel.on('typingStarted', showTypingStarted);
_361    tc.currentChannel.on('typingEnded', hideTypingStarted);
_361    tc.currentChannel.on('memberJoined', notifyMemberJoined);
_361    tc.currentChannel.on('memberLeft', notifyMemberLeft);
_361    $inputText.prop('disabled', false).focus();
_361  }
_361
_361  function setupChannel(channel) {
_361    return leaveCurrentChannel()
_361      .then(function() {
_361        return initChannel(channel);
_361      })
_361      .then(function(_channel) {
_361        return joinChannel(_channel);
_361      })
_361      .then(initChannelEvents);
_361  }
_361
_361  tc.loadMessages = function() {
_361    tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_361      messages.items.forEach(tc.addMessageToList);
_361    });
_361  };
_361
_361  function leaveCurrentChannel() {
_361    if (tc.currentChannel) {
_361      return tc.currentChannel.leave().then(function(leftChannel) {
_361        console.log('left ' + leftChannel.friendlyName);
_361        leftChannel.removeListener('messageAdded', tc.addMessageToList);
_361        leftChannel.removeListener('typingStarted', showTypingStarted);
_361        leftChannel.removeListener('typingEnded', hideTypingStarted);
_361        leftChannel.removeListener('memberJoined', notifyMemberJoined);
_361        leftChannel.removeListener('memberLeft', notifyMemberLeft);
_361      });
_361    } else {
_361      return Promise.resolve();
_361    }
_361  }
_361
_361  tc.addMessageToList = function(message) {
_361    var rowDiv = $('<div>').addClass('row no-margin');
_361    rowDiv.loadTemplate($('#message-template'), {
_361      username: message.author,
_361      date: dateFormatter.getTodayDate(message.dateCreated),
_361      body: message.body
_361    });
_361    if (message.author === tc.username) {
_361      rowDiv.addClass('own-message');
_361    }
_361
_361    tc.$messageList.append(rowDiv);
_361    scrollToMessageListBottom();
_361  };
_361
_361  function notifyMemberJoined(member) {
_361    notify(member.identity + ' joined the channel')
_361  }
_361
_361  function notifyMemberLeft(member) {
_361    notify(member.identity + ' left the channel');
_361  }
_361
_361  function notify(message) {
_361    var row = $('<div>').addClass('col-md-12');
_361    row.loadTemplate('#member-notification-template', {
_361      status: message
_361    });
_361    tc.$messageList.append(row);
_361    scrollToMessageListBottom();
_361  }
_361
_361  function showTypingStarted(member) {
_361    $typingPlaceholder.text(member.identity + ' is typing...');
_361  }
_361
_361  function hideTypingStarted(member) {
_361    $typingPlaceholder.text('');
_361  }
_361
_361  function scrollToMessageListBottom() {
_361    tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_361  }
_361
_361  function updateChannelUI(selectedChannel) {
_361    var channelElements = $('.channel-element').toArray();
_361    var channelElement = channelElements.filter(function(element) {
_361      return $(element).data().sid === selectedChannel.sid;
_361    });
_361    channelElement = $(channelElement);
_361    if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.currentChannelContainer = channelElement;
_361    }
_361    tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_361    channelElement.removeClass('unselected-channel').addClass('selected-channel');
_361    tc.currentChannelContainer = channelElement;
_361  }
_361
_361  function showAddChannelInput() {
_361    if (tc.messagingClient) {
_361      $newChannelInputRow.addClass('showing').removeClass('not-showing');
_361      $channelList.addClass('showing').removeClass('not-showing');
_361      $newChannelInput.focus();
_361    }
_361  }
_361
_361  function hideAddChannelInput() {
_361    $newChannelInputRow.addClass('not-showing').removeClass('showing');
_361    $channelList.addClass('not-showing').removeClass('showing');
_361    $newChannelInput.val('');
_361  }
_361
_361  function addChannel(channel) {
_361    if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.generalChannel = channel;
_361    }
_361    var rowDiv = $('<div>').addClass('row channel-row');
_361    rowDiv.loadTemplate('#channel-template', {
_361      channelName: channel.friendlyName
_361    });
_361
_361    var channelP = rowDiv.children().children().first();
_361
_361    rowDiv.on('click', selectChannel);
_361    channelP.data('sid', channel.sid);
_361    if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_361      tc.currentChannelContainer = channelP;
_361      channelP.addClass('selected-channel');
_361    }
_361    else {
_361      channelP.addClass('unselected-channel')
_361    }
_361
_361    $channelList.append(rowDiv);
_361  }
_361
_361  function deleteCurrentChannel() {
_361    if (!tc.currentChannel) {
_361      return;
_361    }
_361    if (tc.currentChannel.sid === tc.generalChannel.sid) {
_361      alert('You cannot delete the general channel');
_361      return;
_361    }
_361    tc.currentChannel.delete().then(function(channel) {
_361      console.log('channel: '+ channel.friendlyName + ' deleted');
_361      setupChannel(tc.generalChannel);
_361    });
_361  }
_361
_361  function selectChannel(event) {
_361    var target = $(event.target);
_361    var channelSid = target.data().sid;
_361    var selectedChannel = tc.channelArray.filter(function(channel) {
_361      return channel.sid === channelSid;
_361    })[0];
_361    if (selectedChannel === tc.currentChannel) {
_361      return;
_361    }
_361    setupChannel(selectedChannel);
_361  };
_361
_361  function disconnectClient() {
_361    leaveCurrentChannel();
_361    $channelList.text('');
_361    tc.$messageList.text('');
_361    channels = undefined;
_361    $statusRow.addClass('disconnected').removeClass('connected');
_361    tc.$messageList.addClass('disconnected').removeClass('connected');
_361    $connectPanel.addClass('disconnected').removeClass('connected');
_361    $inputText.removeClass('with-shadow');
_361    $typingRow.addClass('disconnected').removeClass('connected');
_361  }
_361
_361  tc.sortChannelsByName = function(channels) {
_361    return channels.sort(function(a, b) {
_361      if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return -1;
_361      }
_361      if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return 1;
_361      }
_361      return a.friendlyName.localeCompare(b.friendlyName);
_361    });
_361  };
_361
_361  return tc;
_361})();

Next, we need a default channel.

Join the General Channel

This application will try to join a channel called "General Channel" when it starts. If the channel doesn't exist, we'll create one with that name. The scope of this example application will show you how to work only with public channels, but the Programmable Chat client allows you to create private channels and handle invitations.

Notice: we set a unique name for the general channel since we don't want to create a new general channel every time we start the application.

