Composite Client Command Reference¶

This is a companion guide for using the Composite Client, found here.

Methods¶

Constructor¶

The global Composite constructor. Takes no config options and is used for instantiation purposes.

var app = new Composite();

connect:function (string:url)¶

Connects to the Composite service. The handshake is over HTTP, so a good example would be:

app.connect('http://localhost:8081/composite');

on:function (string:event, function:callback)¶

Registers an event handler for a given event.

app.on('app_start', function(){ start_your_app(); });

The following are valid events (Automatic denotes that the event is triggered internally, whilst Manual requires a client-triggered action):

Property	Description
`init`	Fires after a successful connect and a valid UUID has been assigned. Automatic.
`synced`	Fires once the app has determined the average latency between it and the service. Automatic.
`app_start`	Fires after the `host` device in the same session queries the `start` endpoint. Manual.
`app_end`	Fires after the `host` device in the same session queries the `end` endpoint. Manual.
`session_joined`	Fires after a successful `join` query and only to the client that queried it. Manual.
`device_update`	Fires after a new device has joined the session. Manual
`device_disconnect`	Fires if a device in the session suddenly disconnects. Manual.
`data`	Fires when a client sends a payload to the `data` endpoint. Manual.
`update`	Fires when a client sends a payload to the `update` endpoint. Manual.

off:function (string:event, function:callback)¶

Removes an event handler for a given event.

app.off('app_start', function(){ start_your_app(); }); // Must pass the function you called earlier

syncTime:function¶

Sends a message to the service with the current time in order to determine latency. This also happens automatically, but is exposed in case your application needs to check more frequently.

app.syncTime()

join:function (object)¶

Sends a join request to the service to get a session, requires that the client has already set its location (lat/lon) under the location array (see location).

The Object passed can have the following parameters: - type: String ‘enter’ or ‘exit’. Defaults to ‘exit’. - geo: Array with two elements corresponding to a devices longitude/latitude. Defaults to the local lon/lat if not present.

app.join({type: 'exit', geo: [0.1234123, 1.123123]});

sendData:function (object)¶

Sends a message to all clients in the same session with a data payload. The passed object is the payload you wish to send to all clients. Requires that clients have ``join``ed successfully prior to sending.

app.sendData({ ballPosition: [103, 234], ballSpeed: 23, activeDevice: 2 });

sendUpdate:function (object)¶

Sends a message to all clients in the same session with a data payload. The passed object is the payload you wish to send to all clients. Requires that clients have ``join``ed successfully prior to sending.

app.sendUpdate({ ballPosition: [103, 234], ballSpeed: 23, activeDevice: 2 });

startApp:function¶

Triggers the app_start event in all other clients. Must be the “host” client to trigger (see host below).

app.startApp()

endApp:function¶

Triggers the app_end event in all the other clients. Must be the “host” client to trigger (see host below).

app.endApp();

disconnect:function¶

Disconnects cleanly from the Composite service. Other clients in the same session will be notified of the disconnect.

app.disconnect()

Properties¶

connected¶

Type: boolean

Container indicating if the client is connected to the composite service.

app.connected; // true if connected, false if not

uuid¶

Type: string

The UUID of the device given from the service, can be used as a way to find the device(s) order.

app.uuid; // "7040550a-3834-4974-a19c-c7d39749a7e5"

timeDifference¶

Type: number

The median time difference between the client’s Date.now and the services Date.now.

app.timeDifference; // 1121

latency¶

Type: number (milliseconds)

The average time it takes to send and receive a message through composite. Updated periodically throughout the application.

app.latency; // 10

host¶

Type: boolean

If the device is the host device. This is determined by order join``ed, and the first device to join is given ``host privileges. This is updated during the device_update event as it’s possible for the host to drop connection. host``s can trigger the ``app_start and app_end events.

app.host; // true

location¶

Type: array[float]

The container for the devices geographic position in the form of [{latitude}, {longitude}]. Location is not captured automatically, and must be implemented manually, and is used for session management.

Example:

navigator.geolocation.getCurrentPosition(function(position) {
    // Setting the position
    app.location = [position.coords.latitude, position.coords.longitude];
});

app.location; // [45.523452, -122.67620699999999]

session¶

Type: string

The session the device is currently a part of. This is set automatically after successfully join``ing, and is required when broadcasting ``update``s and ``data.

app.session; // "7040550a-3834-4974-a19c-c7d39749a7e5"

active¶

Type: boolean If the app is currently in the start state. This happens automatically after the app_start event and is set to false after the app_end event.

app.active; // true