UAS API - Outbound Connect Sample Application

• Python
• C#
• VB
• F#

• Filename:

  samples/outbound_connect.py

  Description:

  An outbound application that makes calls to two destination addresses and connects them together. The destination addresses are supplied in the outbound_parameters variable, using the semi-colon (;) as a delimiter. This application also requires one extra channel.

  First the two call destination addresses are extracted from outbound_parameters using Python's split() function. Then the extra channel is retrieved from the channel.ExtraChannel list. Extra channels are set on the Inbound and Outbound Services pages.

  The application places two calls and the calling code has been put in a function called _place_call, which takes a channel, destination address and call_from as parameters. The call_from variable identifies the calling party and its value is taken from application_parameters which is configured on the Outbound Services page.

  The first outbound call is placed and, if successful, TTS is used to ask the user to speak a message after the beep. To create a beep, a DTMF tone is played using the channel.DTMFPlayer.play() function. The message is recorded and then the caller is asked to hold while the system calls the second destination..

  The extra channel is used to call the second destination and the recorded message from the first call is played using the channel.FilePlayer.start() function which does not block. This allows the application to use TTS to tell the first caller that his message is being played.

  Once the message has been played, the application joins the two calls together using the channel.connect() function, this allows the two calls to communicate with each other. The application then waits for either party to hang up, using the channel.state() function on each channel.

  Code:

  """
      An outbound application that makes calls to two destination addresses 
      (passed in through outbound_parameters using the semi-colon as a 
      delimiter). 
  
      It prompts the first call to record a message and plays this to the 
      second call before connecting the two calls together. It then waits for 
      the calls to be hung up. 
  
      This application requires that call_from is supplied in 
      application_parameters and it requires one extra channel (this is 
      configured on the outbound service page of the CWP). 
  
      For information on placing outbound calls please read the online 
      web services documentation.
      
      For additional information regarding outbound PSTN calls, please see the 
      online documentation.
      
      Also have a look at the invoke_outbound_service sample code in the 
      samples_ws directory.
  
      Actions:
          - place an outbound call
          - record a message
          - place another outbound call
          - play the message to the outbound call
          - connect the two calls together
          - wait for someone to hang up
  
  """
  
  from prosody.uas import Hangup, Error, ICanRun
  import time
  
  __uas_version__  = "0.0.1"
  __uas_identify__ = "application"
  
  
  def _place_call(channel, destination, call_from):
          # Place an outbound call. If the destination is BUSY,
          # wait ten seconds and try again; try for one minute.
          endTime = time.time() + 60
  
          while channel.call(destination, call_from=call_from) != channel.State.ANSWERED:
              cause = channel.cause()
              if cause != channel.Cause.BUSY:
                  raise Error("Call destination returned cause {0}".format(cause))
              if time.time() > endTime:
                  raise Hangup("Call destination is busy.")
              time.sleep(10)
              continue
  
          
  def main(channel, application_instance_id, file_man, my_log, application_parameters, outbound_parameters):
      try:
          return_code = 0
          out_channel_2 = None
          # read the outbound args, we're expecting two destination_address with a ; as delimiter
          my_log.info("Out Args: {0}".format(outbound_parameters))
          
          out_arg_splits = outbound_parameters.split(';')
          try:
              outbound_destination_1 = out_arg_splits[0]
              outbound_destination_2 = out_arg_splits[1]
              # we expect the call_from details to be in application_parameters
              # this is used in CLI validation for PSTN calls
              call_from = application_parameters
          except:
              raise Error("Could not get outbound call destinations.")
          
          # get the extra channel
          try:
              out_channel_2 = channel.ExtraChannel[0]
          except:
              raise Error("You need to register an extra channel for this application")
  
          #place the first call
          _place_call(channel, outbound_destination_1, call_from)
          
          my_log.info("Placed first outbound call")
  
          # prompt the party to record a message, the prompt is played using TTS
          cause = channel.FilePlayer.say("<acu-engine name='Polly'><voice name='Brian'>Hello, please record a message after the beep.</voice></acu-engine>")
          if cause != channel.FilePlayer.Cause.NORMAL:
              raise Error("Say hello failed: cause is {0}".format(cause)) # log at error level
  
          # play a DTMF digit for the tone
          cause = channel.DTMFPlayer.play('#')
          if cause != channel.DTMFPlayer.Cause.NORMAL:
              raise Error("Play # failed: cause is {0}".format(cause))
          
          # record the message, record until we've had three seconds of silence
          cause = channel.FileRecorder.record('recorded_message_{0}.wav'.format(application_instance_id), milliseconds_max_silence=3000)
          if cause != channel.FileRecorder.Cause.SILENCE:
              raise Error("Record message failed: cause is {0}".format(cause)) # log at error level        
  
          # thanks for the recording
          cause = channel.FilePlayer.say("Thank you, please wait while I phone a friend.")
          if cause != channel.FilePlayer.Cause.NORMAL:
              raise Error("Say thank you failed: cause is {0}".format(cause)) # log at error level
          
          # place next call
          _place_call(out_channel_2, outbound_destination_2, call_from)
              
          # We have an outbound call, start playing the recording to the outbound call
          if out_channel_2.FilePlayer.start('recorded_message_{0}.wav'.format(application_instance_id)) is False:
              raise Error("Failed to start playing recording to outbound channel")
          
          # tell the inbound channel what we're doing
          cause = channel.FilePlayer.say("I am playing your message to your friend.")
          if cause != channel.FilePlayer.Cause.NORMAL:
              raise Error("Say playing to friend failed: cause is {0}".format(cause))
          
          # wait for message play to complete
          cause = out_channel_2.FilePlayer.wait_until_finished()
          if cause != out_channel_2.FilePlayer.Cause.NORMAL:
              raise Error("Wait for finished failed: cause is {0}".format(cause))
  
          # indicate to the far end that the message has finished playing
          cause = out_channel_2.DTMFPlayer.play('#')
          if cause != out_channel_2.DTMFPlayer.Cause.NORMAL:
              raise Error("DTMF play returned {0}: expected {1}".format(cause, out_channel_2.DTMFPlayer.Cause.NORMAL))
              
          # let the parties talk to each other
          if channel.connect(out_channel_2) is True:
              # wait until either call hangs up
              # wait on i_can_run to prevent an accidental infinite loop
              i_can_run = ICanRun(channel)
              while i_can_run:
                  # throw hangup exception on IDLE
                  channel.state(check_for_hangup=True)
                  out_channel_2.state(check_for_hangup=True)
                  time.sleep(1)
          else:
              raise Error('Connect channels failed')
              
      except Hangup as exc:
          my_log.info("Hangup exception reports: {0}".format(exc))
           # in this app a hangup is not an error, return a positive value
          return_code = 100
          
      except Error as exc:
          # for error conditions return a negative value
          my_log.error("Error exception reports: {0}".format(exc))
          return_code = -101
          
      except Exception as exc:
          # an unexpected exception, return a negative value
          my_log.exception("Unexpected exception reports: {0}".format(exc))
          return_code = -102
          
      finally:
          if channel is not None:
              if channel.state() != channel.State.IDLE:
                  channel.hang_up()
          if out_channel_2 is not None:
              if out_channel_2.state() != out_channel_2.State.IDLE:
                  out_channel_2.hang_up()
      return return_code
  

• Filename:

  Samples\C#\OutboundConnect\OutboundConnect.cs

  Description:

  In this application we extract two call destination addresses from the outboundParameters argument using the String.Split() method and then ensure we have at least one extra channel available. This will allow us to make one outbound call on the primary channel (the channel argument) and one outbound call on an extra channel.

  If either of the destination addresses are PSTN numbers then the source address (caller Id) that is passed into the application via the applicationParameters argument must be set to a PSTN number that has been validated from the Caller Id page on cloud.aculab.com.

  We call the first destination address on the primary channel using the channel.Call() method and when answered, we use TTS to ask the callee to record a message that will ultimately be played to the second callee. We can record a message using the channel.FileRecorder.Start() method. This requires a filename as a parameter to identify where to store the recorded data. To play a message prompt, we use the channel.DTmfPlayer.Play() method. We wait for silence from the other end for a couple of seconds before ending the recording.

  We then call the second destination address on one of the extra channels and when answered, we play the previously recorded message to the second callee. Then we use TTS to notify both callees that they are being connected and use the Connect() method to connect both calls together bidirectionally. To wait for either caller to hangup, we use the channel.WaitForIdle() method.