Join the General Channel

public/js/twiliochat.js


_361var twiliochat = (function() {
_361  var tc = {};
_361
_361  var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_361  var GENERAL_CHANNEL_NAME = 'General Channel';
_361  var MESSAGES_HISTORY_LIMIT = 50;
_361
_361  var $channelList;
_361  var $inputText;
_361  var $usernameInput;
_361  var $statusRow;
_361  var $connectPanel;
_361  var $newChannelInputRow;
_361  var $newChannelInput;
_361  var $typingRow;
_361  var $typingPlaceholder;
_361
_361  $(document).ready(function() {
_361    tc.$messageList = $('#message-list');
_361    $channelList = $('#channel-list');
_361    $inputText = $('#input-text');
_361    $usernameInput = $('#username-input');
_361    $statusRow = $('#status-row');
_361    $connectPanel = $('#connect-panel');
_361    $newChannelInputRow = $('#new-channel-input-row');
_361    $newChannelInput = $('#new-channel-input');
_361    $typingRow = $('#typing-row');
_361    $typingPlaceholder = $('#typing-placeholder');
_361    $usernameInput.focus();
_361    $usernameInput.on('keypress', handleUsernameInputKeypress);
_361    $inputText.on('keypress', handleInputTextKeypress);
_361    $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_361    $('#connect-image').on('click', connectClientWithUsername);
_361    $('#add-channel-image').on('click', showAddChannelInput);
_361    $('#leave-span').on('click', disconnectClient);
_361    $('#delete-channel-span').on('click', deleteCurrentChannel);
_361  });
_361
_361  function handleUsernameInputKeypress(event) {
_361    if (event.keyCode === 13){
_361      connectClientWithUsername();
_361    }
_361  }
_361
_361  function handleInputTextKeypress(event) {
_361    if (event.keyCode === 13) {
_361      tc.currentChannel.sendMessage($(this).val());
_361      event.preventDefault();
_361      $(this).val('');
_361    }
_361    else {
_361      notifyTyping();
_361    }
_361  }
_361
_361  var notifyTyping = $.throttle(function() {
_361    tc.currentChannel.typing();
_361  }, 1000);
_361
_361  tc.handleNewChannelInputKeypress = function(event) {
_361    if (event.keyCode === 13) {
_361      tc.messagingClient.createChannel({
_361        friendlyName: $newChannelInput.val()
_361      }).then(hideAddChannelInput);
_361      $(this).val('');
_361      event.preventDefault();
_361    }
_361  };
_361
_361  function connectClientWithUsername() {
_361    var usernameText = $usernameInput.val();
_361    $usernameInput.val('');
_361    if (usernameText == '') {
_361      alert('Username cannot be empty');
_361      return;
_361    }
_361    tc.username = usernameText;
_361    fetchAccessToken(tc.username, connectMessagingClient);
_361  }
_361
_361  function fetchAccessToken(username, handler) {
_361    $.post('/token', {identity: username}, null, 'json')
_361      .done(function(response) {
_361        handler(response.token);
_361      })
_361      .fail(function(error) {
_361        console.log('Failed to fetch the Access Token with error: ' + error);
_361      });
_361  }
_361
_361  function connectMessagingClient(token) {
_361    // Initialize the Chat messaging client
_361    tc.accessManager = new Twilio.AccessManager(token);
_361    Twilio.Chat.Client.create(token).then(function(client) {
_361      tc.messagingClient = client;
_361      updateConnectedUI();
_361      tc.loadChannelList(tc.joinGeneralChannel);
_361      tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('tokenExpired', refreshToken);
_361    });
_361  }
_361
_361  function refreshToken() {
_361    fetchAccessToken(tc.username, setNewToken);
_361  }
_361
_361  function setNewToken(tokenResponse) {
_361    tc.accessManager.updateToken(tokenResponse.token);
_361  }
_361
_361  function updateConnectedUI() {
_361    $('#username-span').text(tc.username);
_361    $statusRow.addClass('connected').removeClass('disconnected');
_361    tc.$messageList.addClass('connected').removeClass('disconnected');
_361    $connectPanel.addClass('connected').removeClass('disconnected');
_361    $inputText.addClass('with-shadow');
_361    $typingRow.addClass('connected').removeClass('disconnected');
_361  }
_361
_361  tc.loadChannelList = function(handler) {
_361    if (tc.messagingClient === undefined) {
_361      console.log('Client is not initialized');
_361      return;
_361    }
_361
_361    tc.messagingClient.getPublicChannelDescriptors().then(function(channels) {
_361      tc.channelArray = tc.sortChannelsByName(channels.items);
_361      $channelList.text('');
_361      tc.channelArray.forEach(addChannel);
_361      if (typeof handler === 'function') {
_361        handler();
_361      }
_361    });
_361  };
_361
_361  tc.joinGeneralChannel = function() {
_361    console.log('Attempting to join "general" chat channel...');
_361    if (!tc.generalChannel) {
_361      // If it doesn't exist, let's create it
_361      tc.messagingClient.createChannel({
_361        uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_361        friendlyName: GENERAL_CHANNEL_NAME
_361      }).then(function(channel) {
_361        console.log('Created general channel');
_361        tc.generalChannel = channel;
_361        tc.loadChannelList(tc.joinGeneralChannel);
_361      });
_361    }
_361    else {
_361      console.log('Found general channel:');
_361      setupChannel(tc.generalChannel);
_361    }
_361  };
_361
_361  function initChannel(channel) {
_361    console.log('Initialized channel ' + channel.friendlyName);
_361    return tc.messagingClient.getChannelBySid(channel.sid);
_361  }
_361
_361  function joinChannel(_channel) {
_361    return _channel.join()
_361      .then(function(joinedChannel) {
_361        console.log('Joined channel ' + joinedChannel.friendlyName);
_361        updateChannelUI(_channel);
_361        tc.currentChannel = _channel;
_361        tc.loadMessages();
_361        return joinedChannel;
_361      });
_361  }
_361
_361  function initChannelEvents() {
_361    console.log(tc.currentChannel.friendlyName + ' ready.');
_361    tc.currentChannel.on('messageAdded', tc.addMessageToList);
_361    tc.currentChannel.on('typingStarted', showTypingStarted);
_361    tc.currentChannel.on('typingEnded', hideTypingStarted);
_361    tc.currentChannel.on('memberJoined', notifyMemberJoined);
_361    tc.currentChannel.on('memberLeft', notifyMemberLeft);
_361    $inputText.prop('disabled', false).focus();
_361  }
_361
_361  function setupChannel(channel) {
_361    return leaveCurrentChannel()
_361      .then(function() {
_361        return initChannel(channel);
_361      })
_361      .then(function(_channel) {
_361        return joinChannel(_channel);
_361      })
_361      .then(initChannelEvents);
_361  }
_361
_361  tc.loadMessages = function() {
_361    tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_361      messages.items.forEach(tc.addMessageToList);
_361    });
_361  };
_361
_361  function leaveCurrentChannel() {
_361    if (tc.currentChannel) {
_361      return tc.currentChannel.leave().then(function(leftChannel) {
_361        console.log('left ' + leftChannel.friendlyName);
_361        leftChannel.removeListener('messageAdded', tc.addMessageToList);
_361        leftChannel.removeListener('typingStarted', showTypingStarted);
_361        leftChannel.removeListener('typingEnded', hideTypingStarted);
_361        leftChannel.removeListener('memberJoined', notifyMemberJoined);
_361        leftChannel.removeListener('memberLeft', notifyMemberLeft);
_361      });
_361    } else {
_361      return Promise.resolve();
_361    }
_361  }
_361
_361  tc.addMessageToList = function(message) {
_361    var rowDiv = $('<div>').addClass('row no-margin');
_361    rowDiv.loadTemplate($('#message-template'), {
_361      username: message.author,
_361      date: dateFormatter.getTodayDate(message.dateCreated),
_361      body: message.body
_361    });
_361    if (message.author === tc.username) {
_361      rowDiv.addClass('own-message');
_361    }
_361
_361    tc.$messageList.append(rowDiv);
_361    scrollToMessageListBottom();
_361  };
_361
_361  function notifyMemberJoined(member) {
_361    notify(member.identity + ' joined the channel')
_361  }
_361
_361  function notifyMemberLeft(member) {
_361    notify(member.identity + ' left the channel');
_361  }
_361
_361  function notify(message) {
_361    var row = $('<div>').addClass('col-md-12');
_361    row.loadTemplate('#member-notification-template', {
_361      status: message
_361    });
_361    tc.$messageList.append(row);
_361    scrollToMessageListBottom();
_361  }
_361
_361  function showTypingStarted(member) {
_361    $typingPlaceholder.text(member.identity + ' is typing...');
_361  }
_361
_361  function hideTypingStarted(member) {
_361    $typingPlaceholder.text('');
_361  }
_361
_361  function scrollToMessageListBottom() {
_361    tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_361  }
_361
_361  function updateChannelUI(selectedChannel) {
_361    var channelElements = $('.channel-element').toArray();
_361    var channelElement = channelElements.filter(function(element) {
_361      return $(element).data().sid === selectedChannel.sid;
_361    });
_361    channelElement = $(channelElement);
_361    if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.currentChannelContainer = channelElement;
_361    }
_361    tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_361    channelElement.removeClass('unselected-channel').addClass('selected-channel');
_361    tc.currentChannelContainer = channelElement;
_361  }
_361
_361  function showAddChannelInput() {
_361    if (tc.messagingClient) {
_361      $newChannelInputRow.addClass('showing').removeClass('not-showing');
_361      $channelList.addClass('showing').removeClass('not-showing');
_361      $newChannelInput.focus();
_361    }
_361  }
_361
_361  function hideAddChannelInput() {
_361    $newChannelInputRow.addClass('not-showing').removeClass('showing');
_361    $channelList.addClass('not-showing').removeClass('showing');
_361    $newChannelInput.val('');
_361  }
_361
_361  function addChannel(channel) {
_361    if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.generalChannel = channel;
_361    }
_361    var rowDiv = $('<div>').addClass('row channel-row');
_361    rowDiv.loadTemplate('#channel-template', {
_361      channelName: channel.friendlyName
_361    });
_361
_361    var channelP = rowDiv.children().children().first();
_361
_361    rowDiv.on('click', selectChannel);
_361    channelP.data('sid', channel.sid);
_361    if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_361      tc.currentChannelContainer = channelP;
_361      channelP.addClass('selected-channel');
_361    }
_361    else {
_361      channelP.addClass('unselected-channel')
_361    }
_361
_361    $channelList.append(rowDiv);
_361  }
_361
_361  function deleteCurrentChannel() {
_361    if (!tc.currentChannel) {
_361      return;
_361    }
_361    if (tc.currentChannel.sid === tc.generalChannel.sid) {
_361      alert('You cannot delete the general channel');
_361      return;
_361    }
_361    tc.currentChannel.delete().then(function(channel) {
_361      console.log('channel: '+ channel.friendlyName + ' deleted');
_361      setupChannel(tc.generalChannel);
_361    });
_361  }
_361
_361  function selectChannel(event) {
_361    var target = $(event.target);
_361    var channelSid = target.data().sid;
_361    var selectedChannel = tc.channelArray.filter(function(channel) {
_361      return channel.sid === channelSid;
_361    })[0];
_361    if (selectedChannel === tc.currentChannel) {
_361      return;
_361    }
_361    setupChannel(selectedChannel);
_361  };
_361
_361  function disconnectClient() {
_361    leaveCurrentChannel();
_361    $channelList.text('');
_361    tc.$messageList.text('');
_361    channels = undefined;
_361    $statusRow.addClass('disconnected').removeClass('connected');
_361    tc.$messageList.addClass('disconnected').removeClass('connected');
_361    $connectPanel.addClass('disconnected').removeClass('connected');
_361    $inputText.removeClass('with-shadow');
_361    $typingRow.addClass('disconnected').removeClass('connected');
_361  }
_361
_361  tc.sortChannelsByName = function(channels) {
_361    return channels.sort(function(a, b) {
_361      if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return -1;
_361      }
_361      if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return 1;
_361      }
_361      return a.friendlyName.localeCompare(b.friendlyName);
_361    });
_361  };
_361
_361  return tc;
_361})();

Now let's listen for some channel events.

Listen to Channel Events

Next, we listen for channel events. In our case we're setting listeners to the following events:

messageAdded : When another member sends a message to the channel you are connected to.
typingStarted : When another member is typing a message on the channel that you are connected to.
typingEnded : When another member stops typing a message on the channel that you are connected to.
memberJoined : When another member joins the channel that you are connected to.
memberLeft : When another member leaves the channel that you are connected to.

We register a different function to handle each particular event.

