You can choose from two methods for retrieving the history of a channel. They return the history(if available) in JSON format with message timestamp.
If you do not wish to receive the timestamp of each message, set
false. By default, it is set to
50 latest messages will be returned from the server with their respective timestamps.
cometClient.getHistory(groupChannel, "count", 50, true);
Messages from the given timestamp till date will be returned without their respective timestamps.
cometClient.getHistory(groupChannel, "timestamp", 1354735353657, false);