  Code:

  using System;
  using System.Threading;
  using AMSClassLibrary;
  using UASAppAPI;
  
  // An outbound application that makes calls to two destination addresses (passed in).
  // It prompts the first call to record a message and plays this to the second call 
  // before tromboning the two calls together. It then waits for the calls to be hung up.
  //
  // The Caller Id (callFrom) that is to be used when calling out should be supplied in
  // the applicationsParameters field. For outgoing SIP calls this can be empty, but for
  // outgoing PSTN calls see the Outbound Calls documentation for your platform.
  //
  // Requires:
  // [outboundParameters = two destination addresses for the two outgoing calls, semicolon delimited]
  // [applicationParameters = an optional validated Caller Id]
  // [1 extra channels]
  //
  // e.g.
  // outboundParameters = "sip:bob@bobscompany.com;sip:brian@brianscompany.com"
  // applicationParameters = ""
  // or
  // outboundParameters = "441908081876;441908678180"
  // applicationParameters = "441908876543"
  //
  namespace OutboundConnect
  {
      // The application class.
      // This must have the same name as the assembly and must inherit from either 
      // UASInboundApplication or UASOutboundApplication.
      // It must override the Run method.
      public class OutboundConnect : UASOutboundApplication
      {
          // Possible return codes
          enum ReturnCode
          {
              // Success Codes:
              Success = 0,
              // ... any positive integer
  
              // Fail Codes:
              // -1 to -99 reserved
              ExceptionThrown = -100,
              ArgumentError = -101,
              NoCallerIdError = -102,
              NotSufficientExtraChannels = -103
          }
  
          // This is the entry point for the application
          public override int Run(UASCallChannel channel,
                                  string applicationParameters, // Caller Id (may be required for outgoing PSTN, optional for outgoing SIP)
                                  string outboundParameters)    // 2 x destinationAddresses, semicolon delimited...
          {
              this.Trace.TraceInfo("Start - appParms [{0}] outParms [{1}]",
                                 applicationParameters,
                                 outboundParameters);
              ReturnCode reply = ReturnCode.Success;
  
              UASCallChannel otherChannel = null;
              string recFileName = "recordings/introMessage";
  
              try
              {
                  // Typically the outboundParameters field is simply the destination address.
                  // However, in this case we require 2 destination addresses to be specified.
                  string[] destinationAddress = outboundParameters.Split(';');
                  if (destinationAddress.Length < 2)
                  {
                      reply = ReturnCode.ArgumentError;
                      this.Trace.TraceError("This app requires 2 destination addresses in the outboundParameters field");
                  }
  
                  // Check we've got an extra Channel
                  if (reply == ReturnCode.Success)
                  {
                      if (channel.ExtraChannels.Length < 1)
                      {
                          this.Trace.TraceError("This app requires at least 1 extra channel to be configured");
                          reply = ReturnCode.NotSufficientExtraChannels;
                      }
                  }
  
                  // Make the first call on the primary channel
                  if (reply == ReturnCode.Success)
                  {
                      string callFrom = applicationParameters;
                      CallState state = channel.Call(destinationAddress[0], callFrom);
                      if (state == CallState.Answered)
                      {
                          // Record an introduction message
                          channel.FilePlayer.Say("Hello." +
                                                 "Please record an introduction message for " +
                                                 destinationAddress[1] +
                                                 "after the tone." +
                                                 "Press any digit to stop the recording.");
  
                          Thread.Sleep(1000);
  
                          // Start recording, enabling barge in
                          channel.FileRecorder.Start(recFileName, true);
  
                          // Play a tone to signal that recording has started
                          channel.DtmfPlayer.Play("0");
  
                          // Wait for a period for recording to complete (10 seconds of silence) 
                          // or the call to have been hung up
                          FileRecorderCause recCause = channel.FileRecorder.WaitUntilFinished(60);
                          if (recCause == FileRecorderCause.Timeout)
                          {
                              channel.FileRecorder.Stop();
                          }
  
                          // And play it back
                          if (channel.State != CallState.Idle)
                          {
                              // Replay the recorded message
                              channel.FilePlayer.Say("The following message has been recorded");
                              channel.FilePlayer.Play(recFileName);
                          }
                      }
                  }
  
                  // Make the second call on the extra channel
                  if (reply == ReturnCode.Success)
                  {
                      channel.FilePlayer.Say("Please wait while phoning contact.");
  
                      string callFrom = applicationParameters;
  
                      otherChannel = channel.ExtraChannels[0];
                      if (otherChannel.Call(destinationAddress[1], callFrom) == CallState.Answered)
                      {
                          // Play the introductory message to other call
                          otherChannel.FilePlayer.Play(recFileName);
  
                          // Connect the calls together
                          channel.FilePlayer.Say("Connecting call");
                          otherChannel.FilePlayer.Say("Connecting call");
                          channel.Connect(otherChannel);
                      }
  
                      // Wait for hang up
                      channel.WaitForIdle(Timeout.Infinite);
                  }
              }
              catch (Exception e)
              {
                  this.Trace.TraceError("Exception thrown {0}", e.Message);
                  reply = ReturnCode.ExceptionThrown;
              }
              finally
              {
                  channel.HangUp();
                  if (otherChannel != null)
                  {
                      otherChannel.HangUp();
                  }
              }
  
              this.Trace.TraceInfo("Completed");
              return (int)reply;
          }
      }
  }

• Filename:

  Samples\VB\OutboundConnect\OutboundConnect.vb

  Description:

  In this application we extract two call destination addresses from the outboundParameters argument using the String.Split() method and then ensure we have at least one extra channel available. This will allow us to make one outbound call on the primary channel (the channel argument) and one outbound call on an extra channel.

  If either of the destination addresses are PSTN numbers then the source address (caller Id) that is passed into the application via the applicationParameters argument must be set to a PSTN number that has been validated from the Caller Id page on cloud.aculab.com.

  We call the first destination address on the primary channel using the channel.Call() method and when answered, we use TTS to ask the callee to record a message that will ultimately be played to the second callee. We can record a message using the channel.FileRecorder.Start() method. This requires a filename as a parameter to identify where to store the recorded data. To play a message prompt, we use the channel.DTmfPlayer.Play() method. We wait for silence from the other end for a couple of seconds before ending the recording.

  We then call the second destination address on one of the extra channels and when answered, we play the previously recorded message to the second callee. Then we use TTS to notify both callees that they are being connected and use the Connect() method to connect both calls together bidirectionally. To wait for either caller to hangup, we use the channel.WaitForIdle() method.

  Code:

  Imports AMSClassLibrary
  Imports UASAppAPI
  
  ' An outbound application that makes calls to two destination addresses (passed in).
  ' It prompts the first call to record a message and plays this to the second call 
  ' before tromboning the two calls together. It then waits for the calls to be hung up.
  '
  ' The Caller Id (callFrom) that is to be used when calling out should be supplied in
  ' the applicationsParameters field. For outgoing SIP calls this can be empty, but for
  ' outgoing PSTN calls see the Outbound Calls documentation for your platform.
  '
  ' Requires:
  ' [outboundParameters = two destination addresses for the two outgoing calls, semicolon delimited]
  ' [applicationParameters = a validated Caller Id]
  ' [1 extra channels]
  '
  ' e.g.
  ' outboundParameters = "sip:bob@bobscompany.com;sip:brian@brianscompany.com"
  ' applicationParameters = ""
  ' or
  ' outboundParameters = "441908081876;441908678180"
  ' applicationParameters = "441908876543"
  '
  Namespace OutboundConnect
  
      ' The application class.
      ' This must have the same name as the assembly and must inherit from either 
      ' UASInboundApplication or UASOutboundApplication.
      ' It must override the Run method.
      Public Class OutboundConnect
          Inherits UASOutboundApplication
  
          ' Possible return codes
          Enum ReturnCode
              ' Success Codes:
              Success = 0
              ' ... any positive integer
  
              ' Fail Codes:
              ' -1 to -99 reserved
              ExceptionThrown = -100
              ArgumentError = -101
              NoCallerIdError = -102
              NotSufficientExtraChannels = -103
          End Enum
  
          ' This is the entry point for the application
          ' applicationParameters - Caller Id (required for outgoing PSTN, optional for outgoing SIP)
          ' outboundParameters -    2 x destinationAddresses, semicolon delimited
          Overrides Function Run(ByVal channel As UASCallChannel, _
                                 ByVal applicationParameters As String, _
                                 ByVal outboundParameters As String) _
                                 As Integer
  
              Me.Trace.TraceInfo("Start - appParms [{0}] outParms [{1}]", _
                                 applicationParameters, _
                                 outboundParameters)
              Dim reply As ReturnCode = ReturnCode.Success
  
              Dim otherChannel As UASCallChannel = Nothing
              Dim recFileName = "recordings/introMessage"
  
              Try
                  ' Typically the outboundParameters field is simply the destination address.
                  ' However, in this case we require 2 destination addresses to be specified.
                  Dim destinationAddress = outboundParameters.Split(";")
                  If destinationAddress.Length < 2 Then
                      reply = ReturnCode.ArgumentError
                      Me.Trace.TraceError("This app requires 2 destination addresses in the outboundParameters field")
                  End If
  
                  ' Check we've got an extra Channel
                  If reply = ReturnCode.Success Then
                      If channel.ExtraChannels.Length < 1 Then
                          Me.Trace.TraceError("This app requires at least 1 extra channel to be configured")
                          reply = ReturnCode.NotSufficientExtraChannels
                      End If
                  End If
  
                  ' Check we've got a Caller Id supplied if either of these calls are PSTN
                  If reply = ReturnCode.Success Then
                      If Not (destinationAddress(0).Contains("@") And destinationAddress(1).Contains("@")) Then
                          ' At least one address is a PSTN number
                          If String.IsNullOrEmpty(applicationParameters) Then
                              Me.Trace.TraceError("This app requires a validated CallerId in the applicationParameters" + _
                                                  "if any PSTN calls are to be made")
                              reply = ReturnCode.NoCallerIdError
                          End If
                      End If
                  End If
  
                  ' Make the first call on the primary channel
                  If reply = ReturnCode.Success Then
                      Dim callFrom = applicationParameters
                      Dim state = channel.Call(destinationAddress(0), callFrom)
                      If state = CallState.Answered Then
                          ' Record an introduction message
                          channel.FilePlayer.Say("Hello." + _
                                                 "Please record an introduction message for " + _
                                                 destinationAddress(1) + _
                                                 "after the tone." + _
                                                 "Press any digit to stop the recording.")
  