Listen to Channel Events

public/js/twiliochat.js


_361var twiliochat = (function() {
_361  var tc = {};
_361
_361  var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_361  var GENERAL_CHANNEL_NAME = 'General Channel';
_361  var MESSAGES_HISTORY_LIMIT = 50;
_361
_361  var $channelList;
_361  var $inputText;
_361  var $usernameInput;
_361  var $statusRow;
_361  var $connectPanel;
_361  var $newChannelInputRow;
_361  var $newChannelInput;
_361  var $typingRow;
_361  var $typingPlaceholder;
_361
_361  $(document).ready(function() {
_361    tc.$messageList = $('#message-list');
_361    $channelList = $('#channel-list');
_361    $inputText = $('#input-text');
_361    $usernameInput = $('#username-input');
_361    $statusRow = $('#status-row');
_361    $connectPanel = $('#connect-panel');
_361    $newChannelInputRow = $('#new-channel-input-row');
_361    $newChannelInput = $('#new-channel-input');
_361    $typingRow = $('#typing-row');
_361    $typingPlaceholder = $('#typing-placeholder');
_361    $usernameInput.focus();
_361    $usernameInput.on('keypress', handleUsernameInputKeypress);
_361    $inputText.on('keypress', handleInputTextKeypress);
_361    $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_361    $('#connect-image').on('click', connectClientWithUsername);
_361    $('#add-channel-image').on('click', showAddChannelInput);
_361    $('#leave-span').on('click', disconnectClient);
_361    $('#delete-channel-span').on('click', deleteCurrentChannel);
_361  });
_361
_361  function handleUsernameInputKeypress(event) {
_361    if (event.keyCode === 13){
_361      connectClientWithUsername();
_361    }
_361  }
_361
_361  function handleInputTextKeypress(event) {
_361    if (event.keyCode === 13) {
_361      tc.currentChannel.sendMessage($(this).val());
_361      event.preventDefault();
_361      $(this).val('');
_361    }
_361    else {
_361      notifyTyping();
_361    }
_361  }
_361
_361  var notifyTyping = $.throttle(function() {
_361    tc.currentChannel.typing();
_361  }, 1000);
_361
_361  tc.handleNewChannelInputKeypress = function(event) {
_361    if (event.keyCode === 13) {
_361      tc.messagingClient.createChannel({
_361        friendlyName: $newChannelInput.val()
_361      }).then(hideAddChannelInput);
_361      $(this).val('');
_361      event.preventDefault();
_361    }
_361  };
_361
_361  function connectClientWithUsername() {
_361    var usernameText = $usernameInput.val();
_361    $usernameInput.val('');
_361    if (usernameText == '') {
_361      alert('Username cannot be empty');
_361      return;
_361    }
_361    tc.username = usernameText;
_361    fetchAccessToken(tc.username, connectMessagingClient);
_361  }
_361
_361  function fetchAccessToken(username, handler) {
_361    $.post('/token', {identity: username}, null, 'json')
_361      .done(function(response) {
_361        handler(response.token);
_361      })
_361      .fail(function(error) {
_361        console.log('Failed to fetch the Access Token with error: ' + error);
_361      });
_361  }
_361
_361  function connectMessagingClient(token) {
_361    // Initialize the Chat messaging client
_361    tc.accessManager = new Twilio.AccessManager(token);
_361    Twilio.Chat.Client.create(token).then(function(client) {
_361      tc.messagingClient = client;
_361      updateConnectedUI();
_361      tc.loadChannelList(tc.joinGeneralChannel);
_361      tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('tokenExpired', refreshToken);
_361    });
_361  }
_361
_361  function refreshToken() {
_361    fetchAccessToken(tc.username, setNewToken);
_361  }
_361
_361  function setNewToken(tokenResponse) {
_361    tc.accessManager.updateToken(tokenResponse.token);
_361  }
_361
_361  function updateConnectedUI() {
_361    $('#username-span').text(tc.username);
_361    $statusRow.addClass('connected').removeClass('disconnected');
_361    tc.$messageList.addClass('connected').removeClass('disconnected');
_361    $connectPanel.addClass('connected').removeClass('disconnected');
_361    $inputText.addClass('with-shadow');
_361    $typingRow.addClass('connected').removeClass('disconnected');
_361  }
_361
_361  tc.loadChannelList = function(handler) {
_361    if (tc.messagingClient === undefined) {
_361      console.log('Client is not initialized');
_361      return;
_361    }
_361
_361    tc.messagingClient.getPublicChannelDescriptors().then(function(channels) {
_361      tc.channelArray = tc.sortChannelsByName(channels.items);
_361      $channelList.text('');
_361      tc.channelArray.forEach(addChannel);
_361      if (typeof handler === 'function') {
_361        handler();
_361      }
_361    });
_361  };
_361
_361  tc.joinGeneralChannel = function() {
_361    console.log('Attempting to join "general" chat channel...');
_361    if (!tc.generalChannel) {
_361      // If it doesn't exist, let's create it
_361      tc.messagingClient.createChannel({
_361        uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_361        friendlyName: GENERAL_CHANNEL_NAME
_361      }).then(function(channel) {
_361        console.log('Created general channel');
_361        tc.generalChannel = channel;
_361        tc.loadChannelList(tc.joinGeneralChannel);
_361      });
_361    }
_361    else {
_361      console.log('Found general channel:');
_361      setupChannel(tc.generalChannel);
_361    }
_361  };
_361
_361  function initChannel(channel) {
_361    console.log('Initialized channel ' + channel.friendlyName);
_361    return tc.messagingClient.getChannelBySid(channel.sid);
_361  }
_361
_361  function joinChannel(_channel) {
_361    return _channel.join()
_361      .then(function(joinedChannel) {
_361        console.log('Joined channel ' + joinedChannel.friendlyName);
_361        updateChannelUI(_channel);
_361        tc.currentChannel = _channel;
_361        tc.loadMessages();
_361        return joinedChannel;
_361      });
_361  }
_361
_361  function initChannelEvents() {
_361    console.log(tc.currentChannel.friendlyName + ' ready.');
_361    tc.currentChannel.on('messageAdded', tc.addMessageToList);
_361    tc.currentChannel.on('typingStarted', showTypingStarted);
_361    tc.currentChannel.on('typingEnded', hideTypingStarted);
_361    tc.currentChannel.on('memberJoined', notifyMemberJoined);
_361    tc.currentChannel.on('memberLeft', notifyMemberLeft);
_361    $inputText.prop('disabled', false).focus();
_361  }
_361
_361  function setupChannel(channel) {
_361    return leaveCurrentChannel()
_361      .then(function() {
_361        return initChannel(channel);
_361      })
_361      .then(function(_channel) {
_361        return joinChannel(_channel);
_361      })
_361      .then(initChannelEvents);
_361  }
_361
_361  tc.loadMessages = function() {
_361    tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_361      messages.items.forEach(tc.addMessageToList);
_361    });
_361  };
_361
_361  function leaveCurrentChannel() {
_361    if (tc.currentChannel) {
_361      return tc.currentChannel.leave().then(function(leftChannel) {
_361        console.log('left ' + leftChannel.friendlyName);
_361        leftChannel.removeListener('messageAdded', tc.addMessageToList);
_361        leftChannel.removeListener('typingStarted', showTypingStarted);
_361        leftChannel.removeListener('typingEnded', hideTypingStarted);
_361        leftChannel.removeListener('memberJoined', notifyMemberJoined);
_361        leftChannel.removeListener('memberLeft', notifyMemberLeft);
_361      });
_361    } else {
_361      return Promise.resolve();
_361    }
_361  }
_361
_361  tc.addMessageToList = function(message) {
_361    var rowDiv = $('<div>').addClass('row no-margin');
_361    rowDiv.loadTemplate($('#message-template'), {
_361      username: message.author,
_361      date: dateFormatter.getTodayDate(message.dateCreated),
_361      body: message.body
_361    });
_361    if (message.author === tc.username) {
_361      rowDiv.addClass('own-message');
_361    }
_361
_361    tc.$messageList.append(rowDiv);
_361    scrollToMessageListBottom();
_361  };
_361
_361  function notifyMemberJoined(member) {
_361    notify(member.identity + ' joined the channel')
_361  }
_361
_361  function notifyMemberLeft(member) {
_361    notify(member.identity + ' left the channel');
_361  }
_361
_361  function notify(message) {
_361    var row = $('<div>').addClass('col-md-12');
_361    row.loadTemplate('#member-notification-template', {
_361      status: message
_361    });
_361    tc.$messageList.append(row);
_361    scrollToMessageListBottom();
_361  }
_361
_361  function showTypingStarted(member) {
_361    $typingPlaceholder.text(member.identity + ' is typing...');
_361  }
_361
_361  function hideTypingStarted(member) {
_361    $typingPlaceholder.text('');
_361  }
_361
_361  function scrollToMessageListBottom() {
_361    tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_361  }
_361
_361  function updateChannelUI(selectedChannel) {
_361    var channelElements = $('.channel-element').toArray();
_361    var channelElement = channelElements.filter(function(element) {
_361      return $(element).data().sid === selectedChannel.sid;
_361    });
_361    channelElement = $(channelElement);
_361    if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.currentChannelContainer = channelElement;
_361    }
_361    tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_361    channelElement.removeClass('unselected-channel').addClass('selected-channel');
_361    tc.currentChannelContainer = channelElement;
_361  }
_361
_361  function showAddChannelInput() {
_361    if (tc.messagingClient) {
_361      $newChannelInputRow.addClass('showing').removeClass('not-showing');
_361      $channelList.addClass('showing').removeClass('not-showing');
_361      $newChannelInput.focus();
_361    }
_361  }
_361
_361  function hideAddChannelInput() {
_361    $newChannelInputRow.addClass('not-showing').removeClass('showing');
_361    $channelList.addClass('not-showing').removeClass('showing');
_361    $newChannelInput.val('');
_361  }
_361
_361  function addChannel(channel) {
_361    if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.generalChannel = channel;
_361    }
_361    var rowDiv = $('<div>').addClass('row channel-row');
_361    rowDiv.loadTemplate('#channel-template', {
_361      channelName: channel.friendlyName
_361    });
_361
_361    var channelP = rowDiv.children().children().first();
_361
_361    rowDiv.on('click', selectChannel);
_361    channelP.data('sid', channel.sid);
_361    if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_361      tc.currentChannelContainer = channelP;
_361      channelP.addClass('selected-channel');
_361    }
_361    else {
_361      channelP.addClass('unselected-channel')
_361    }
_361
_361    $channelList.append(rowDiv);
_361  }
_361
_361  function deleteCurrentChannel() {
_361    if (!tc.currentChannel) {
_361      return;
_361    }
_361    if (tc.currentChannel.sid === tc.generalChannel.sid) {
_361      alert('You cannot delete the general channel');
_361      return;
_361    }
_361    tc.currentChannel.delete().then(function(channel) {
_361      console.log('channel: '+ channel.friendlyName + ' deleted');
_361      setupChannel(tc.generalChannel);
_361    });
_361  }
_361
_361  function selectChannel(event) {
_361    var target = $(event.target);
_361    var channelSid = target.data().sid;
_361    var selectedChannel = tc.channelArray.filter(function(channel) {
_361      return channel.sid === channelSid;
_361    })[0];
_361    if (selectedChannel === tc.currentChannel) {
_361      return;
_361    }
_361    setupChannel(selectedChannel);
_361  };
_361
_361  function disconnectClient() {
_361    leaveCurrentChannel();
_361    $channelList.text('');
_361    tc.$messageList.text('');
_361    channels = undefined;
_361    $statusRow.addClass('disconnected').removeClass('connected');
_361    tc.$messageList.addClass('disconnected').removeClass('connected');
_361    $connectPanel.addClass('disconnected').removeClass('connected');
_361    $inputText.removeClass('with-shadow');
_361    $typingRow.addClass('disconnected').removeClass('connected');
_361  }
_361
_361  tc.sortChannelsByName = function(channels) {
_361    return channels.sort(function(a, b) {
_361      if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return -1;
_361      }
_361      if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return 1;
_361      }
_361      return a.friendlyName.localeCompare(b.friendlyName);
_361    });
_361  };
_361
_361  return tc;
_361})();

The client emits events as well. Let's see how we can listen to those events as well.

