The Main of NowJS functionality lies from the now object. The now item is Specific because it exists to the server as well as the shopper.
What this means is variables you established within the now item are instantly synced concerning the customer and the server. Also server features may be specifically referred to as over the consumer and shopper features can be named directly from the server.
You may have a working HTTP server up and jogging in NodeJS with just a few strains of code. For instance:
var http = have to have('http');
http.createServer(perform (req, res)
res.writeHead(two hundred, 'Material-Style': 'text/simple');
res.stop('Good day Worldn');
).pay attention(8080);
This minimal snippet of code will develop an HTTP server, hear on port 8080, and deliver again "Hi there Earth" for every ask for. That's it. Practically nothing more essential.
Using NowJS, conversation concerning the consumer and server facet is just as uncomplicated.
Client Aspect:
In this code snippet, the consumer facet sets a variable to 'someValue' and calls serverSideFunction(), that's declared only on the server.
Server Aspect:
Anyone.now.serverSideFunction = perform()
console.log(this.now.clientSideVariable);
The server facet is then capable of obtain clientSideVariable, that is declared only on the consumer.
All the main points like developing connections and speaking alter of information between the server and consumer are handed automagically because of the framework.
In fact composing code applying this framework is so easy, the NowJS hi environment instance can be a working chat consumer and server prepared in less than a dozen lines of code. Go test it out.
As a straightforward physical exercise to acquire at ease with the NowJS API, we will modify the chat shopper example to help a number of chat rooms. Let us take a look at how straightforward it can be.
Server Side (multiroom_server.js)
1. The first thing we must do is modify the distributeMessage() function to only deliver messages to end users in a similar chat home since the user.
// Send out information to Everybody while in the users team
All people.now.distributeMessage = function(message)
var group = nowjs.getGroup(this.now.serverRoom);
team.now.receiveMessage(this.now.identify+'@'+this.now.serverRoom, information);
;
We store the title in the server place to the shopper side (this.now.serverRoom). Once the customer phone calls the distributeMessage() functionality we send the message to Every person in precisely the same chat area through the use of getGroup() and utilizing the team.now item rather than theeveryone.now object. (everyone is just a bunch which contains all people linked to the server).
2. Subsequent we have to take care of the customer transforming chat rooms.
Anyone.now.changeRoom = function(newRoom)
var oldRoom = this.now.serverRoom;
//if previous area is just not null; then go away the aged home
if(oldRoom)
var oldGroup = nowjs.getGroup(oldRoom);
oldGroup.removeUser(this.user.clientId);
// join the new space
var newGroup = nowjs.getGroup(newRoom);
newGroup.addUser(this.consumer.clientId);
// update the customer's serverRoom variable
this.now.serverRoom = newRoom;
;
The getGroup() system fetches the team item if it exists and makes a group if it doesn't already exist. We use the groups addUser() and removeUser() ways to transfer the customer through the outdated place to The brand new home.
Which is over it on the server side.
Client Side (multiroom.html)
3. Initial we include a drop down Together with the listing of server rooms.
four. Future we connect with the server facet changeRoom() functionality modular vault room in the event the person initially connects and Any time the fall down is adjusted.
// on creating 'now' relationship, established the server place
now.All set(purpose()
// By default decide the 1st chatroom
now.changeRoom($('#server-place').val());
);
// On transform of drop down, clear text and alter server home
$('#server-home').transform(purpose()
$("#messages").html(");
now.changeRoom($('#server-place').val());
);
five. For further credit rating, we will allow the server to dynamically supply the list of rooms when the client connects.