                          Thread.Sleep(1000)
  
                          ' Start recording, enabling barge in
                          channel.FileRecorder.Start(recFileName, True)
  
                          ' Play a tone to signal that recording has started
                          channel.DtmfPlayer.Play("0")
  
                          ' Wait for a period for recording to complete or 
                          ' the call to have been hung up
                          Dim recCause = channel.FileRecorder.WaitUntilFinished(30)
                          If recCause = FileRecorderCause.Timeout Then
                              channel.FileRecorder.Stop()
                          End If
  
                          ' And play it back
                          If channel.State <> CallState.Idle Then
                              ' Replay the recorded message
                              channel.FilePlayer.Say("The following message has been recorded")
                              channel.FilePlayer.Play(recFileName)
                          End If
                      End If
                  End If
  
                  ' Make the second call on the extra channel
                  If reply = ReturnCode.Success Then
                      channel.FilePlayer.Say("Please wait while phoning contact.")
  
                      Dim callFrom = applicationParameters
  
                      otherChannel = channel.ExtraChannels(0)
                      If otherChannel.Call(destinationAddress(1), callFrom) = CallState.Answered Then
                          ' Play the introductory message to other call
                          otherChannel.FilePlayer.Play(recFileName)
  
                          ' Connect the calls together
                          channel.FilePlayer.Say("Connecting call")
                          otherChannel.FilePlayer.Say("Connecting call")
                          channel.Connect(otherChannel)
                      End If
  
                      ' Wait for hang up
                      channel.WaitForIdle(Timeout.Infinite)
                  End If
  
              Catch ex As Exception
                  Me.Trace.TraceError("Exception thrown {0}", ex.Message)
                  reply = ReturnCode.ExceptionThrown
              Finally
                  channel.HangUp()
              End Try
  
              Me.Trace.TraceInfo("Completed")
              Return reply
  
          End Function
  
      End Class
  
  End Namespace

• Filename:

  Samples\F#\OutboundConnect\OutboundConnect.fs

  Description:

  In this application we first ensure we have at least one extra channel available. Then we extract two call destination addresses from the outboundParameters argument using the String.Split() method. This will allow us to make one outbound call on the primary channel (the channel argument) and one outbound call on an extra channel.

  If either of the destination addresses are PSTN numbers then the source address (caller Id) that is passed into the application via the applicationParameters argument must be set to a PSTN number that has been validated from the Caller Id page on cloud.aculab.com. You can set this in the Application Parameters field of the Outbound Service that runs this application. In the application this is checked using the recursive member function ContainsPSTNAddress().

  We call the first destination address on the primary channel using the channel.Call() method and when answered, we use TTS to ask the callee to record a message that will ultimately be played to the second callee. We can record a message using the channel.FileRecorder.Start() method. This requires a filename as a parameter to identify where to store the recorded data. To play a message prompt, we use the channel.DTmfPlayer.Play() method. We wait for silence from the other end for a couple of seconds before ending the recording.

  We then call the second destination address on one of the extra channels and when answered, we play the previously recorded message to the second callee. Then we use TTS to notify both callees that they are being connected and use the Connect() method to connect both calls together bidirectionally. To wait for either caller to hangup, we use the channel.WaitForIdle() method.

  Code:

  // An outbound application that makes calls to two destination addresses (passed in).
  // It prompts the first call to record a message and plays this to the second call 
  // before tromboning the two calls together. It then waits for the calls to be hung up.
  //
  // The Caller Id (callFrom) that is to be used when calling out should be supplied in
  // the applicationsParameters field. For outgoing SIP calls this can be empty, but for
  // outgoing PSTN calls see the Outbound Calls documentation for your platform.
  //
  // Requires:
  // [outboundParameters = two destination addresses for the two outgoing calls, semicolon delimited]
  // [applicationParameters = a validated Caller Id]
  // [1 extra channels]
  namespace OutboundConnect
  
      open System
      open System.Threading
      open AMSClassLibrary
      open UASAppAPI
  
      // Possible return codes
      type ReturnCode =
          // Success Codes:
          | Success = 0
          // ... any positive integer
  
          // Fail Codes:
          // -1 to -99 reserved
          | ExceptionThrown = -100
          | ArgumentError = -101
          | NoCallerIdError = -102
          | NotSufficientExtraChannels = -103
  
      // The application class.
      // This must have the same name as the assembly and must inherit from either 
      // UASInboundApplication or UASOutboundApplication.
      // It must override the Run method.
      type OutboundConnect() = 
          inherit UASOutboundApplication()
  
          // This is the entry point for the application
          override obj.Run(channel:UASCallChannel, applicationParameters:string, outboundParameters:string) : int = 
              
              obj.Trace.TraceInfo("Started")
              let mutable reply = ReturnCode.Success
  
              // Check we've got an extra Channel
              if channel.ExtraChannels.Length < 1 then
                  obj.Trace.TraceError("This app requires at least 1 extra channel to be configured")
                  int ReturnCode.NotSufficientExtraChannels
              else 
                  let otherChannel : UASCallChannel = channel.ExtraChannels.[0]
                  let recFileName = "recordings/introMessage"
  
                  try
                      try
                          // Typically the outboundParameters field is simply the destination address.
                          // However, in this case we require 2 destination addresses to be specified.
                          let destinationAddresses = outboundParameters.Split(';')
                          if destinationAddresses.Length < 2 then
                              reply <- ReturnCode.ArgumentError
                              obj.Trace.TraceError("This app requires 2 destination addresses in the outboundParameters field")
  
                          // Check we've got a Caller Id supplied if either of these calls are PSTN
                          if reply = ReturnCode.Success then
                              if obj.ContainsPSTNAddress(destinationAddresses) then
                                  // At least one address is a PSTN number
                                  if String.IsNullOrEmpty(applicationParameters) then
                                      obj.Trace.TraceError("This app requires a validated CallerId in the applicationParameters" +
                                                            "if any PSTN calls are to be made")
                                      reply <- ReturnCode.NoCallerIdError
                  
                          // Make the first call on the primary channel
                          if reply = ReturnCode.Success then
                              let callFrom = applicationParameters
  
                              let state = channel.Call(destinationAddresses.[0], callFrom)
                              if state = CallState.Answered then
                                  // Record an introduction message
                                  channel.FilePlayer.Say("Hello." +
                                                         "Please record an introduction message for " +
                                                         destinationAddresses.[1] +
                                                         "after the tone." +
                                                         "Press any digit to stop the recording.") |> ignore
  
                                  Thread.Sleep(1000)
  
                                  // Start recording, enabling barge in
                                  channel.FileRecorder.Start(recFileName, true) |> ignore
  
                                  // Play a tone to signal that recording has started
                                  channel.DtmfPlayer.Play("0") |> ignore
  
                                  // Wait for a period for recording to complete or 
                                  // the call to have been hung up
                                  let recCause = channel.FileRecorder.WaitUntilFinished(30)
                                  if recCause = FileRecorderCause.Timeout then
                                      channel.FileRecorder.Stop() |> ignore
  
                                  // And play it back
                                  if channel.State <> CallState.Idle then
                                      // Replay the recorded message
                                      channel.FilePlayer.Say("The following message has been recorded") |> ignore
                                      channel.FilePlayer.Play(recFileName) |> ignore
  
                          // Make the second call on the extra channel
                          if reply = ReturnCode.Success then
                              channel.FilePlayer.Say("Please wait while phoning contact.") |> ignore
  
                              let callFrom = applicationParameters
  
                              if otherChannel.Call(destinationAddresses.[1], callFrom) = CallState.Answered then
  
                                  // Play the introductory message to other call
                                  otherChannel.FilePlayer.Play(recFileName) |> ignore
  
                                  // Connect the calls together
                                  channel.FilePlayer.Say("Connecting call") |> ignore
                                  otherChannel.FilePlayer.Say("Connecting call") |> ignore
                                  channel.Connect(otherChannel) |> ignore
  
                              // Wait for hang up
                              channel.WaitForIdle(Timeout.Infinite) |> ignore
                      with
                          | _ as e->
                              obj.Trace.TraceError("Exception thrown {0}", e.Message)
                              reply <- ReturnCode.ExceptionThrown
                  finally
                      channel.HangUp() |> ignore
                      if otherChannel <> null then
                          otherChannel.HangUp() |> ignore
                  
                  obj.Trace.TraceInfo("Completed")
                  int reply
  
          // Check whether an array of addresses contains a PSTN address
          member obj.ContainsPSTNAddress (addresses : string[]) =
              let rec IsPSTNAddress(addresses : string[], index : int) : bool =
                  if index < addresses.Length then
                      false 
                  elif addresses.[index].Contains("@") then
                      true
                  else
                      IsPSTNAddress(addresses, index + 1)
              IsPSTNAddress(addresses, 0)
  

UAS API - Pin Input Sample Application

• Python
• C#
• VB
• F#

• Filename:

  samples/pin_input.py

  Description:

  An inbound application that prompts the caller to enter a 4 digit pin. After ringing and answering an inbound call, the application uses TTS to ask for a four digit PIN using channel.FilePlayer.say(). The channel.DTMFDectector.get_digits() function is used to collect the DTMF digits. The count argument indicates the number of digits to collect, and the seconds_predigits_timeout argument specifies how long to wait for the first key press before timing out.

  The DTMF detector return cause is checked by using the channel.DTMFDetector.cause() function. In this case, if the correct number of digits were entered, TTS is use to play back the digits that were collected; otherwise an error message is spoken.