Listen to Client Events

Just like with channels, we can register handlers for events on the Client:

channelAdded : When a channel becomes visible to the Client.
channelRemoved : When a channel is no longer visible to the Client.
tokenExpired : When the supplied token expires.

Listen to Client Events

public/js/twiliochat.js


_361var twiliochat = (function() {
_361  var tc = {};
_361
_361  var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_361  var GENERAL_CHANNEL_NAME = 'General Channel';
_361  var MESSAGES_HISTORY_LIMIT = 50;
_361
_361  var $channelList;
_361  var $inputText;
_361  var $usernameInput;
_361  var $statusRow;
_361  var $connectPanel;
_361  var $newChannelInputRow;
_361  var $newChannelInput;
_361  var $typingRow;
_361  var $typingPlaceholder;
_361
_361  $(document).ready(function() {
_361    tc.$messageList = $('#message-list');
_361    $channelList = $('#channel-list');
_361    $inputText = $('#input-text');
_361    $usernameInput = $('#username-input');
_361    $statusRow = $('#status-row');
_361    $connectPanel = $('#connect-panel');
_361    $newChannelInputRow = $('#new-channel-input-row');
_361    $newChannelInput = $('#new-channel-input');
_361    $typingRow = $('#typing-row');
_361    $typingPlaceholder = $('#typing-placeholder');
_361    $usernameInput.focus();
_361    $usernameInput.on('keypress', handleUsernameInputKeypress);
_361    $inputText.on('keypress', handleInputTextKeypress);
_361    $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_361    $('#connect-image').on('click', connectClientWithUsername);
_361    $('#add-channel-image').on('click', showAddChannelInput);
_361    $('#leave-span').on('click', disconnectClient);
_361    $('#delete-channel-span').on('click', deleteCurrentChannel);
_361  });
_361
_361  function handleUsernameInputKeypress(event) {
_361    if (event.keyCode === 13){
_361      connectClientWithUsername();
_361    }
_361  }
_361
_361  function handleInputTextKeypress(event) {
_361    if (event.keyCode === 13) {
_361      tc.currentChannel.sendMessage($(this).val());
_361      event.preventDefault();
_361      $(this).val('');
_361    }
_361    else {
_361      notifyTyping();
_361    }
_361  }
_361
_361  var notifyTyping = $.throttle(function() {
_361    tc.currentChannel.typing();
_361  }, 1000);
_361
_361  tc.handleNewChannelInputKeypress = function(event) {
_361    if (event.keyCode === 13) {
_361      tc.messagingClient.createChannel({
_361        friendlyName: $newChannelInput.val()
_361      }).then(hideAddChannelInput);
_361      $(this).val('');
_361      event.preventDefault();
_361    }
_361  };
_361
_361  function connectClientWithUsername() {
_361    var usernameText = $usernameInput.val();
_361    $usernameInput.val('');
_361    if (usernameText == '') {
_361      alert('Username cannot be empty');
_361      return;
_361    }
_361    tc.username = usernameText;
_361    fetchAccessToken(tc.username, connectMessagingClient);
_361  }
_361
_361  function fetchAccessToken(username, handler) {
_361    $.post('/token', {identity: username}, null, 'json')
_361      .done(function(response) {
_361        handler(response.token);
_361      })
_361      .fail(function(error) {
_361        console.log('Failed to fetch the Access Token with error: ' + error);
_361      });
_361  }
_361
_361  function connectMessagingClient(token) {
_361    // Initialize the Chat messaging client
_361    tc.accessManager = new Twilio.AccessManager(token);
_361    Twilio.Chat.Client.create(token).then(function(client) {
_361      tc.messagingClient = client;
_361      updateConnectedUI();
_361      tc.loadChannelList(tc.joinGeneralChannel);
_361      tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('tokenExpired', refreshToken);
_361    });
_361  }
_361
_361  function refreshToken() {
_361    fetchAccessToken(tc.username, setNewToken);
_361  }
_361
_361  function setNewToken(tokenResponse) {
_361    tc.accessManager.updateToken(tokenResponse.token);
_361  }
_361
_361  function updateConnectedUI() {
_361    $('#username-span').text(tc.username);
_361    $statusRow.addClass('connected').removeClass('disconnected');
_361    tc.$messageList.addClass('connected').removeClass('disconnected');
_361    $connectPanel.addClass('connected').removeClass('disconnected');
_361    $inputText.addClass('with-shadow');
_361    $typingRow.addClass('connected').removeClass('disconnected');
_361  }
_361
_361  tc.loadChannelList = function(handler) {
_361    if (tc.messagingClient === undefined) {
_361      console.log('Client is not initialized');
_361      return;
_361    }
_361
_361    tc.messagingClient.getPublicChannelDescriptors().then(function(channels) {
_361      tc.channelArray = tc.sortChannelsByName(channels.items);
_361      $channelList.text('');
_361      tc.channelArray.forEach(addChannel);
_361      if (typeof handler === 'function') {
_361        handler();
_361      }
_361    });
_361  };
_361
_361  tc.joinGeneralChannel = function() {
_361    console.log('Attempting to join "general" chat channel...');
_361    if (!tc.generalChannel) {
_361      // If it doesn't exist, let's create it
_361      tc.messagingClient.createChannel({
_361        uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_361        friendlyName: GENERAL_CHANNEL_NAME
_361      }).then(function(channel) {
_361        console.log('Created general channel');
_361        tc.generalChannel = channel;
_361        tc.loadChannelList(tc.joinGeneralChannel);
_361      });
_361    }
_361    else {
_361      console.log('Found general channel:');
_361      setupChannel(tc.generalChannel);
_361    }
_361  };
_361
_361  function initChannel(channel) {
_361    console.log('Initialized channel ' + channel.friendlyName);
_361    return tc.messagingClient.getChannelBySid(channel.sid);
_361  }
_361
_361  function joinChannel(_channel) {
_361    return _channel.join()
_361      .then(function(joinedChannel) {
_361        console.log('Joined channel ' + joinedChannel.friendlyName);
_361        updateChannelUI(_channel);
_361        tc.currentChannel = _channel;
_361        tc.loadMessages();
_361        return joinedChannel;
_361      });
_361  }
_361
_361  function initChannelEvents() {
_361    console.log(tc.currentChannel.friendlyName + ' ready.');
_361    tc.currentChannel.on('messageAdded', tc.addMessageToList);
_361    tc.currentChannel.on('typingStarted', showTypingStarted);
_361    tc.currentChannel.on('typingEnded', hideTypingStarted);
_361    tc.currentChannel.on('memberJoined', notifyMemberJoined);
_361    tc.currentChannel.on('memberLeft', notifyMemberLeft);
_361    $inputText.prop('disabled', false).focus();
_361  }
_361
_361  function setupChannel(channel) {
_361    return leaveCurrentChannel()
_361      .then(function() {
_361        return initChannel(channel);
_361      })
_361      .then(function(_channel) {
_361        return joinChannel(_channel);
_361      })
_361      .then(initChannelEvents);
_361  }
_361
_361  tc.loadMessages = function() {
_361    tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_361      messages.items.forEach(tc.addMessageToList);
_361    });
_361  };
_361
_361  function leaveCurrentChannel() {
_361    if (tc.currentChannel) {
_361      return tc.currentChannel.leave().then(function(leftChannel) {
_361        console.log('left ' + leftChannel.friendlyName);
_361        leftChannel.removeListener('messageAdded', tc.addMessageToList);
_361        leftChannel.removeListener('typingStarted', showTypingStarted);
_361        leftChannel.removeListener('typingEnded', hideTypingStarted);
_361        leftChannel.removeListener('memberJoined', notifyMemberJoined);
_361        leftChannel.removeListener('memberLeft', notifyMemberLeft);
_361      });
_361    } else {
_361      return Promise.resolve();
_361    }
_361  }
_361
_361  tc.addMessageToList = function(message) {
_361    var rowDiv = $('<div>').addClass('row no-margin');
_361    rowDiv.loadTemplate($('#message-template'), {
_361      username: message.author,
_361      date: dateFormatter.getTodayDate(message.dateCreated),
_361      body: message.body
_361    });
_361    if (message.author === tc.username) {
_361      rowDiv.addClass('own-message');
_361    }
_361
_361    tc.$messageList.append(rowDiv);
_361    scrollToMessageListBottom();
_361  };
_361
_361  function notifyMemberJoined(member) {
_361    notify(member.identity + ' joined the channel')
_361  }
_361
_361  function notifyMemberLeft(member) {
_361    notify(member.identity + ' left the channel');
_361  }
_361
_361  function notify(message) {
_361    var row = $('<div>').addClass('col-md-12');
_361    row.loadTemplate('#member-notification-template', {
_361      status: message
_361    });
_361    tc.$messageList.append(row);
_361    scrollToMessageListBottom();
_361  }
_361
_361  function showTypingStarted(member) {
_361    $typingPlaceholder.text(member.identity + ' is typing...');
_361  }
_361
_361  function hideTypingStarted(member) {
_361    $typingPlaceholder.text('');
_361  }
_361
_361  function scrollToMessageListBottom() {
_361    tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_361  }
_361
_361  function updateChannelUI(selectedChannel) {
_361    var channelElements = $('.channel-element').toArray();
_361    var channelElement = channelElements.filter(function(element) {
_361      return $(element).data().sid === selectedChannel.sid;
_361    });
_361    channelElement = $(channelElement);
_361    if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.currentChannelContainer = channelElement;
_361    }
_361    tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_361    channelElement.removeClass('unselected-channel').addClass('selected-channel');
_361    tc.currentChannelContainer = channelElement;
_361  }
_361
_361  function showAddChannelInput() {
_361    if (tc.messagingClient) {
_361      $newChannelInputRow.addClass('showing').removeClass('not-showing');
_361      $channelList.addClass('showing').removeClass('not-showing');
_361      $newChannelInput.focus();
_361    }
_361  }
_361
_361  function hideAddChannelInput() {
_361    $newChannelInputRow.addClass('not-showing').removeClass('showing');
_361    $channelList.addClass('not-showing').removeClass('showing');
_361    $newChannelInput.val('');
_361  }
_361
_361  function addChannel(channel) {
_361    if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.generalChannel = channel;
_361    }
_361    var rowDiv = $('<div>').addClass('row channel-row');
_361    rowDiv.loadTemplate('#channel-template', {
_361      channelName: channel.friendlyName
_361    });
_361
_361    var channelP = rowDiv.children().children().first();
_361
_361    rowDiv.on('click', selectChannel);
_361    channelP.data('sid', channel.sid);
_361    if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_361      tc.currentChannelContainer = channelP;
_361      channelP.addClass('selected-channel');
_361    }
_361    else {
_361      channelP.addClass('unselected-channel')
_361    }
_361
_361    $channelList.append(rowDiv);
_361  }
_361
_361  function deleteCurrentChannel() {
_361    if (!tc.currentChannel) {
_361      return;
_361    }
_361    if (tc.currentChannel.sid === tc.generalChannel.sid) {
_361      alert('You cannot delete the general channel');
_361      return;
_361    }
_361    tc.currentChannel.delete().then(function(channel) {
_361      console.log('channel: '+ channel.friendlyName + ' deleted');
_361      setupChannel(tc.generalChannel);
_361    });
_361  }
_361
_361  function selectChannel(event) {
_361    var target = $(event.target);
_361    var channelSid = target.data().sid;
_361    var selectedChannel = tc.channelArray.filter(function(channel) {
_361      return channel.sid === channelSid;
_361    })[0];
_361    if (selectedChannel === tc.currentChannel) {
_361      return;
_361    }
_361    setupChannel(selectedChannel);
_361  };
_361
_361  function disconnectClient() {
_361    leaveCurrentChannel();
_361    $channelList.text('');
_361    tc.$messageList.text('');
_361    channels = undefined;
_361    $statusRow.addClass('disconnected').removeClass('connected');
_361    tc.$messageList.addClass('disconnected').removeClass('connected');
_361    $connectPanel.addClass('disconnected').removeClass('connected');
_361    $inputText.removeClass('with-shadow');
_361    $typingRow.addClass('disconnected').removeClass('connected');
_361  }
_361
_361  tc.sortChannelsByName = function(channels) {
_361    return channels.sort(function(a, b) {
_361      if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return -1;
_361      }
_361      if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return 1;
_361      }
_361      return a.friendlyName.localeCompare(b.friendlyName);
_361    });
_361  };
_361
_361  return tc;
_361})();

