Ajax, long-polling, multi users, chat arrived

0
votes

lets have a "complex" site, there are three modules: "links", "home", "chat". Links, home just a static-like page, no need long polling, it doesnt even start. But in case "chat" any time a new message may arrive from other users, and I want to immediatly show it, without refreshing the site.

So, in "chat" a long-polling was started, and it detects that a new chat message arrived, so poll-requests finishes and sends a "send the chatbox-div" message - so that site may refresh the DIV.

But lets imagine three users are watching this module right now. How to notice all of them to refresh the content?

EDIT: how I imagine: lets somewhere save a flag which indicates that the message arrived, and the long polling request is watching this flag. If it changes, get the message, and zero that flag - but then its possible some users (some requests) wont notice that

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javascriptphpjqueryajax
With long polling, the client checks the server periodically using AJAX for fresh content and once received, the new content is simply appended to the div. No need to refresh the page – Kneel-Before-ZOD
I edited the question, to make it more clear – John Smith
Is there any reason you don't want the long polling to automatically update the div with the new content? It seems more efficient. But yeah, you can create a flag if you want. It's all possible. – Kneel-Before-ZOD

1 Answers

1
votes

Senario : One Server; N Clients in the same Chanel

The server implements a Pool for one chanel;
Pool is configured as follow (it can be an array/class/...) :
ID(Integer/string)
=> A new record is inserted if a client made a connection and it will be identified by his ID
=> This record will be deleted, if the client do deconnection or exit from this chanel
MESSAGES(String) : New Messages must be concatenated to the old that are already stored on the pool

Each Time that a client send a new message to the server
1 - All MESSAGES of the pool will be updated by concatenation unread messages by the new one (except for the sender)

Each Time that the client make a request to the server (using Ajax Long Pooling)
1 - the server will deliver him the right MESSAGE basing on his ID
2 - Erase MESSAGE

With this implementation, client can receive an empty message, so on front-end you have to do the appropriate operation