  Code:

  """
      An inbound application that prompts the caller to enter a 4 digit pin. 
      It waits at most 30 seconds for the caller to begin entering digits, then replays 
      the digits to the caller before hanging up.
  """
  
  from prosody.uas import Hangup, Error
  
  __uas_identify__ = "application"
  __uas_version__  = "1.0b2"
  
  def main(channel, application_instance_id, file_man, my_log, application_parameters):
      return_code = 0
      try:
          if channel.state() == channel.State.CALL_INCOMING:
              channel.ring()   # this can raise a Hangup exception
              channel.answer() # this can raise a Hangup exception
          else:
              raise Hangup('No inbound call')
  
          channel.FilePlayer.say("Please enter a four digit pin.", barge_in = True)
  
          # wait at most 30 seconds for the caller to begin entering digits
          digits = channel.DTMFDetector.get_digits(count=4, seconds_predigits_timeout = 30)
  
          if channel.DTMFDetector.cause() == channel.DTMFDetector.Cause.COUNT:
              channel.FilePlayer.say("The digits you entered are, {0}".format(", ".join(digits)))
          else:
              channel.FilePlayer.say ("No digits received. Hanging up.")
              return_code = -103
  
      except Hangup as exc:
          my_log.info("Got Hangup: {0}".format(exc))
          return_code = -100
  
      except Error as exc:
          my_log.error("Got Error: {0}".format(exc))
          return_code = -101
  
      except Exception as exc:
          my_log.exception("Got unexpected exception: {0}".format(exc))
          return_code = -102
  
      finally:
          if channel.state() != channel.State.IDLE:
              channel.hang_up()
      return return_code
  

• Filename:

  Samples\C#\PinInput\PinInput.cs

  Description:

  Once the call is answered with channel.Answer(), we use TTS to prompt for a four digit PIN code. The channel.DtmfDetector can obtain the digits entered by the caller for us, using the GetDigits() method. The specific overload used requires the expected number of digits, an output string in which the resultant digits are stored and a timeout value of 30 seconds. The method returns a cause value indicating why the method returned. The DtmfDetectorCause.Count cause signifies that the expected count of digits were detected.

  The code then responds to the caller with the digits entered. Note that the text has some formatting to ensure that TTS reads it in a natural manner. The call is then disconnected using the channel.HangUp() method.

  Code:

  using System;
  using System.Threading;
  using AMSClassLibrary;
  using UASAppAPI;
  
  // An inbound application that answers a call, prompts for the caller to 
  // enter a 4 digit pin code. It waits for 30 seconds for 4 digits to be entered 
  // and then replays them to the caller before hanging up.
  namespace PinInput
  {
      // The application class.
      // This must have the same name as the assembly and must inherit from either 
      // UASInboundApplication or UASOutboundApplication.
      // It must override the Run method.
      public class PinInput : UASInboundApplication
      {
          // Possible return codes
          enum ReturnCode
          {
              // Success Codes:
              Success = 0,
              // ... any positive integer
  
              // Fail Codes:
              // -1 to -99 reserved
              ExceptionThrown = -100
          }
  
          // This is the entry point for the application
          public override int Run(UASCallChannel channel,
                                  string applicationParameters)
          {
              this.Trace.TraceInfo("Started");
              ReturnCode reply = ReturnCode.Success;
  
              try
              {
                  // Answer the call
                  CallState state = channel.Answer();
                  if (state == CallState.Answered)
                  {
                      // Prompt to enter a pin, allowing bargein
                      channel.FilePlayer.Say("Please enter a four digit pin code.", true);
  
                      // Wait for 30 seconds for four digits
                      string digits;
                      DtmfDetectorCause cause = channel.DtmfDetector.GetDigits(4, out digits, 30);
                      if (cause == DtmfDetectorCause.Count)
                      {
                          channel.FilePlayer.Say(
                      		"The pin code you entered was <say-as interpret-as='vxml:digits'>{0}</say-as>",
                      		digits);
                      }
  
                      channel.FilePlayer.Say("Goodbye.");
                  }
              }
              catch (Exception e)
              {
                  this.Trace.TraceError("Exception thrown {0}", e.Message);
                  reply = ReturnCode.ExceptionThrown;
              }
              finally
              {
                  channel.HangUp();
              }
  
              this.Trace.TraceInfo("Completed");
              return (int)reply;
          }
      }
  }

• Filename:

  Samples\VB\PinInput\PinInput.vb

  Description:

  Once the call is answered with channel.Answer(), we use TTS to prompt for a four digit PIN code. The channel.DtmfDetector can obtain the digits entered by the caller for us, using the GetDigits() method. The specific overload used requires the expected number of digits, an output string in which the resultant digits are stored and a timeout value of 30 seconds. The method returns a cause value indicating why the method returned. The DtmfDetectorCause.Count cause signifies that the expected count of digits were detected.

  The code then responds to the caller with the digits entered. Note that the text has some formatting to ensure that TTS reads it in a natural manner. The call is then disconnected using the channel.HangUp() method.

  Code:

  Imports AMSClassLibrary
  Imports UASAppAPI
  
  ' An inbound application that answers a call, prompts for the caller to 
  ' enter a 4 digit pin code. It waits for 30 seconds for 4 digits to be entered 
  ' and then replays them to the caller before hanging up.
  Namespace PinInput
  
      ' The application class.
      ' This must have the same name as the assembly and must inherit from either 
      ' UASInboundApplication or UASOutboundApplication.
      ' It must override the Run method.
      Public Class PinInput
          Inherits UASInboundApplication
  
          ' Possible return codes
          Enum ReturnCode
              ' Success Codes:
              Success = 0
              ' ... any positive integer
  
              ' Fail Codes:
              ' -1 to -99 reserved
              ExceptionThrown = -100
          End Enum
  
          ' This is the entry point for the application
          Overrides Function Run(ByVal channel As UASCallChannel, _
                                 ByVal applicationParameters As String) _
                                 As Integer
  
              Me.Trace.TraceInfo("Started")
              Dim reply As ReturnCode = ReturnCode.Success
  
              Try
                  ' Answer the call
                  Dim state As CallState
                  state = channel.Answer()
  
                  If state = CallState.Answered Then
  
                      ' Prompt to enter a pin
                      channel.FilePlayer.Say("Please enter a four digit pin code.")
  
                      ' Wait for 30 seconds for four digits
                      Dim digits As String = ""
                      Dim cause = channel.DtmfDetector.GetDigits(4, digits, 30)
                      If cause = DtmfDetectorCause.Count Then
                          channel.FilePlayer.Say("The pin code you entered was {0}, {1}, {2}, {3}", _
                              digits(0), _
                              digits(1), _
                              digits(2), _
                              digits(3))
                      End If
  
                      channel.FilePlayer.Say("Goodbye.")
                  End If
              Catch ex As Exception
                  Me.Trace.TraceError("Exception thrown {0}", ex.Message)
                  reply = ReturnCode.ExceptionThrown
              Finally
                  channel.HangUp()
              End Try
  
              Me.Trace.TraceInfo("Completed")
              Return reply
  
          End Function
  
      End Class
  
  End Namespace

• Filename:

  Samples\F#\PinInput\PinInput.fs

  Description:

  Once the call is answered with channel.Answer(), we use TTS to prompt for a four digit PIN code. The channel.DtmfDetector obtain the digits entered by the caller for us, using the GetDigits() method. The specific overload used requires the expected number of digits, an output string in which the resultant digits are stored and a timeout value of 30 seconds. The method returns a cause value indicating why the method returned. The DtmfDetectorCause.Count cause signifies that the expected count of digits were detected.

  The code then responds to the caller with the digits entered. Note that the text has some formatting to ensure that TTS reads it in a natural manner. The call is then disconnected using the channel.HangUp() method.

  Code:

  // An inbound application that answers a call, prompts for the caller to 
  // enter a 4 digit pin code. It waits for 30 seconds for 4 digits to be entered 
  // and then replays them to the caller before hanging up.
  namespace PinInput
  
      open System
      open System.Threading
      open AMSClassLibrary
      open UASAppAPI
  
      // Possible return codes
      type ReturnCode =
          // Success Codes:
          | Success = 0
          // ... any positive integer
  
          // Fail Codes:
          // -1 to -99 reserved
          | ExceptionThrown = -100
  
      // The application class.
      // This must have the same name as the assembly and must inherit from either 
      // UASInboundApplication or UASOutboundApplication.
      // It must override the Run method.
      type PinInput() = 
          inherit UASInboundApplication()
  
          // This is the entry point for the application
          override obj.Run(channel:UASCallChannel, applicationParameters:string) : int = 
              
              obj.Trace.TraceInfo("Started")
              let mutable reply = ReturnCode.Success
  
              try
                  // Answer the call
                  if channel.Answer() = CallState.Answered then
  
                      // Prompt to enter a pin
                      channel.FilePlayer.Say("Please enter a four digit pin code.") |> ignore
  
                      // Wait for 30 seconds for four digits
                      let mutable digits = ""
                      let cause = channel.DtmfDetector.GetDigits(4, &digits, 30)
                      match cause with
                          | DtmfDetectorCause.Count -> 
                              match digits.Length with
                                  | 0 -> 
                                      channel.FilePlayer.Say("Pin empty.") |> ignore
                                  | _ ->
                                      channel.FilePlayer.Say("The pin code you entered was {0}, {1}, {2}, {3}", digits.Chars(0), digits.Chars(1), digits.Chars(2), digits.Chars(3)) |> ignore
                          | _ -> 
                              channel.FilePlayer.Say("Pin Not entered.") |> ignore
  
                      channel.FilePlayer.Say("Goodbye.") |> ignore
              with 
                  | _ as e -> 
                      obj.Trace.TraceError("Exception thrown {0}", e.Message)
                      reply <- ReturnCode.ExceptionThrown
                  
              obj.Trace.TraceInfo("Completed")
              (int)reply
              

UAS API - Transfer Menu Sample Application

• Python
• C#
• VB

• Filename:

  samples/transfer_menu.py

  Description:

  An inbound application that prompts the user to select a target to be transfered to. The target names (to be read out using TTS) and addresses (to be transfered to using the channel API) are given in application_parameters which is configured on the Inbound Services page. The target addresses must be other inbound services that have been registered on the Inbound Services page.