We've actually got a real chat app going here, but let's make it more interesting with multiple channels.

Create a Channel

When a user clicks on the "+ Channel" link we'll show an input text field where it's possible to type the name of the new channel. Creating a channel is as simple as calling createChannel with an object that has the friendlyName key. You can create a channel with more options listed on the Channels section of the Programmable Chat documentation.

Create a Channel

public/js/twiliochat.js


_361var twiliochat = (function() {
_361  var tc = {};
_361
_361  var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_361  var GENERAL_CHANNEL_NAME = 'General Channel';
_361  var MESSAGES_HISTORY_LIMIT = 50;
_361
_361  var $channelList;
_361  var $inputText;
_361  var $usernameInput;
_361  var $statusRow;
_361  var $connectPanel;
_361  var $newChannelInputRow;
_361  var $newChannelInput;
_361  var $typingRow;
_361  var $typingPlaceholder;
_361
_361  $(document).ready(function() {
_361    tc.$messageList = $('#message-list');
_361    $channelList = $('#channel-list');
_361    $inputText = $('#input-text');
_361    $usernameInput = $('#username-input');
_361    $statusRow = $('#status-row');
_361    $connectPanel = $('#connect-panel');
_361    $newChannelInputRow = $('#new-channel-input-row');
_361    $newChannelInput = $('#new-channel-input');
_361    $typingRow = $('#typing-row');
_361    $typingPlaceholder = $('#typing-placeholder');
_361    $usernameInput.focus();
_361    $usernameInput.on('keypress', handleUsernameInputKeypress);
_361    $inputText.on('keypress', handleInputTextKeypress);
_361    $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_361    $('#connect-image').on('click', connectClientWithUsername);
_361    $('#add-channel-image').on('click', showAddChannelInput);
_361    $('#leave-span').on('click', disconnectClient);
_361    $('#delete-channel-span').on('click', deleteCurrentChannel);
_361  });
_361
_361  function handleUsernameInputKeypress(event) {
_361    if (event.keyCode === 13){
_361      connectClientWithUsername();
_361    }
_361  }
_361
_361  function handleInputTextKeypress(event) {
_361    if (event.keyCode === 13) {
_361      tc.currentChannel.sendMessage($(this).val());
_361      event.preventDefault();
_361      $(this).val('');
_361    }
_361    else {
_361      notifyTyping();
_361    }
_361  }
_361
_361  var notifyTyping = $.throttle(function() {
_361    tc.currentChannel.typing();
_361  }, 1000);
_361
_361  tc.handleNewChannelInputKeypress = function(event) {
_361    if (event.keyCode === 13) {
_361      tc.messagingClient.createChannel({
_361        friendlyName: $newChannelInput.val()
_361      }).then(hideAddChannelInput);
_361      $(this).val('');
_361      event.preventDefault();
_361    }
_361  };
_361
_361  function connectClientWithUsername() {
_361    var usernameText = $usernameInput.val();
_361    $usernameInput.val('');
_361    if (usernameText == '') {
_361      alert('Username cannot be empty');
_361      return;
_361    }
_361    tc.username = usernameText;
_361    fetchAccessToken(tc.username, connectMessagingClient);
_361  }
_361
_361  function fetchAccessToken(username, handler) {
_361    $.post('/token', {identity: username}, null, 'json')
_361      .done(function(response) {
_361        handler(response.token);
_361      })
_361      .fail(function(error) {
_361        console.log('Failed to fetch the Access Token with error: ' + error);
_361      });
_361  }
_361
_361  function connectMessagingClient(token) {
_361    // Initialize the Chat messaging client
_361    tc.accessManager = new Twilio.AccessManager(token);
_361    Twilio.Chat.Client.create(token).then(function(client) {
_361      tc.messagingClient = client;
_361      updateConnectedUI();
_361      tc.loadChannelList(tc.joinGeneralChannel);
_361      tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('tokenExpired', refreshToken);
_361    });
_361  }
_361
_361  function refreshToken() {
_361    fetchAccessToken(tc.username, setNewToken);
_361  }
_361
_361  function setNewToken(tokenResponse) {
_361    tc.accessManager.updateToken(tokenResponse.token);
_361  }
_361
_361  function updateConnectedUI() {
_361    $('#username-span').text(tc.username);
_361    $statusRow.addClass('connected').removeClass('disconnected');
_361    tc.$messageList.addClass('connected').removeClass('disconnected');
_361    $connectPanel.addClass('connected').removeClass('disconnected');
_361    $inputText.addClass('with-shadow');
_361    $typingRow.addClass('connected').removeClass('disconnected');
_361  }
_361
_361  tc.loadChannelList = function(handler) {
_361    if (tc.messagingClient === undefined) {
_361      console.log('Client is not initialized');
_361      return;
_361    }
_361
_361    tc.messagingClient.getPublicChannelDescriptors().then(function(channels) {
_361      tc.channelArray = tc.sortChannelsByName(channels.items);
_361      $channelList.text('');
_361      tc.channelArray.forEach(addChannel);
_361      if (typeof handler === 'function') {
_361        handler();
_361      }
_361    });
_361  };
_361
_361  tc.joinGeneralChannel = function() {
_361    console.log('Attempting to join "general" chat channel...');
_361    if (!tc.generalChannel) {
_361      // If it doesn't exist, let's create it
_361      tc.messagingClient.createChannel({
_361        uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_361        friendlyName: GENERAL_CHANNEL_NAME
_361      }).then(function(channel) {
_361        console.log('Created general channel');
_361        tc.generalChannel = channel;
_361        tc.loadChannelList(tc.joinGeneralChannel);
_361      });
_361    }
_361    else {
_361      console.log('Found general channel:');
_361      setupChannel(tc.generalChannel);
_361    }
_361  };
_361
_361  function initChannel(channel) {
_361    console.log('Initialized channel ' + channel.friendlyName);
_361    return tc.messagingClient.getChannelBySid(channel.sid);
_361  }
_361
_361  function joinChannel(_channel) {
_361    return _channel.join()
_361      .then(function(joinedChannel) {
_361        console.log('Joined channel ' + joinedChannel.friendlyName);
_361        updateChannelUI(_channel);
_361        tc.currentChannel = _channel;
_361        tc.loadMessages();
_361        return joinedChannel;
_361      });
_361  }
_361
_361  function initChannelEvents() {
_361    console.log(tc.currentChannel.friendlyName + ' ready.');
_361    tc.currentChannel.on('messageAdded', tc.addMessageToList);
_361    tc.currentChannel.on('typingStarted', showTypingStarted);
_361    tc.currentChannel.on('typingEnded', hideTypingStarted);
_361    tc.currentChannel.on('memberJoined', notifyMemberJoined);
_361    tc.currentChannel.on('memberLeft', notifyMemberLeft);
_361    $inputText.prop('disabled', false).focus();
_361  }
_361
_361  function setupChannel(channel) {
_361    return leaveCurrentChannel()
_361      .then(function() {
_361        return initChannel(channel);
_361      })
_361      .then(function(_channel) {
_361        return joinChannel(_channel);
_361      })
_361      .then(initChannelEvents);
_361  }
_361
_361  tc.loadMessages = function() {
_361    tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_361      messages.items.forEach(tc.addMessageToList);
_361    });
_361  };
_361
_361  function leaveCurrentChannel() {
_361    if (tc.currentChannel) {
_361      return tc.currentChannel.leave().then(function(leftChannel) {
_361        console.log('left ' + leftChannel.friendlyName);
_361        leftChannel.removeListener('messageAdded', tc.addMessageToList);
_361        leftChannel.removeListener('typingStarted', showTypingStarted);
_361        leftChannel.removeListener('typingEnded', hideTypingStarted);
_361        leftChannel.removeListener('memberJoined', notifyMemberJoined);
_361        leftChannel.removeListener('memberLeft', notifyMemberLeft);
_361      });
_361    } else {
_361      return Promise.resolve();
_361    }
_361  }
_361
_361  tc.addMessageToList = function(message) {
_361    var rowDiv = $('<div>').addClass('row no-margin');
_361    rowDiv.loadTemplate($('#message-template'), {
_361      username: message.author,
_361      date: dateFormatter.getTodayDate(message.dateCreated),
_361      body: message.body
_361    });
_361    if (message.author === tc.username) {
_361      rowDiv.addClass('own-message');
_361    }
_361
_361    tc.$messageList.append(rowDiv);
_361    scrollToMessageListBottom();
_361  };
_361
_361  function notifyMemberJoined(member) {
_361    notify(member.identity + ' joined the channel')
_361  }
_361
_361  function notifyMemberLeft(member) {
_361    notify(member.identity + ' left the channel');
_361  }
_361
_361  function notify(message) {
_361    var row = $('<div>').addClass('col-md-12');
_361    row.loadTemplate('#member-notification-template', {
_361      status: message
_361    });
_361    tc.$messageList.append(row);
_361    scrollToMessageListBottom();
_361  }
_361
_361  function showTypingStarted(member) {
_361    $typingPlaceholder.text(member.identity + ' is typing...');
_361  }
_361
_361  function hideTypingStarted(member) {
_361    $typingPlaceholder.text('');
_361  }
_361
_361  function scrollToMessageListBottom() {
_361    tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_361  }
_361
_361  function updateChannelUI(selectedChannel) {
_361    var channelElements = $('.channel-element').toArray();
_361    var channelElement = channelElements.filter(function(element) {
_361      return $(element).data().sid === selectedChannel.sid;
_361    });
_361    channelElement = $(channelElement);
_361    if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.currentChannelContainer = channelElement;
_361    }
_361    tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_361    channelElement.removeClass('unselected-channel').addClass('selected-channel');
_361    tc.currentChannelContainer = channelElement;
_361  }
_361
_361  function showAddChannelInput() {
_361    if (tc.messagingClient) {
_361      $newChannelInputRow.addClass('showing').removeClass('not-showing');
_361      $channelList.addClass('showing').removeClass('not-showing');
_361      $newChannelInput.focus();
_361    }
_361  }
_361
_361  function hideAddChannelInput() {
_361    $newChannelInputRow.addClass('not-showing').removeClass('showing');
_361    $channelList.addClass('not-showing').removeClass('showing');
_361    $newChannelInput.val('');
_361  }
_361
_361  function addChannel(channel) {
_361    if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.generalChannel = channel;
_361    }
_361    var rowDiv = $('<div>').addClass('row channel-row');
_361    rowDiv.loadTemplate('#channel-template', {
_361      channelName: channel.friendlyName
_361    });
_361
_361    var channelP = rowDiv.children().children().first();
_361
_361    rowDiv.on('click', selectChannel);
_361    channelP.data('sid', channel.sid);
_361    if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_361      tc.currentChannelContainer = channelP;
_361      channelP.addClass('selected-channel');
_361    }
_361    else {
_361      channelP.addClass('unselected-channel')
_361    }
_361
_361    $channelList.append(rowDiv);
_361  }
_361
_361  function deleteCurrentChannel() {
_361    if (!tc.currentChannel) {
_361      return;
_361    }
_361    if (tc.currentChannel.sid === tc.generalChannel.sid) {
_361      alert('You cannot delete the general channel');
_361      return;
_361    }
_361    tc.currentChannel.delete().then(function(channel) {
_361      console.log('channel: '+ channel.friendlyName + ' deleted');
_361      setupChannel(tc.generalChannel);
_361    });
_361  }
_361
_361  function selectChannel(event) {
_361    var target = $(event.target);
_361    var channelSid = target.data().sid;
_361    var selectedChannel = tc.channelArray.filter(function(channel) {
_361      return channel.sid === channelSid;
_361    })[0];
_361    if (selectedChannel === tc.currentChannel) {
_361      return;
_361    }
_361    setupChannel(selectedChannel);
_361  };
_361
_361  function disconnectClient() {
_361    leaveCurrentChannel();
_361    $channelList.text('');
_361    tc.$messageList.text('');
_361    channels = undefined;
_361    $statusRow.addClass('disconnected').removeClass('connected');
_361    tc.$messageList.addClass('disconnected').removeClass('connected');
_361    $connectPanel.addClass('disconnected').removeClass('connected');
_361    $inputText.removeClass('with-shadow');
_361    $typingRow.addClass('disconnected').removeClass('connected');
_361  }
_361
_361  tc.sortChannelsByName = function(channels) {
_361    return channels.sort(function(a, b) {
_361      if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return -1;
_361      }
_361      if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return 1;
_361      }
_361      return a.friendlyName.localeCompare(b.friendlyName);
_361    });
_361  };
_361
_361  return tc;
_361})();

