Number

Number

The <Number> noun specifies a phone number to dial. You can use multiple <Number> nouns within a <Dial> verb to simultaneously call all of them at once. The first call to pick up is connected to the current call and the rest are hung up.

Number Attributes

Name Allowed Values Default Value

sendDigits

any digits

none

url

any url

none

method

GET, POST

POST

statusCallbackEvent

initiated, ringing, answered, completed

none

statusCallback

any url

none

statusCallbackMethod

GET, POST

POST

  • sendDigits. The 'sendDigits' attribute tells Restcomm to play DTMF tones when the call is answered. This is useful when dialing a phone number and an extension. Restcomm will dial the number, and when the automated system picks up, send the DTMF tones to connect to the extension.

  • url. The 'url' attribute allows you to specify a url for a RCML document that will run on the called party’s end, after he/she answers, but before the parties are connected. You can use this RCML to privately play or say information to the called party, or provide a chance to decline the phone call using <Gather> and <Hangup>. The current caller will continue to hear ringing while the RCML document executes on the other end. RCML documents executed in this manner are not allowed to contain the <Dial> verb.

method

The 'method' attribute allows you to specify which HTTP method Restcomm should use when requesting the URL in the 'url' attribute. The default is POST.

statusCallbackEvent

When dialing out to a PSTN Number using <Dial>, an outbound call is initiated. The call transitions from the initiated state to the ringing state when the phone starts ringing. It transitions to the answered state when the call is picked up, and finally to the completed state when the call is over. With statusCallbackEvent, you can subscribe to receive webhooks for the different call progress events: initiated, ringing, answered, or completed for a given call.

The statusCallbackEvent attribute allows you to specify which events Restcomm should webhook on. To specify multiple events separate them with a comma: initiated,ringing,answered,completed. If a statusCallback is provided and no status callback events are specified the completed event will be sent by default.

As opposed to creating an outbound call via the API, outbound calls created using <Dial> are initiated right away and never queued. The following shows a timeline of possible call events that can be returned and the different call statuses that a <Dial> leg may experience:

The <Number> noun specifies a PSTN Number to dial. You can use multiple <Number> nouns within a <Dial> verb to simultaneously attempt a connection with many numbers at once. The first number to accept the incoming connection is connected to the call and the other connection attempts are canceled.

Outbound Dial call events diagram
Event Description

initiated

The initiated event is fired when Restcomm starts dialing the call.

ringing

The ringing event is fired when the call starts ringing.

answered

The answered event is fired when the call is answered.

completed

The completed event is fired when the call is completed regardless of the termination status: busy, canceled, completed, failed, or no-answer. If no statusCallbackEvent is specified, completed will be fired by default.

statusCallback

The statusCallback attribute allows you to specify a URL for Restcomm to send webhook requests to on each event specified in the statusCallbackEvent attribute.

statusCallbackMethod

The statusCallbackMethod attribute allows you to specify which HTTP method Restcomm should use when requesting the URL in the statusCallback attribute. The default is POST.

Status Callback HTTP Parameters

The parameters Restcomm passes to your application in its asynchronous request to the StatusCallback URL include all parameters passed in a synchronous request to retrieve RCML when Restcomm receives a call to one of your Restcomm numbers. The full list of parameters and descriptions of each are in the RCML Voice Request documentation.

When the call progress events are fired, the Status Callback request also passes these additional parameters:

Parameter Description

CallSid

A unique identifier for this call, generated by Restcomm. You can use the CallSid to modify the child call by POSTing to Calls/{CallSid} with a new RCML URL.

CallStatus

A descriptive status for the call. The value is one of queued, initiated, ringing, in-progress, busy, failed, or no-answer. See the CallStatus section for more details.

CallDuration

The duration in seconds of the just-completed call. Only present in the completed event.

Timestamp

The timestamp when the event was fired, given as UTC in RFC 2822 format.

CallbackSource

A string that describes the source of the webhook. This is provided to help disambiguate why the webhook was made. On Status Callbacks, this value is always call-progress-events.

SequenceNumber

The order in which the events were fired, starting from 0. Although events are fired in order, they are made as separate HTTP requests and there is no guarantee they will arrive in the same order.

Including propietary SIP headers

This noun allows to customize propietary SIP headers to be included in the outgoing SIP message. Those will be include following SIP URI params syntax. See example below.

Examples

For an example of how to use the <Number> noun see below.

<Response>
    <Dial>
    <Number sendDigits="wwww1234">1-444-555-6666</Number>
    </Dial>
</Response>

Dialing with propietary SIP headers

<Response>
    <Dial>
    <Number sendDigits="wwww1234">1-444-555-6666?X-Custom-Header1=1234&X-Custom-Header2=4321</Number>
    </Dial>
</Response>