  This example requires that application_parameters is a semi-colon delimited list in the format: <target name>,<target address>;<target name>,<target address> for example: join a conference,sip:AddToConfService@sip-0-2-0.aculab.com;listen to music,sip:InBoundMusic@sip-0-2-0.aculab.com This application requires one extra channel.

  The application rings and answers the call, it then tries to get the extra channel. It then splits up the information in application_arguments to generate the transfer menu list. The application then uses TTS to prompt the caller for a menu choice. Finally, it uses the channel.transfer_to_inbound_service() function to transfer the caller to another inbound service. This function requires a reference to an extra channel.

  The get_menu_selection() function has a loop which says each item in the transfer menu list, and then waits for a valid DTMF digit (one which corresponds to a transfer option). The transfer name and destination are returned by the function.

  Code:

  __uas_identify__ = "application"
  __uas_version__ = "1.0b1"
  
  from prosody.uas import Hangup, Error, PlayableMedia
  from prosody.uas.highlevel import HighLevelCallChannel, HighLevelGrammar, HighLevelDigitInputOptions
  
  """
      An inbound application that prompts the user to select a target to be transferred to. 
      
      The target names and addresses - or phone numbers - are provided in application_parameters.
      These are set, during service registration, on the inbound service registration page at cloud.aculab.com.    
  
      The application_parameters must be a delimited string in the format: <name>, <address>; <name>, <address>
      
      For example:
      "Fred,sip:fred@place.com;Jack,sip:jack@place.com"
  
      The target names are used to create an automatic speech recognition (ASR) grammar.
      ASR is used to get the caller's choice and the call is then connected to the target address.
      
      A digit is associated with each name, and this can be entered on the telephone keypad instead of speaking.
  
      At application start, the target names are read out along with the associated digit.
  
      This application requires 1 extra channel.
      
      Actions:
          - wait for an inbound call
          - generate the transfer options menu
          - speak the options using TTS
          - listen for the caller's selection using ASR and DTMF
          - transfer the call
  
  """
  
  def transfer_menu(application_parameters, my_log):
      # Split the application_parameters up into transfer options
      # (split with semicolon), and then again with commas. Return the 
      # data as a dictionary
  
      try:
          return dict(tuple(a.split(',')) for a in application_parameters.split(';'))
      except Exceptionas exc:
           my_log.error("The application parameters could not be parsed correctly: {0}".format(exc))
      return {}
  
  
  def get_menu_selection(channel, transfer_list, my_log):
  
      channel.DTMFDetector.clear_digits()
      my_log.info("transfer_list: {0}".format(transfer_list))
      
      # create a speech recognition grammar of the IVR options
      my_grammar = HighLevelGrammar()
      my_grammar.create_from_alternatives(*transfer_list.keys())
      
      valid_digits = range(len(transfer_list))
      my_digit_options = HighLevelDigitInputOptions(valid_digits=''.join(map(str, valid_digits)))
  
      prompt_text = 'Please say the name of the person you want to call. Or press '
      for digit in valid_digits:
          # associate digits with the names
          prompt_text = prompt_text + "{0} for {1}, ".format(digit, transfer_list.keys()[digit])
  
      prompt = PlayableMedia(text_to_say=prompt_text, channel=channel)
      response = channel.capture_input(prompt, speech_recognition_grammar=my_grammar, 
                                    digit_input_options=my_digit_options)
      # if response is None, no valid input was detected
      if response is not None:
          # check whether we got speech or digits
          if response.type == response.Type.SPEECH:
              # return the name
              return response.input
          else:
              # return the name associated with the digit
              return transfer_list.keys()[int(response.input)]
      return None
  
  
  def main(channel, application_instance_id, file_man, my_log, application_parameters):
      my_log.info("Transfer menu started")
      return_code = 0
      try:
          channel.ring(1)
          channel.answer()
          my_log.info("Call answered")
  
          # in this application, we will using the high level API wrapper
          # for the channel object
          high_level_channel = HighLevelCallChannel(channel, my_log)        
          try:
              # an extra channel is required, the number of extra channels
              # available is set on the service page
              out_channel = channel.ExtraChannel[0]
          except:
              raise Error("You need to register an extra channel for this application.")
  
          # Convert the application_parameters into a transfer menu list for later use
          transfer_list = transfer_menu(application_parameters)
          if not transfer_list:
              raise Error("Invalid transfer menu")
          
          # Prompt for digit
          channel.FilePlayer.say("Hello. ")
          target = get_menu_selection(high_level_channel, transfer_list, my_log)
  
          if not target:
              channel.FilePlayer.say("There is nobody to call.")
          else:
              # we will use the high level channel to place an outbound call and connect
              # the inbound and outbound calls together. If the target is a PSTN call
              # you will have to supply a call_from as well - please see the online documentation
              # on placing outbound PSTN calls.
              print("Calling {0}".format(target))
              if high_level_channel.call_and_connect(out_channel, call_to=transfer_list[target]) is False:
                  channel.FilePlayer.say("I wasn't able to transfer you. Please try again later.")
                  channel.hang_up()
              
          channel.wait_for_idle()
  
      except Hangup as exc:
          my_log.info("Got Hangup")
          return_code = 100
  
      except Error as exc:
          my_log.error("Got Error: {0}".format(exc))
          return_code = -101
  
      except Exception as exc:
          my_log.exception("Got unexpected exception: {0}".format(exc))
          return_code = -102
  
      finally:
          if channel.state() != channel.State.IDLE:
              channel.hang_up()
      return return_code
  

• Filename:

  Samples\C#\TransferMenu\TransferMenu.cs

  Description:

  This application first checks to ensure that the Inbound Service that invoked this application has allocated sufficient extra channels, by inspecting the channel.ExtraChannels array. Extra channels are required to make outbound calls in an inbound application and can be configured in the Inbound Service configuration. Once the check has been made, the application splits the applicationParameters into an array for further use.

  The call is answered, a small TTS message is sent to the user and then the GetMenuSelection() method is called. This method will prompt the user for a DTMF tone after giving a list of the transfer options. We use the channel.DtmfDetector.GetDigits() method to grab a single keypad press and then make sure the returned item is in our list of transfer options. This loop will continue until either a valid keypress has been detected, or the user hangs up.

  To transfer the call, we use the channel.TransferToInboundService() method. We specify the target address and the extra channel to use for the transfer. The function returns a boolean value indicating if the transfer attempt was successful. This transfer method uses the retrievable transfer mechanism and therefore we must maintain the state of the original channel to allow the transferred call to continue. So we wait for the transferred call to be hung up before terminating.

  Code:

  using System;
  using System.Threading;
  using System.Collections.Generic;
  using AMSClassLibrary;
  using UASAppAPI;
  
  // An inbound application that prompts the user to select a target inbound service 
  // to be transferred to. A prompt (to be read out) and service name (to be transferred to) 
  // for each possible target need to be listed in the applicationParameters when
  // this service is registered.
  //
  // Note: this sample will only run on platforms that support Transfer.
  //
  // Requires:
  // [applicationParameters = semicolon delimited list of <action>,<service name<
  //      e.g. "join a conference,AddToConference;
  //            listen to media file,InboundPlayWav"]
  // [1 extra channel]
  namespace TransferMenu
  {
      // The application class.join a 
      // This must have the same name as the assembly and must inherit from either 
      // UASInboundApplication or UASOutboundApplication.
      // It must override the Run method.
      public class TransferMenu : UASInboundApplication
      {
          // Possible return codes
          enum ReturnCode
          {
              // Success Codes:
              Success = 0,
              // ... any positive integer
  
              // Fail Codes:
              // -1 to -99 reserved
              ExceptionThrown = -100,
              NotSufficientExtraChannels = -101,
              NotSufficientDestinations = -102
          }
  
          // A class to represent each of the menu options
          class TransferTarget
          {
              public TransferTarget(string entry, int key)
              {
                  string[] details = entry.Split(',');
                  if (details.Length != 2)
                  {
                      throw new ArgumentException("Invalid destination details", "applicationParameters");
                  }
                  Prompt = details[0].Trim();
                  ServiceName = details[1].Trim();
                  Key = key;
              }
              public string Prompt;
              public string ServiceName;
              public int Key;
          }
  
          // This is the entry point for the application
          public override int Run(UASCallChannel channel,
                                  string applicationParameters)
          {
              this.Trace.TraceInfo("Started");
              ReturnCode reply = ReturnCode.Success;
              bool primaryCallHungUp = false;
  
              // Check we've got an extra Channel
              if (channel.ExtraChannels.Length < 1)
              {
                  this.Trace.TraceWarning("Needs 1 extra channel to be configured");
                  return (int)ReturnCode.NotSufficientExtraChannels;
              }
              UASCallChannel targetChannel = channel.ExtraChannels[0];
  
              try
              {
                  // Decipher the applicationParameters
                  string[] entries = applicationParameters.Split(';');
                  if (entries.Length < 1)
                  {
                      this.Trace.TraceWarning("Needs at least 1 transfer target to be configured");
                      return (int)ReturnCode.NotSufficientDestinations;
                  }
                  List<TransferTarget> targets = new List<TransferTarget>(entries.Length);
                  int key = 0;
                  foreach (string entry in entries)
                  {
                      targets.Add(new TransferTarget(entry, key++));
                  }
  
                  // The selected target
                  TransferTarget target = null;
  
                  // Answer the call
                  CallState state = channel.Answer();
                  if (state != CallState.Answered)
                  {
                      primaryCallHungUp = true;
                  }
  
                  if (!primaryCallHungUp)
                  {
                      this.Trace.TraceInfo("Call answered");
  