Next, we will see how we can switch between channels.

Join Other Channels

When you tap on the name of a channel from the sidebar, that channel is set as the selectedChannel. The selectChannel method takes care of joining to the selected channel and setting up the selectedChannel.

Join Other Channels

public/js/twiliochat.js


_361var twiliochat = (function() {
_361  var tc = {};
_361
_361  var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_361  var GENERAL_CHANNEL_NAME = 'General Channel';
_361  var MESSAGES_HISTORY_LIMIT = 50;
_361
_361  var $channelList;
_361  var $inputText;
_361  var $usernameInput;
_361  var $statusRow;
_361  var $connectPanel;
_361  var $newChannelInputRow;
_361  var $newChannelInput;
_361  var $typingRow;
_361  var $typingPlaceholder;
_361
_361  $(document).ready(function() {
_361    tc.$messageList = $('#message-list');
_361    $channelList = $('#channel-list');
_361    $inputText = $('#input-text');
_361    $usernameInput = $('#username-input');
_361    $statusRow = $('#status-row');
_361    $connectPanel = $('#connect-panel');
_361    $newChannelInputRow = $('#new-channel-input-row');
_361    $newChannelInput = $('#new-channel-input');
_361    $typingRow = $('#typing-row');
_361    $typingPlaceholder = $('#typing-placeholder');
_361    $usernameInput.focus();
_361    $usernameInput.on('keypress', handleUsernameInputKeypress);
_361    $inputText.on('keypress', handleInputTextKeypress);
_361    $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_361    $('#connect-image').on('click', connectClientWithUsername);
_361    $('#add-channel-image').on('click', showAddChannelInput);
_361    $('#leave-span').on('click', disconnectClient);
_361    $('#delete-channel-span').on('click', deleteCurrentChannel);
_361  });
_361
_361  function handleUsernameInputKeypress(event) {
_361    if (event.keyCode === 13){
_361      connectClientWithUsername();
_361    }
_361  }
_361
_361  function handleInputTextKeypress(event) {
_361    if (event.keyCode === 13) {
_361      tc.currentChannel.sendMessage($(this).val());
_361      event.preventDefault();
_361      $(this).val('');
_361    }
_361    else {
_361      notifyTyping();
_361    }
_361  }
_361
_361  var notifyTyping = $.throttle(function() {
_361    tc.currentChannel.typing();
_361  }, 1000);
_361
_361  tc.handleNewChannelInputKeypress = function(event) {
_361    if (event.keyCode === 13) {
_361      tc.messagingClient.createChannel({
_361        friendlyName: $newChannelInput.val()
_361      }).then(hideAddChannelInput);
_361      $(this).val('');
_361      event.preventDefault();
_361    }
_361  };
_361
_361  function connectClientWithUsername() {
_361    var usernameText = $usernameInput.val();
_361    $usernameInput.val('');
_361    if (usernameText == '') {
_361      alert('Username cannot be empty');
_361      return;
_361    }
_361    tc.username = usernameText;
_361    fetchAccessToken(tc.username, connectMessagingClient);
_361  }
_361
_361  function fetchAccessToken(username, handler) {
_361    $.post('/token', {identity: username}, null, 'json')
_361      .done(function(response) {
_361        handler(response.token);
_361      })
_361      .fail(function(error) {
_361        console.log('Failed to fetch the Access Token with error: ' + error);
_361      });
_361  }
_361
_361  function connectMessagingClient(token) {
_361    // Initialize the Chat messaging client
_361    tc.accessManager = new Twilio.AccessManager(token);
_361    Twilio.Chat.Client.create(token).then(function(client) {
_361      tc.messagingClient = client;
_361      updateConnectedUI();
_361      tc.loadChannelList(tc.joinGeneralChannel);
_361      tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('tokenExpired', refreshToken);
_361    });
_361  }
_361
_361  function refreshToken() {
_361    fetchAccessToken(tc.username, setNewToken);
_361  }
_361
_361  function setNewToken(tokenResponse) {
_361    tc.accessManager.updateToken(tokenResponse.token);
_361  }
_361
_361  function updateConnectedUI() {
_361    $('#username-span').text(tc.username);
_361    $statusRow.addClass('connected').removeClass('disconnected');
_361    tc.$messageList.addClass('connected').removeClass('disconnected');
_361    $connectPanel.addClass('connected').removeClass('disconnected');
_361    $inputText.addClass('with-shadow');
_361    $typingRow.addClass('connected').removeClass('disconnected');
_361  }
_361
_361  tc.loadChannelList = function(handler) {
_361    if (tc.messagingClient === undefined) {
_361      console.log('Client is not initialized');
_361      return;
_361    }
_361
_361    tc.messagingClient.getPublicChannelDescriptors().then(function(channels) {
_361      tc.channelArray = tc.sortChannelsByName(channels.items);
_361      $channelList.text('');
_361      tc.channelArray.forEach(addChannel);
_361      if (typeof handler === 'function') {
_361        handler();
_361      }
_361    });
_361  };
_361
_361  tc.joinGeneralChannel = function() {
_361    console.log('Attempting to join "general" chat channel...');
_361    if (!tc.generalChannel) {
_361      // If it doesn't exist, let's create it
_361      tc.messagingClient.createChannel({
_361        uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_361        friendlyName: GENERAL_CHANNEL_NAME
_361      }).then(function(channel) {
_361        console.log('Created general channel');
_361        tc.generalChannel = channel;
_361        tc.loadChannelList(tc.joinGeneralChannel);
_361      });
_361    }
_361    else {
_361      console.log('Found general channel:');
_361      setupChannel(tc.generalChannel);
_361    }
_361  };
_361
_361  function initChannel(channel) {
_361    console.log('Initialized channel ' + channel.friendlyName);
_361    return tc.messagingClient.getChannelBySid(channel.sid);
_361  }
_361
_361  function joinChannel(_channel) {
_361    return _channel.join()
_361      .then(function(joinedChannel) {
_361        console.log('Joined channel ' + joinedChannel.friendlyName);
_361        updateChannelUI(_channel);
_361        tc.currentChannel = _channel;
_361        tc.loadMessages();
_361        return joinedChannel;
_361      });
_361  }
_361
_361  function initChannelEvents() {
_361    console.log(tc.currentChannel.friendlyName + ' ready.');
_361    tc.currentChannel.on('messageAdded', tc.addMessageToList);
_361    tc.currentChannel.on('typingStarted', showTypingStarted);
_361    tc.currentChannel.on('typingEnded', hideTypingStarted);
_361    tc.currentChannel.on('memberJoined', notifyMemberJoined);
_361    tc.currentChannel.on('memberLeft', notifyMemberLeft);
_361    $inputText.prop('disabled', false).focus();
_361  }
