How to implement read receipts in Sendbird Chat

fetch_channels.js

sb.GroupChannel.getChannel(CHANNEL_URL, function(groupChannel, error) {
    if (error) {}
    groupChannel.markAsRead()
});

get_read_member_result.json

[
  {
    "nickname": "UserA",
    "plainProfileUrl": "https://static.sendbird.com/sample/user_sdk/user_sdk_04.png",
    "userId": "UserA",
    "connectionStatus": "online",
    "lastSeenAt": 0,
    "metaData": {
      "marriage": "N",
      "location": "Washingtonx",
      "hasSomeone": "Y"
    },
    "isActive": true,
    "friendDiscoveryKey": null,
    "friendName": null,
    "_preferredLanguages": null,
    "requireAuth": false,
    "state": "joined",
    "role": "none",
    "isMuted": false,
    "isBlockedByMe": false,
    "isBlockingMe": false
  }
]

get_read_members.js

var sb = new SendBird({appId: APP_ID});
var channelHandler = new sb.ChannelHandler();

channelHandler.onReadReceiptUpdated = function(groupChannel) {
       
       //For each message in the message view
	var readMembers = groupChannel.getReadMembers(MESSAGE);
};
sb.addChannelHandler(UNIQUE_HANDLER_ID, channelHandler);

load_previous_message.js

// There should only be one single instance per channel view.
var listQuery = groupChannel.createPreviousMessageListQuery();
var myMessageObjects = []
// Retrieving previous messages.
listQuery.load(function(messages, error) {
    if (error) {}
    // Retrieving previous messages.
    messages.forEach(message => {
       const readMembers = groupChannel.getReadMembers(message);
       myMessageObjects.push(
          {
          message: message,
          readMembers: readMembers
          }
       )
    })
 });

on_message_received.js

var sb = new SendBird({appId: APP_ID});
var channelHandler = new sb.ChannelHandler();

channelHandler.onMessageReceived = function(channel, message) {
    //if message view is visible and user is shown the message incoming message
    channel.markAsRead()
};

// Add this channel event handler to the `SendBird` instance.
sb.addChannelHandler(UNIQUE_HANDLER_ID, channelHandler);

refresh_channel.js

groupChannel.refresh(function(response, error) {
    if (error) {}
   groupChannel.markAsRead()
});

send_message.js

const params = new sb.UserMessageParams();
params.message = TEXT_MESSAGE;

groupChannel.sendUserMessage(params, function(userMessage, error) {
    if (error) {}
    groupChannel.markAsRead()
    const messageId = userMessage.messageId;
});