                      // Prompt for a digit
                      channel.FilePlayer.Say("Hello.");
                      target = getMenuSelection(channel, targets);
                      if (target == null)
                      {
                          primaryCallHungUp = true;
                      }
                  }
  
                  if (!primaryCallHungUp)
                  {
                      // Transfer to that target
                      channel.FilePlayer.Say("Transferring to {0}", target.Prompt);
                      state = channel.TransferToInboundService(
                                                  target.ServiceName,
                                                  targetChannel);
  
                      if (state != CallState.Transferred)
                      {
                          channel.FilePlayer.Say("I wasn't able to transfer you.");
                          channel.FilePlayer.Say("Please try again later.");
                      }
                      else
                      {
                          // Wait for transferree or far end to hangup 
                          channel.WaitForTransferredCallRetrieved(Timeout.Infinite);
                      }
                  }
              }
              catch (Exception e)
              {
                  this.Trace.TraceError("Exception thrown {0}", e.Message);
                  reply = ReturnCode.ExceptionThrown;
              }
              finally
              {
                  channel.HangUp();
              }
  
              this.Trace.TraceInfo("Completed");
              return (int)reply;
          }
  
          TransferTarget getMenuSelection(UASCallChannel channel, List<TransferTarget> targets)
          {
              // Prepare to receive digits
              channel.DtmfDetector.ClearDigits();
  
              // Get the target selected
              do
              {
                  // Play the transfer options to the caller with bargein
                  foreach (TransferTarget target in targets)
                  {
                      string msg = string.Format("Press {0} to {1}", target.Key, target.Prompt);
                      FilePlayerCause cause = channel.FilePlayer.Say(msg, true);
                      if (cause == FilePlayerCause.HangUp)
                      {
                          return null;
                      }
                      if (cause == FilePlayerCause.BargeIn)
                      {
                          break;
                      }
                  }
  
                  string digits;
                  channel.DtmfDetector.GetDigits(1, out digits, 10);
                  if (channel.DtmfDetector.Cause == DtmfDetectorCause.Count)
                  {
                      // Get the transfer target
                      int keyPressed = Convert.ToInt32(digits);
                      this.Trace.TraceInfo("Got keypress {0}", keyPressed);
                      if (keyPressed < targets.Count)
                      {
                          return targets[keyPressed];
                      }
                      channel.FilePlayer.Say("Selection not valid.");
                  }
              } while (channel.DtmfDetector.Cause != DtmfDetectorCause.HangUp);
  
              // returning null on hangup
              return null;
          }
      }
  }

• Filename:

  Samples\VB\TransferMenu\TransferMenu.vb

  Description:

  This application first checks to ensure that the Inbound Service that invoked this application has allocated sufficient extra channels, by inspecting the channel.ExtraChannels array. Extra channels are required to make outbound calls in an inbound application and can be configured in the Inbound Service configuration. Once the check has been made, the application splits the applicationParameters into an array for further use.

  The call is answered, a small TTS message is sent to the user and then the GetMenuSelection() method is called. This method will prompt the user for a DTMF tone after giving a list of the transfer options. We use the channel.DtmfDetector.GetDigits() method to grab a single keypad press and then make sure the returned item is in our list of transfer options. This loop will continue until either a valid keypress has been detected, or the user hangs up.

  To transfer the call, we use the channel.TransferToInboundService() method. We specify the target address and the extra channel to use for the transfer. The function returns a boolean value indicating if the transfer attempt was successful. This transfer method uses the retrievable transfer mechanism and therefore we must maintain the state of the original channel to allow the transferred call to continue. So we wait for the transferred call to be hung up before terminating.

  Code:

  Imports System.Collections.Generic
  Imports AMSClassLibrary
  Imports UASAppAPI
  
  ' An inbound application that prompts the user to select a target inbound service 
  ' to be transferred to. A prompt (to be read out) and service name (to be transferred to) 
  ' for each possible target need to be listed in the applicationParameters when
  ' this service is registered.
  '
  ' Note: this sample will only run on platforms that support Transfer.
  '
  ' Requires:
  ' [applicationParameters = semicolon delimited list of <action>,<service name>
  '      e.g. "join a conference,AddToConference;listen to media file,InboundPlayWav"]
  ' [1 extra channel]
  Namespace TransferMenu
  
      Public Class TransferMenu
          Inherits UASInboundApplication
  
          ' Possible return codes
          Enum ReturnCode
              ' Success Codes:
              Success = 0
              ' ... any positive integer
  
              ' Fail Codes:
              ' -1 to -99 reserved
              ExceptionThrown = -100
              NotSufficientExtraChannels = -101
              NotSufficientDestinations = -102
          End Enum
  
          ' A class to represent each of the menu options
          Class TransferTarget
              Public Sub New(ByVal entry As String, _
                             ByVal keyin As Integer)
                  Dim details = entry.Split(",")
                  If details.Length <> 2 Then
                      Throw New ArgumentException("Invalid destination details", "applicationParameters")
                  End If
                  Prompt = details(0).Trim()
                  ServiceName = details(1).Trim()
                  Key = keyin
              End Sub
  
              Public Prompt As String
              Public ServiceName As String
              Public Key As Integer
          End Class
  
          ' This is the entry point for the application
          Overrides Function Run(ByVal channel As UASCallChannel, _
                                 ByVal applicationParameters As String) _
                                 As Integer
  
              Me.Trace.TraceInfo("Started")
  
              Dim reply = ReturnCode.Success
              Dim primaryCallHungUp = False
  
              ' Check we've got an extra Channel
              If channel.ExtraChannels.Length < 1 Then
                  Me.Trace.TraceWarning("Needs 1 extra channel to be configured")
                  Return ReturnCode.NotSufficientExtraChannels
              End If
  
              Dim targetChannel = channel.ExtraChannels(0)
  
              Try
                  ' Decipher the applicationParameters
                  Dim entries = applicationParameters.Split(";")
                  If entries.Length < 1 Then
                      Me.Trace.TraceWarning("Needs at least 1 transfer target to be configured")
                      Return ReturnCode.NotSufficientDestinations
                  End If
  
                  Dim targets = New List(Of TransferTarget)
                  Dim key = 0
                  For Each entry In entries
                      targets.Add(New TransferTarget(entry, key))
                      key += 1
                  Next
  
                  ' The selected target
                  Dim target As TransferTarget = Nothing
  
                  ' Answer the call
                  Dim state = channel.Answer()
                  If state <> CallState.Answered Then
                      primaryCallHungUp = True
                  End If
  
                  If Not primaryCallHungUp Then
                      Me.Trace.TraceInfo("Call answered")
  
                      ' Prompt for a digit
                      channel.FilePlayer.Say("Hello.")
                      target = getMenuSelection(channel, targets)
                      If target Is Nothing Then
                          primaryCallHungUp = True
                      End If
                  End If
  
                  If Not primaryCallHungUp Then
                      ' Transfer to that target
                      channel.FilePlayer.Say("Transferring to {0}", target.Prompt)
                      state = channel.TransferToInboundService(target.ServiceName, targetChannel)
  
                      If state <> CallState.Transferred Then
                          channel.FilePlayer.Say("I wasn't able to transfer you.")
                          channel.FilePlayer.Say("Please try again later.")
                      Else
                          ' Wait for transferree or far end to hangup 
                          channel.WaitForTransferredCallRetrieved(Timeout.Infinite)
                      End If
                  End If
              Catch e As Exception
                  Me.Trace.TraceError("Exception thrown {0}", e.Message)
                  reply = ReturnCode.ExceptionThrown
              Finally
                  channel.HangUp()
              End Try
  
              Me.Trace.TraceInfo("Completed")
              Return reply
  
          End Function
  
          Function getMenuSelection(ByVal channel As UASCallChannel, ByVal targets As List(Of TransferTarget)) As TransferTarget
              ' Prepare to receive digits
              channel.DtmfDetector.ClearDigits()
  
              ' Get the target selected
              Do
                  ' Play the transfer options to the caller with bargein
                  For Each target In targets
                      Dim msg = String.Format("Press {0} to {1}", target.Key, target.Prompt)
                      Dim cause = channel.FilePlayer.Say(msg, True)
                      If cause = FilePlayerCause.HangUp Then
                          Return Nothing
                      End If
                      If cause = FilePlayerCause.BargeIn Then
                          Exit Do
                      End If
                  Next
  
                  Dim digits As String = ""
                  channel.DtmfDetector.GetDigits(1, digits, 10)
                  If channel.DtmfDetector.Cause = DtmfDetectorCause.Count Then
                      ' Get the transfer target
                      Dim keyPressed = Convert.ToInt32(digits)
                      Me.Trace.TraceInfo("Got keypress {0}", keyPressed)
                      If keyPressed < targets.Count Then
                          Return targets(keyPressed)
                      End If
                      channel.FilePlayer.Say("Invalid selection.")
                  End If
              Loop While channel.DtmfDetector.Cause <> DtmfDetectorCause.HangUp
  
              ' returning null on hangup
              Return Nothing
          End Function
  
      End Class
  
  End Namespace

UAS API - Add To Conference Sample Application

• Python
• C#
• VB

• Filename:

  samples/add_to_conference.py

  Description:

  This sample application will transfer the caller to a conference room. Using channel.FilePlayer.say(), the application askes the caller to enter a four digit PIN, representing a conference room ID, channel.DTMFDetector.get_digits() is used to retrieve the digits. If the right number of digits has been collected, the application will call channel.transfer_to_conference() to transfer the caller to the conference room. If the conference room does not already exist, it will be created. There will be silence on the line until someone else enters.

  Code:

  """
      An inbound application that prompts the user to enter a 4-digit pin that represents a 
      conference room, to which they are then transferred. Please read the documentation about
      conference rooms.
  
      The application uses TTS to communicate with the caller.
  
      This application requires 1 extra channel.
  