_361
_361  function setupChannel(channel) {
_361    return leaveCurrentChannel()
_361      .then(function() {
_361        return initChannel(channel);
_361      })
_361      .then(function(_channel) {
_361        return joinChannel(_channel);
_361      })
_361      .then(initChannelEvents);
_361  }
_361
_361  tc.loadMessages = function() {
_361    tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_361      messages.items.forEach(tc.addMessageToList);
_361    });
_361  };
_361
_361  function leaveCurrentChannel() {
_361    if (tc.currentChannel) {
_361      return tc.currentChannel.leave().then(function(leftChannel) {
_361        console.log('left ' + leftChannel.friendlyName);
_361        leftChannel.removeListener('messageAdded', tc.addMessageToList);
_361        leftChannel.removeListener('typingStarted', showTypingStarted);
_361        leftChannel.removeListener('typingEnded', hideTypingStarted);
_361        leftChannel.removeListener('memberJoined', notifyMemberJoined);
_361        leftChannel.removeListener('memberLeft', notifyMemberLeft);
_361      });
_361    } else {
_361      return Promise.resolve();
_361    }
_361  }
_361
_361  tc.addMessageToList = function(message) {
_361    var rowDiv = $('<div>').addClass('row no-margin');
_361    rowDiv.loadTemplate($('#message-template'), {
_361      username: message.author,
_361      date: dateFormatter.getTodayDate(message.dateCreated),
_361      body: message.body
_361    });
_361    if (message.author === tc.username) {
_361      rowDiv.addClass('own-message');
_361    }
_361
_361    tc.$messageList.append(rowDiv);
_361    scrollToMessageListBottom();
_361  };
_361
_361  function notifyMemberJoined(member) {
_361    notify(member.identity + ' joined the channel')
_361  }
_361
_361  function notifyMemberLeft(member) {
_361    notify(member.identity + ' left the channel');
_361  }
_361
_361  function notify(message) {
_361    var row = $('<div>').addClass('col-md-12');
_361    row.loadTemplate('#member-notification-template', {
_361      status: message
_361    });
_361    tc.$messageList.append(row);
_361    scrollToMessageListBottom();
_361  }
_361
_361  function showTypingStarted(member) {
_361    $typingPlaceholder.text(member.identity + ' is typing...');
_361  }
_361
_361  function hideTypingStarted(member) {
_361    $typingPlaceholder.text('');
_361  }
_361
_361  function scrollToMessageListBottom() {
_361    tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_361  }
_361
_361  function updateChannelUI(selectedChannel) {
_361    var channelElements = $('.channel-element').toArray();
_361    var channelElement = channelElements.filter(function(element) {
_361      return $(element).data().sid === selectedChannel.sid;
_361    });
_361    channelElement = $(channelElement);
_361    if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.currentChannelContainer = channelElement;
_361    }
_361    tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_361    channelElement.removeClass('unselected-channel').addClass('selected-channel');
_361    tc.currentChannelContainer = channelElement;
_361  }
_361
_361  function showAddChannelInput() {
_361    if (tc.messagingClient) {
_361      $newChannelInputRow.addClass('showing').removeClass('not-showing');
_361      $channelList.addClass('showing').removeClass('not-showing');
_361      $newChannelInput.focus();
_361    }
_361  }
_361
_361  function hideAddChannelInput() {
_361    $newChannelInputRow.addClass('not-showing').removeClass('showing');
_361    $channelList.addClass('not-showing').removeClass('showing');
_361    $newChannelInput.val('');
_361  }
_361
_361  function addChannel(channel) {
_361    if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.generalChannel = channel;
_361    }
_361    var rowDiv = $('<div>').addClass('row channel-row');
_361    rowDiv.loadTemplate('#channel-template', {
_361      channelName: channel.friendlyName
_361    });
_361
_361    var channelP = rowDiv.children().children().first();
_361
_361    rowDiv.on('click', selectChannel);
_361    channelP.data('sid', channel.sid);
_361    if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_361      tc.currentChannelContainer = channelP;
_361      channelP.addClass('selected-channel');
_361    }
_361    else {
_361      channelP.addClass('unselected-channel')
_361    }
_361
_361    $channelList.append(rowDiv);
_361  }
_361
_361  function deleteCurrentChannel() {
_361    if (!tc.currentChannel) {
_361      return;
_361    }
_361    if (tc.currentChannel.sid === tc.generalChannel.sid) {
_361      alert('You cannot delete the general channel');
_361      return;
_361    }
_361    tc.currentChannel.delete().then(function(channel) {
_361      console.log('channel: '+ channel.friendlyName + ' deleted');
_361      setupChannel(tc.generalChannel);
_361    });
_361  }
_361
_361  function selectChannel(event) {
_361    var target = $(event.target);
_361    var channelSid = target.data().sid;
_361    var selectedChannel = tc.channelArray.filter(function(channel) {
_361      return channel.sid === channelSid;
_361    })[0];
_361    if (selectedChannel === tc.currentChannel) {
_361      return;
_361    }
_361    setupChannel(selectedChannel);
_361  };
_361
_361  function disconnectClient() {
_361    leaveCurrentChannel();
_361    $channelList.text('');
_361    tc.$messageList.text('');
_361    channels = undefined;
_361    $statusRow.addClass('disconnected').removeClass('connected');
_361    tc.$messageList.addClass('disconnected').removeClass('connected');
_361    $connectPanel.addClass('disconnected').removeClass('connected');
_361    $inputText.removeClass('with-shadow');
_361    $typingRow.addClass('disconnected').removeClass('connected');
_361  }
_361
_361  tc.sortChannelsByName = function(channels) {
_361    return channels.sort(function(a, b) {
_361      if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return -1;
_361      }
_361      if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return 1;
_361      }
_361      return a.friendlyName.localeCompare(b.friendlyName);
_361    });
_361  };
_361
_361  return tc;
_361})();

At some point, your users will want to delete a channel. Let's have a look at how that can be done.

Delete a Channel

Deleting a channel is easier than creating one. The application lets the user delete the channel they are currently on through the "delete current channel" link. The only thing you need to do to actually delete the channel from Twilio, is call the delete method on the channel you are trying to delete. Like other methods on the Channel object, it'll return a promise where you can set the success handler.

