opentok.js

chat.html.erb

<%= form_tag '#', class: 'chat_form' do %>
   <%= text_field_tag ‘message’, id: ‘chat_msg’%>
   <%= submit_tag ‘send’%>
<% end %>

<script src='//static.opentok.com/v2/js/opentok.min.js'></script>
<script type="text/javascript">
 $(document).ready(function(){
   var apiKey = <%= OPENTOK_API_KEY %>
   // use same session_id and token that we have generated above.
   var sessionID = "<%= @session_id %>"
   var token = "<%= @token %>"

   var session = OT.initSession(apiKey, sessionID);
   session.connect(token, function(error) {
     if (error) {
       console.log('Unable to connect: ', error.message);
     }
     else {console.log('Connected to the session.');}
   }); 

   // send message to text_chat channel using signal method on form submit
   $(".chat_form").submit(function(event) {
      event.preventDefault();
      if($('#chat_msg').val() != ""){
         session.signal({
            data:$('#chat_msg').val(),
            type:"text_chat"
            },
            function(error) {
              $('#chat_msg').val('');
            }
          );
      }
   });

   // listen for the signal on text_chat channel
   // in order to receive message sent to channel text_chat
   session.on('signal:text_chat', function(event) {
      message = event.data
      // do some stuff here with message,
      // maybe show in chat window/store in database if needed
   });

});