      Actions:
          - wait for anbound call
          - wait for four DTMF digits
          - create a tone player
          - transfer the call to the conference room
          - wait for the caller to hang up
  
  """
  
  from prosody.uas import Hangup, Error, ToneManager
  
  __uas_identify__ = "application"
  __uas_version__  = "1.0b1"
  
  def main(channel, application_instance_id, file_man, my_log, application_parameters):
  
      return_code = 0
  
      try:
          if channel.state() == channel.State.CALL_INCOMING:
              channel.ring()   # this can raise a Hangup exception
              channel.answer() # this can raise a Hangup exception
          else:
              raise Hangup('No inbound call')
  
          # get the extra channel
          try:
              out_channel = channel.ExtraChannel[0]
          except:
              raise Error("You need to register an extra channel for this application")
  
          channel.FilePlayer.say("Please enter a four digit conference i d.", barge_in = True)
  
          digits = channel.DTMFDetector.get_digits(count=4, seconds_predigits_timeout = 10)
  
          if channel.DTMFDetector.cause() == channel.DTMFDetector.Cause.COUNT:
              channel.FilePlayer.say("Adding you to conference {0}".format(", ".join(digits)))
  
              # because this is a transfer, we need to create the tone player
              tone_manager = ToneManager(my_log)
              channel.create_tone_player(tone_manager)
                                      
              if channel.transfer_to_conference_room(out_channel, digits) is False:
                  my_log.error("Transfer to conference. Hanging up")
                  channel.FilePlayer.say ("Sorry, I could not connect you to your conference. Good bye")
                  return_code = -104
              else:
                  my_log.info ("Transfer to conference {0} succeeded. Waiting for idle".format (digits))
                  channel.wait_for_idle(seconds_timeout=None)
          else:
              channel.FilePlayer.say ("I did not receive four digits. Hanging up.")
              return_code = -103
              
      except Hangup as exc:
          my_log.info("Got Hangup")
          return_code = -100
  
      except Error as exc:
          my_log.error("Got Error {0}".format(exc))
          return_code = -102
  
      except Exception as exc:
          my_log.exception("Got unexpected exception {0}".format(exc))
          return_code = -101
  
      finally:
          if channel.state() != channel.State.IDLE:
              channel.hang_up()
      return return_code
  

• Filename:

  Samples\C#\AddToConference\AddToConference.cs

  Description:

  We ask for a four digit PIN code, representing the conference ID number, receive it using DTMF detection and then repeat the number back to the caller for confirmation. We can then use the channel.TransferToConferenceRoom() method, that will manage the transfer for us, passing it one of the extra channels to use for the transfer.

  We construct a ConferencePartyMediaSettings object to allow us to disable DTMF suppression which is enabled by default. The conference is configured to produce silence on the line until someone else enters the conference room.

  Code:

  using System;
  using System.Threading;
  
  using AMSClassLibrary;
  using UASAppAPI;
  
  // An inbound application that prompts the user to enter a 4-digit pin that represents 
  // the id of a conference to which they are then transferred.
  //
  // Note: this sample will only run on platforms that support Transfer.
  //
  // Requires:
  // [1 extra channel]
  namespace AddToConference
  {
      // The application class.
      // This must have the same name as the assembly and must inherit from either 
      // UASInboundApplication or UASOutboundApplication.
      // It must override the Run method.
      public class AddToConference : UASInboundApplication
      {
          // Possible return codes
          enum ReturnCode
          {
              // Success Codes:
              Success = 0,
              // ... any positive integer
  
              // Fail Codes:
              // -1 to -99 reserved
              ExceptionThrown = -100,
              NotSufficientExtraChannels = -101
          }
  
          // This is the entry point for the application
          public override int Run(UASCallChannel channel,
                                  string applicationParameters)
          {
              this.Trace.TraceInfo("Started");
              ReturnCode reply = ReturnCode.Success;
              string conferenceId;
  
              // Check we've got an extra Channel
              if (channel.ExtraChannels.Length < 1)
              {
                  this.Trace.TraceWarning("Needs 1 extra channel to be configured");
                  return (int)ReturnCode.NotSufficientExtraChannels;
              }
              UASCallChannel targetChannel = channel.ExtraChannels[0];
  
              try
              {
                  // Answer the call
                  CallState state = channel.Answer();
                  if (state == CallState.Answered)
                  {
                      this.Trace.TraceInfo("Call answered");
  
                      // Prompt for a conference id, enabling bargein
                      channel.FilePlayer.Say("Please Enter a four digit conference i d.", true);
  
                      string digits;
                      DtmfDetectorCause cause = channel.DtmfDetector.GetDigits(4, out digits, 30);
                      if (cause == DtmfDetectorCause.Count)
                      {
                          conferenceId = digits;
  
                          // Inform the caller what is happening
                          channel.FilePlayer.Say(
                              "Adding you to conference <say-as interpret-as='vxml:digits'>{0}</say-as>",
                              conferenceId);
  
                          // Create settings to determine how the party is connected to the conference room
                          ConferencePartyMuteDigits muteDigits = new ConferencePartyMuteDigits('*', '#');
                          ConferencePartyMediaSettings settings = new ConferencePartyMediaSettings(
                              null, null, false, '\0', muteDigits);
                          settings.SuppressDtmf = false;
  
  						// Uncomment this to start the party muted. 
                          // settings.StartMuted = true;
  
                          if (!channel.TransferToConferenceRoom(
                                  conferenceId, targetChannel, ConferencePartyType.TalkerAndListener,
                                  ConferenceLifetimeControl.FullControl,
                                  settings, 30))
                          {
                              channel.FilePlayer.Say("Failed to transfer to conference. Hanging up.");
                              channel.HangUp();
                          }
                      }
                      else
                      {
                          channel.FilePlayer.Say("No digits received. Hanging up.");
                          channel.HangUp();
                      }
                  }
  
                  // Wait for 10min for the call to be Idle
                  channel.WaitForIdle(60 * 10);
              }
              catch (Exception e)
              {
                  this.Trace.TraceError("Exception thrown {0}", e.Message);
                  reply = ReturnCode.ExceptionThrown;
              }
  
              this.Trace.TraceInfo("Completed");
              return (int)reply;
          }
      }
  }

• Filename:

  Samples\VB\AddToConference\AddToConference.vb

  Description:

  We ask for a four digit PIN code, representing the conference ID number, receive it using DTMF detection and then repeat the number back to the caller for confirmation. We can then use the channel.TransferToConference() method, that will manage the transfer for us, passing it one of the extra channels to use for the transfer. This conference is configured to produce silence on the line until someone else enters the conference.

  We construct a ConferencePartyMediaSettings object to allow us to disable DTMF suppression which is enabled by default. The conference is configured to produce silence on the line until someone else enters the conference room.

  Code:

  Imports AMSClassLibrary
  Imports UASAppAPI
  
  ' An inbound application that prompts the user to enter a 4-digit pin that represents 
  ' the id of a conference to which they are then transferred.
  '
  ' Note: this sample will only run on platforms that support Transfer.
  '
  ' Requires:
  ' [1 extra channel]
  Namespace AddToConference
  
      ' The application class.
      ' This must have the same name as the assembly and must inherit from either 
      ' UASInboundApplication or UASOutboundApplication.
      ' It must override the Run method.
      Public Class AddToConference
          Inherits UASInboundApplication
  
          ' Possible return codes
          Enum ReturnCode
              ' Success Codes:
              Success = 0
              ' ... any positive integer
  
              ' Fail Codes:
              ' -1 to -99 reserved
              ExceptionThrown = -100
              NotSufficientExtraChannels = -101
          End Enum
  
          ' This is the entry point for the application
          Overrides Function Run(ByVal channel As UASCallChannel, _
                                 ByVal applicationParameters As String) _
                                 As Integer
  
              Me.Trace.TraceInfo("Started")
              Dim reply As ReturnCode = ReturnCode.Success
              Dim conferenceId As String
  
              ' Check we've got an extra Channel
              If channel.ExtraChannels.Length < 1 Then
                  Me.Trace.TraceWarning("Needs 1 extra channel to be configured")
                  Return ReturnCode.NotSufficientExtraChannels
              End If
              Dim targetChannel = channel.ExtraChannels(0)
  
              Try
                  ' Answer the call
                  Dim state As CallState
                  state = channel.Answer()
  
                  If state = CallState.Answered Then
                      Me.Trace.TraceInfo("Call answered")
  
                      ' Prompt for a conference id, enabling bargein
                      channel.FilePlayer.Say("Please Enter a four digit conference i d.", True)
  
                      Dim digits As String = ""
                      Dim cause = channel.DtmfDetector.GetDigits(4, digits, 30)
                      If cause = DtmfDetectorCause.Count Then
                          conferenceId = digits
  
                          ' Inform the caller what is happening
                          channel.FilePlayer.Say( _
                              "Adding you to conference <say-as interpret-as='vxml:digits'>{0}</say-as>", _
                              conferenceId)
  
                          ' Create settings to determine how the party is connected to the conference room
                          Dim muteDigits = New ConferencePartyMuteDigits("*", "#")
                          Dim settings = New ConferencePartyMediaSettings(Nothing, Nothing, False, "\0", muteDigits)
                          settings.SuppressDtmf = False
  
                          ' Uncomment this to start the party muted. 
                          ' settings.StartMuted = True;
  
                          If Not channel.TransferToConferenceRoom( _
                                  conferenceId, targetChannel, ConferencePartyType.TalkerAndListener, _
                                  ConferenceLifetimeControl.FullControl, _
                                  settings, 30) Then
                              channel.FilePlayer.Say("Failed to transfer to conference. Hanging up.")
                              channel.HangUp()
                          End If
                      Else
                          channel.FilePlayer.Say("No digits received. Hanging up.")
                          channel.HangUp()
                      End If
                  End If
  
                  ' Wait for 10min for the call to be Idle
                  channel.WaitForIdle(60 * 10)
  
              Catch ex As Exception
                  Me.Trace.TraceError("Exception thrown {0}", ex.Message)
                  reply = ReturnCode.ExceptionThrown
              End Try
  
              Me.Trace.TraceInfo("Completed")
              Return reply
  
          End Function
  
      End Class
  
  End Namespace

UAS API - Connect To Conference Sample Application

• Python
• C#
• VB

• Filename:

  samples/connect_to_conference.py

  Description:

  This sample application will connect the caller to a conference room. Using channel.FilePlayer.say(), the application askes the caller to enter a four digit PIN, representing a conference room ID, channel.DTMFDetector.get_digits() is used to retrieve the digits. If the right number of digits has been collected, the application will call use the high level API function call_and_connect_to_conference() to connect the caller to the conference room. If the conference room does not already exist, it will be created. There will be silence on the line until someone else enters.