Delete a Channel

public/js/twiliochat.js


_361var twiliochat = (function() {
_361  var tc = {};
_361
_361  var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_361  var GENERAL_CHANNEL_NAME = 'General Channel';
_361  var MESSAGES_HISTORY_LIMIT = 50;
_361
_361  var $channelList;
_361  var $inputText;
_361  var $usernameInput;
_361  var $statusRow;
_361  var $connectPanel;
_361  var $newChannelInputRow;
_361  var $newChannelInput;
_361  var $typingRow;
_361  var $typingPlaceholder;
_361
_361  $(document).ready(function() {
_361    tc.$messageList = $('#message-list');
_361    $channelList = $('#channel-list');
_361    $inputText = $('#input-text');
_361    $usernameInput = $('#username-input');
_361    $statusRow = $('#status-row');
_361    $connectPanel = $('#connect-panel');
_361    $newChannelInputRow = $('#new-channel-input-row');
_361    $newChannelInput = $('#new-channel-input');
_361    $typingRow = $('#typing-row');
_361    $typingPlaceholder = $('#typing-placeholder');
_361    $usernameInput.focus();
_361    $usernameInput.on('keypress', handleUsernameInputKeypress);
_361    $inputText.on('keypress', handleInputTextKeypress);
_361    $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_361    $('#connect-image').on('click', connectClientWithUsername);
_361    $('#add-channel-image').on('click', showAddChannelInput);
_361    $('#leave-span').on('click', disconnectClient);
_361    $('#delete-channel-span').on('click', deleteCurrentChannel);
_361  });
_361
_361  function handleUsernameInputKeypress(event) {
_361    if (event.keyCode === 13){
_361      connectClientWithUsername();
_361    }
_361  }
_361
_361  function handleInputTextKeypress(event) {
_361    if (event.keyCode === 13) {
_361      tc.currentChannel.sendMessage($(this).val());
_361      event.preventDefault();
_361      $(this).val('');
_361    }
_361    else {
_361      notifyTyping();
_361    }
_361  }
_361
_361  var notifyTyping = $.throttle(function() {
_361    tc.currentChannel.typing();
_361  }, 1000);
_361
_361  tc.handleNewChannelInputKeypress = function(event) {
_361    if (event.keyCode === 13) {
_361      tc.messagingClient.createChannel({
_361        friendlyName: $newChannelInput.val()
_361      }).then(hideAddChannelInput);
_361      $(this).val('');
_361      event.preventDefault();
_361    }
_361  };
_361
_361  function connectClientWithUsername() {
_361    var usernameText = $usernameInput.val();
_361    $usernameInput.val('');
_361    if (usernameText == '') {
_361      alert('Username cannot be empty');
_361      return;
_361    }
_361    tc.username = usernameText;
_361    fetchAccessToken(tc.username, connectMessagingClient);
_361  }
_361
_361  function fetchAccessToken(username, handler) {
_361    $.post('/token', {identity: username}, null, 'json')
_361      .done(function(response) {
_361        handler(response.token);
_361      })
_361      .fail(function(error) {
_361        console.log('Failed to fetch the Access Token with error: ' + error);
_361      });
_361  }
_361
_361  function connectMessagingClient(token) {
_361    // Initialize the Chat messaging client
_361    tc.accessManager = new Twilio.AccessManager(token);
_361    Twilio.Chat.Client.create(token).then(function(client) {
_361      tc.messagingClient = client;
_361      updateConnectedUI();
_361      tc.loadChannelList(tc.joinGeneralChannel);
_361      tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_361      tc.messagingClient.on('tokenExpired', refreshToken);
_361    });
_361  }
_361
_361  function refreshToken() {
_361    fetchAccessToken(tc.username, setNewToken);
_361  }
_361
_361  function setNewToken(tokenResponse) {
_361    tc.accessManager.updateToken(tokenResponse.token);
_361  }
_361
_361  function updateConnectedUI() {
_361    $('#username-span').text(tc.username);
_361    $statusRow.addClass('connected').removeClass('disconnected');
_361    tc.$messageList.addClass('connected').removeClass('disconnected');
_361    $connectPanel.addClass('connected').removeClass('disconnected');
_361    $inputText.addClass('with-shadow');
_361    $typingRow.addClass('connected').removeClass('disconnected');
_361  }
_361
_361  tc.loadChannelList = function(handler) {
_361    if (tc.messagingClient === undefined) {
_361      console.log('Client is not initialized');
_361      return;
_361    }
_361
_361    tc.messagingClient.getPublicChannelDescriptors().then(function(channels) {
_361      tc.channelArray = tc.sortChannelsByName(channels.items);
_361      $channelList.text('');
_361      tc.channelArray.forEach(addChannel);
_361      if (typeof handler === 'function') {
_361        handler();
_361      }
_361    });
_361  };
_361
_361  tc.joinGeneralChannel = function() {
_361    console.log('Attempting to join "general" chat channel...');
_361    if (!tc.generalChannel) {
_361      // If it doesn't exist, let's create it
_361      tc.messagingClient.createChannel({
_361        uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_361        friendlyName: GENERAL_CHANNEL_NAME
_361      }).then(function(channel) {
_361        console.log('Created general channel');
_361        tc.generalChannel = channel;
_361        tc.loadChannelList(tc.joinGeneralChannel);
_361      });
_361    }
_361    else {
_361      console.log('Found general channel:');
_361      setupChannel(tc.generalChannel);
_361    }
_361  };
_361
_361  function initChannel(channel) {
_361    console.log('Initialized channel ' + channel.friendlyName);
_361    return tc.messagingClient.getChannelBySid(channel.sid);
_361  }
_361
_361  function joinChannel(_channel) {
_361    return _channel.join()
_361      .then(function(joinedChannel) {
_361        console.log('Joined channel ' + joinedChannel.friendlyName);
_361        updateChannelUI(_channel);
_361        tc.currentChannel = _channel;
_361        tc.loadMessages();
_361        return joinedChannel;
_361      });
_361  }
_361
_361  function initChannelEvents() {
_361    console.log(tc.currentChannel.friendlyName + ' ready.');
_361    tc.currentChannel.on('messageAdded', tc.addMessageToList);
_361    tc.currentChannel.on('typingStarted', showTypingStarted);
_361    tc.currentChannel.on('typingEnded', hideTypingStarted);
_361    tc.currentChannel.on('memberJoined', notifyMemberJoined);
_361    tc.currentChannel.on('memberLeft', notifyMemberLeft);
_361    $inputText.prop('disabled', false).focus();
_361  }
_361
_361  function setupChannel(channel) {
_361    return leaveCurrentChannel()
_361      .then(function() {
_361        return initChannel(channel);
_361      })
_361      .then(function(_channel) {
_361        return joinChannel(_channel);
_361      })
_361      .then(initChannelEvents);
_361  }
_361
_361  tc.loadMessages = function() {
_361    tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_361      messages.items.forEach(tc.addMessageToList);
_361    });
_361  };
_361
_361  function leaveCurrentChannel() {
_361    if (tc.currentChannel) {
_361      return tc.currentChannel.leave().then(function(leftChannel) {
_361        console.log('left ' + leftChannel.friendlyName);
_361        leftChannel.removeListener('messageAdded', tc.addMessageToList);
_361        leftChannel.removeListener('typingStarted', showTypingStarted);
_361        leftChannel.removeListener('typingEnded', hideTypingStarted);
_361        leftChannel.removeListener('memberJoined', notifyMemberJoined);
_361        leftChannel.removeListener('memberLeft', notifyMemberLeft);
_361      });
_361    } else {
_361      return Promise.resolve();
_361    }
_361  }
_361
_361  tc.addMessageToList = function(message) {
_361    var rowDiv = $('<div>').addClass('row no-margin');
_361    rowDiv.loadTemplate($('#message-template'), {
_361      username: message.author,
_361      date: dateFormatter.getTodayDate(message.dateCreated),
_361      body: message.body
_361    });
_361    if (message.author === tc.username) {
_361      rowDiv.addClass('own-message');
_361    }
_361
_361    tc.$messageList.append(rowDiv);
_361    scrollToMessageListBottom();
_361  };
_361
_361  function notifyMemberJoined(member) {
_361    notify(member.identity + ' joined the channel')
_361  }
_361
_361  function notifyMemberLeft(member) {
_361    notify(member.identity + ' left the channel');
_361  }
_361
_361  function notify(message) {
_361    var row = $('<div>').addClass('col-md-12');
_361    row.loadTemplate('#member-notification-template', {
_361      status: message
_361    });
_361    tc.$messageList.append(row);
_361    scrollToMessageListBottom();
_361  }
_361
_361  function showTypingStarted(member) {
_361    $typingPlaceholder.text(member.identity + ' is typing...');
_361  }
_361
_361  function hideTypingStarted(member) {
_361    $typingPlaceholder.text('');
_361  }
_361
_361  function scrollToMessageListBottom() {
_361    tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_361  }
_361
_361  function updateChannelUI(selectedChannel) {
_361    var channelElements = $('.channel-element').toArray();
_361    var channelElement = channelElements.filter(function(element) {
_361      return $(element).data().sid === selectedChannel.sid;
_361    });
_361    channelElement = $(channelElement);
_361    if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.currentChannelContainer = channelElement;
_361    }
_361    tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_361    channelElement.removeClass('unselected-channel').addClass('selected-channel');
_361    tc.currentChannelContainer = channelElement;
_361  }
_361
_361  function showAddChannelInput() {
_361    if (tc.messagingClient) {
_361      $newChannelInputRow.addClass('showing').removeClass('not-showing');
_361      $channelList.addClass('showing').removeClass('not-showing');
_361      $newChannelInput.focus();
_361    }
_361  }
_361
_361  function hideAddChannelInput() {
_361    $newChannelInputRow.addClass('not-showing').removeClass('showing');
_361    $channelList.addClass('not-showing').removeClass('showing');
_361    $newChannelInput.val('');
_361  }
_361
_361  function addChannel(channel) {
_361    if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_361      tc.generalChannel = channel;
_361    }
_361    var rowDiv = $('<div>').addClass('row channel-row');
_361    rowDiv.loadTemplate('#channel-template', {
_361      channelName: channel.friendlyName
_361    });
_361
_361    var channelP = rowDiv.children().children().first();
_361
_361    rowDiv.on('click', selectChannel);
_361    channelP.data('sid', channel.sid);
_361    if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_361      tc.currentChannelContainer = channelP;
_361      channelP.addClass('selected-channel');
_361    }
_361    else {
_361      channelP.addClass('unselected-channel')
_361    }
_361
_361    $channelList.append(rowDiv);
_361  }
_361
_361  function deleteCurrentChannel() {
_361    if (!tc.currentChannel) {
_361      return;
_361    }
_361    if (tc.currentChannel.sid === tc.generalChannel.sid) {
_361      alert('You cannot delete the general channel');
_361      return;
_361    }
_361    tc.currentChannel.delete().then(function(channel) {
_361      console.log('channel: '+ channel.friendlyName + ' deleted');
_361      setupChannel(tc.generalChannel);
_361    });
_361  }
_361
_361  function selectChannel(event) {
_361    var target = $(event.target);
_361    var channelSid = target.data().sid;
_361    var selectedChannel = tc.channelArray.filter(function(channel) {
_361      return channel.sid === channelSid;
_361    })[0];
_361    if (selectedChannel === tc.currentChannel) {
_361      return;
_361    }
_361    setupChannel(selectedChannel);
_361  };
_361
_361  function disconnectClient() {
_361    leaveCurrentChannel();
_361    $channelList.text('');
_361    tc.$messageList.text('');
_361    channels = undefined;
_361    $statusRow.addClass('disconnected').removeClass('connected');
_361    tc.$messageList.addClass('disconnected').removeClass('connected');
_361    $connectPanel.addClass('disconnected').removeClass('connected');
_361    $inputText.removeClass('with-shadow');
_361    $typingRow.addClass('disconnected').removeClass('connected');
_361  }
_361
_361  tc.sortChannelsByName = function(channels) {
_361    return channels.sort(function(a, b) {
_361      if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return -1;
_361      }
_361      if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_361        return 1;
_361      }
_361      return a.friendlyName.localeCompare(b.friendlyName);
_361    });
_361  };
_361
_361  return tc;
_361})();

That's it! We've just implemented a simple chat application for PHP using Laravel.

Where to Next?

If you are a PHP developer working with Twilio, you might want to check out these other tutorials:

Click-To-Call

Put a button on your web page that connects visitors to live support or salespeople via telephone.

Automated Survey

Instantly collect structured data from your users with a survey conducted over a voice call or SMS text messages.

Did this help?

Thanks for checking out this tutorial! If you have any feedback to share with us, we'd love to hear it. Tweet @twilio to let us know what you think.