Fax XML

import Tabs from @theme/Tabs; import TabItem from @theme/TabItem; Fax cXML is a set of actions defined in an XML document you can use to tell SignalWire what to do when you receive an incoming fax. ## Overview When a fax is sent to one of your SignalWire phone numbers, SignalWire looks up the Fax cXML document from the URL you configured, and reads the instructions you provided to determine what to do. Fax cXML allows you to control what SignalWire will do when you receive an incoming fax. ## Request SignalWire makes an HTTP request to your configured endpoint just like a regular web form submission (POST) or page load (GET). The request includes contextual information about the fax, allowing you to respond dynamically and fluidly to the fax to meet the needs of your application. You can configure the endpoint URL and HTTP Method in your phone number settings panel on your SignalWire Dashboard, or via the REST API. ## Request Parameters SignalWire sends the following parameters, as either URL query parameters or POST parameters, to your endpoint when it receives a fax: | Parameter | | | --: | - | | FaxSid string | A unique identifier for the fax. | | AccountSid string | The account that the fax was sent from. | | To string | The number or SIP URI the fax will be sent to. | | From string | The number or SIP URI the fax was sent from. | | ApiVersion string | The version of the SignalWire API. | ## Responding to SignalWire An example of a cXML document that receives an incoming fax: xml javascript const { RestClient } = require(@signalwire/compatibility-api); const response = new RestClient.LaML.FaxResponse(); response.receive({ action: /fax/received }); console.log(response.toString()); csharp using Twilio.TwiML; using Twilio.TwiML.Fax; using System; class Example { static void Main() { var response = new FaxResponse(); response.Receive(action: /fax/received)); Console.WriteLine(response.ToString());; } } python from signalwire.fax_response import FaxResponse, Receive response = FaxResponse() response.receive(action=/fax/received) print(response) ruby require signalwire/sdk response = Signalwire::Sdk::FaxResponse.new do |response| response.receive(action: /fax/received) end puts response.to_s When a fax comes into one of your SignalWire phone numbers, SignalWire makes an HTTP request to the URL endpoint you configured for that number. Your response to that request instructs SignalWire on what to do next. Responses to the HTTP request are in SignalWire cXML. SignalWire starts at the top of your XML document and executes your commands in order, from top to bottom. :::info cXML verbs and their attributes are case-sensitive, so using instead of will result in an error. ::: ### StatusCallback when sending a fax When sending a fax you can specify a StatusCallback URL. If you do so, your specified URL will receive POST requests with the following parameters: | Parameter | | | -: | | | RemoteStationId optional | The transmitting subscriber identification (TSID) reported by the fax machine that sent in the fax. | | FaxStatus optional | The status of the fax. | | OriginalMediaUrl optional | The original URL passed when a fax is sent. | | NumPages optional | The number of pages received from a successful fax. | | MediaSid optional | The [SID](/guides/what-is-a-sid/) that uniquely identifies the fax media. | | MediaUrl optional | The media URL to request to retrieve incoming media. | | ErrorCode optional | The error code provides more information on a failed fax. | | ErrorMessage optional | The message explaining the reason for fax failure. |