SIP.Transport

SIP.js Transport provides a parent class in which an implementation transport layer is built on top of. This layer handles the actual sending and receiving of SIP requests and responses.

• Construction
• Instance Methods
  • send(msg)
  • sendPromise()
  • connect()
  • connectPromise()
  • disconnect()
  • disconnectPromise()
  • isConnected()
  • afterConnected()
• Events
  • connected
  • disconnected
  • messageSent
  • message
  • transportError

Construction

The construction of a transport is not meant to be done manually. Instead, SIP.js user agents create a transport to use for themselves. As of 0.11.0, transport in SIP.js represents a generic layer upon which an implementation is built, with websockets being the default. A transport implementation can be specified in the UA passing in the constructor as the transportConstructor configuration option. Any configuration options required for the transport layer will be passed in as the transportOptions UA configuration option.

When constructed, the UA will assign the new Transport as its own transport property before automatically attempting to connect (configurable by ua.configuration.autostart).

Instance Methods

send(msg)

Send a message and automatically emits a messageSent event. Implementation delegated to abstract method sendPromise.

Parameters

Name	Mandatory?	Type	Description
msg	Yes	SIP.OutgoingRequest | String	A SIP Request (represented as a String or SIP.OutgoingRequest) to send along the WebSocket.
options	No	Object	Object to pass to sendPromise()

Returns

Promise

sendPromise()

Abstract Implementation of sending a message over the transport. MUST return a promise that resolves with an object with mandatory parameter msg and optional parameter overrideEvent.

Parameters

Name	Mandatory?	Type	Description
msg	Yes	SIP.OutgoingRequest | String	A SIP Request (represented as a String or SIP.OutgoingRequest) to send along the WebSocket.
options	No	Object	Options to pass to the implementation

Returns

Promise that resolves with an object with 2 parameters, overrideEvent and msg.

Name	Mandatory?	Type	Description
msg	Yes	String	A SIP Request (represented as a String or SIP.OutgoingRequest) to send along the WebSocket.
overrideEvent	No	Boolean	If set to true, the default messageSent event emitted by send() will not be emitted. If you override the event in this fashion, you SHOULD emit it in your implementation of sendPromise()

connect()

Connects the transport and automatically emits a connected event. Implementation is delegated to abstract method connectPromise().

Parameters

Name	Mandatory?	Type	Description
options	No	Object	Object to pass to connectPromise()

Returns

Promise

connectPromise()

Abstract Implementation of connecting the transport. Called by connect(). MUST return a promise that resolves with an object.

Returns

Promise that resolves with an object with properties:

Name	Mandatory?	Type	Description
overrideEvent	No	Boolean	If set to true, the default connected event emitted by connect() will not be emitted. If you override the event in this fashion, you SHOULD emit it in your implementation of connectPromise()

disconnect()

Disconnects the transport and automatically emits a disconnected event. Implementation is delegated to abstract method disconnectPromise().

Parameters

Name	Mandatory?	Type	Description
options	No	Object	Object to pass to disconnectPromise()

Returns

Promise

disconnectPromise()

Abstract Implementation of disconnecting the transport. Called by disconnect(). MUST return a promise that resolves with an object.

Returns

Promise that resolves with an object with properties:

Name	Mandatory?	Type	Description
overrideEvent	No	Boolean	If set to true, the default disconnected event emitted by disconnect() will not be emitted. If you override the event in this fashion, you SHOULD emit it in your implementation of disconnectPromise()

isConnected()

Abstract

Returns

Type	Description
Boolean	true if the connection is established, false otherwise

afterConnected()

If the transport is connected, the callback is executed immediately- otherwise sets up a once listener on own connected event supplying the given callback. Checks connection state via own isConnected() method.

Parameters

Name	Type	Description
callback	Function	A callback to be executed

Events

Transport objects extend the SIP.EventEmitter interface. Each event emitted by the transport passes specific relevant arguments to its callbacks. Additional events MAY be added for child implementations.

connected

Fired when the connection is established.

on('connected', function () {})

There are no documented arguments for this event.

disconnected

Fired when the connection is interrupted or lost

on('disconnected', function () {})

There are no documented arguments for this event.

messageSent

Fired when a message is sent over the transport

on('messageSent', function (message) {})

Arguments

message - String - The message that was sent

message

Fired when a message is received over the transport

on('message', function (message) {})

Arguments

message - String - The message that was received

transportError

Fired when an error occurs in the transport layer and other layers need to be notified

on('transportError', function () {})

There are no documented arguments for this event.