  Code:

  """
      An inbound application that prompts the user to enter a 4-digit pin that represents a 
      conference room, to which they are then connected. Please read the documentation about
      conference rooms.
  
      The application uses TTS to communicate with the caller.
  
      This application requires 1 extra channel.
  
      Actions:
          - wait for inbound call
          - wait for four DTMF digits
          - create a tone player
          - connect the call to the conference room
          - wait for the caller to hang up
  
  """
  
  from prosody.uas import Hangup, Error
  from prosody.uas.highlevel import HighLevelCallChannel
  
  __uas_identify__ = "application"
  __uas_version__  = "1.0b1"
  
  def main(channel, application_instance_id, file_man, my_log, application_parameters):
  
      return_code = 0
  
      try:
          if channel.state() == channel.State.CALL_INCOMING:
              channel.ring()   # this can raise a Hangup exception
              channel.answer() # this can raise a Hangup exception
          else:
              raise Hangup('No inbound call')
  
          # get the extra channel
          try:
              out_channel = channel.ExtraChannel[0]
          except:
              raise Error("You need to register an extra channel for this application")
  
          channel.FilePlayer.say("Please enter a four digit conference i d.", barge_in = True)
  
          digits = channel.DTMFDetector.get_digits(count=4, seconds_predigits_timeout = 10)
  
          if channel.DTMFDetector.cause() == channel.DTMFDetector.Cause.COUNT:
              channel.FilePlayer.say("Adding you to conference {0}".format(", ".join(digits)))
  
              high_level_channel = HighLevelCallChannel(channel, my_log)
              if high_level_channel.call_and_connect_to_conference(other_call=out_channel, 
                                                                   conference_room_name=digits) is False:
                  my_log.error("Connect to conference. Hanging up")
                  channel.FilePlayer.say ("Sorry, I could not connect you to your conference. Good bye")
                  return_code = -104
              else:
                  my_log.info ("Connect to conference {0} succeeded. Waiting for idle.".format (digits))
                  channel.wait_for_idle(seconds_timeout=None)
          else:
              channel.FilePlayer.say ("I did not receive four digits. Hanging up.")
              return_code = -103
              
      except Hangup as exc:
          my_log.info("Got Hangup")
          return_code = -100
  
      except Error as exc:
          my_log.error("Got Error {0}".format(exc))
          return_code = -102
  
      except Exception as exc:
          my_log.exception("Got unexpected exception {0}".format(exc))
          return_code = -101
  
      finally:
          if channel.state() != channel.State.IDLE:
              channel.hang_up()
      return return_code
  

• Filename:

  Samples\C#\ConnectToConference\ConnectToConference.cs

  Description:

  We ask for a four digit PIN code, representing the conference ID number, receive it using DTMF detection and then repeat the number back to the caller for confirmation. We can then use the CallConferenceRoom() method, that will call the conference on the extra channel supplied.

  We construct a ConferencePartyMediaSettings object to allow us to disable DTMF suppression which is enabled by default. The conference is configured to produce silence on the line until someone else enters the conference room.

  Code:

  using System;
  using System.Threading;
  
  using AMSClassLibrary;
  using UASAppAPI;
  
  // An inbound application that prompts the user to enter a 4-digit pin that represents 
  // the id of a conference to which they are then connected.
  //
  // Requires:
  // [1 extra channel]
  namespace ConnectToConference
  {
      // The application class.
      // This must have the same name as the assembly and must inherit from either 
      // UASInboundApplication or UASOutboundApplication.
      // It must override the Run method.
      public class ConnectToConference : UASInboundApplication
      {
          // Possible return codes
          enum ReturnCode
          {
              // Success Codes:
              Success = 0,
              // ... any positive integer
  
              // Fail Codes:
              // -1 to -99 reserved
              ExceptionThrown = -100,
              NotSufficientExtraChannels = -101
          }
  
          // This is the entry point for the application
          public override int Run(UASCallChannel channel,
                                  string applicationParameters)
          {
              this.Trace.TraceInfo("Started");
              ReturnCode reply = ReturnCode.Success;
              string conferenceId;
  
              // Check we've got an extra Channel
              if (channel.ExtraChannels.Length < 1)
              {
                  this.Trace.TraceWarning("Needs 1 extra channel to be configured");
                  return (int)ReturnCode.NotSufficientExtraChannels;
              }
              UASCallChannel conferenceChannel = channel.ExtraChannels[0];
  
              try
              {
                  // Answer the call
                  CallState state = channel.Answer();
                  if (state == CallState.Answered)
                  {
                      this.Trace.TraceInfo("Call answered");
  
                      // Prompt for a conference id, enabling bargein
                      channel.FilePlayer.Say("Please Enter a four digit conference i d.", true);
  
                      string digits;
                      DtmfDetectorCause cause = channel.DtmfDetector.GetDigits(4, out digits, 30);
                      if (cause == DtmfDetectorCause.Count)
                      {
                          conferenceId = digits;
  
                          // Inform the caller what is happening
                          channel.FilePlayer.Say(
                              "Adding you to conference <say-as interpret-as='vxml:digits'>{0}</say-as>",
                              conferenceId);
  
                          // Create settings to determine how the party is connected to the conference room
                          ConferencePartyMuteDigits muteDigits = new ConferencePartyMuteDigits('*', '#');
                          ConferencePartyMediaSettings settings = new ConferencePartyMediaSettings(
                              null, null, false, '\0', muteDigits);
                          settings.SuppressDtmf = false;
  
                          // Uncomment this to start the party muted. 
                          // settings.StartMuted = true;
  
                          if (conferenceChannel.CallConferenceRoom(
                              conferenceId,
                              ConferencePartyType.TalkerAndListener,
                              ConferenceLifetimeControl.FullControl,
                              settings,
                              30) == CallState.Answered)
                          {
                              // Connect the calls together
                              if (!channel.Connect(conferenceChannel))
                              {
                                  channel.FilePlayer.Say(
                                      "Failed to connect to conference. Hanging up.");
                                  channel.HangUp();
                              }
                          }
                          else
                          {
                              channel.FilePlayer.Say(
                                  "Failed to call conference <say-as interpret-as='vxml:digits'>{0}</say-as>. Hanging up.",
                                  conferenceId);
                              channel.HangUp();
                          }
                      }
                      else
                      {
                          channel.FilePlayer.Say("No digits received. Hanging up.");
                      }
                  }
  
                  // Wait for the call to be Idle
                  channel.WaitForIdle(360);
              }
              catch (Exception e)
              {
                  this.Trace.TraceError("Exception thrown {0}", e.Message);
                  reply = ReturnCode.ExceptionThrown;
              }
  
              this.Trace.TraceInfo("Completed");
              return (int)reply;
          }
      }
  }

• Filename:

  Samples\VB\ConnectToConference\ConnectToConference.vb

  Description:

  We ask for a four digit PIN code, representing the conference ID number, receive it using DTMF detection and then repeat the number back to the caller for confirmation. We can then use the CallConferenceRoom() method, that will call the conference on the extra channel supplied. This conference is configured to produce silence on the line until someone else enters the conference.

  We construct a ConferencePartyMediaSettings object to allow us to disable DTMF suppression which is enabled by default. The conference is configured to produce silence on the line until someone else enters the conference room.

  Code:

  Imports AMSClassLibrary
  Imports UASAppAPI
  
  ' An inbound application that prompts the user to enter a 4-digit pin that represents 
  ' the id of a conference to which they are then connected.
  '
  ' Requires:
  ' [1 extra channel]
  Namespace ConnectToConference
  
      ' The application class.
      ' This must have the same name as the assembly and must inherit from either 
      ' UASInboundApplication or UASOutboundApplication.
      ' It must override the Run method.
      Public Class ConnectToConference
          Inherits UASInboundApplication
  
          ' Possible return codes
          Enum ReturnCode
              ' Success Codes:
              Success = 0
              ' ... any positive integer
  
              ' Fail Codes:
              ' -1 to -99 reserved
              ExceptionThrown = -100
              NotSufficientExtraChannels = -101
          End Enum
  
          ' This is the entry point for the application
          Overrides Function Run(ByVal channel As UASCallChannel, _
                                 ByVal applicationParameters As String) _
                                 As Integer
  
              Me.Trace.TraceInfo("Started")
              Dim reply As ReturnCode = ReturnCode.Success
              Dim conferenceId As String
  
              ' Check we've got an extra Channel
              If channel.ExtraChannels.Length < 1 Then
                  Me.Trace.TraceWarning("Needs 1 extra channel to be configured")
                  Return ReturnCode.NotSufficientExtraChannels
              End If
              Dim conferenceChannel = channel.ExtraChannels(0)
  
              Try
                  ' Answer the call
                  Dim state As CallState
                  state = channel.Answer()
  
                  If state = CallState.Answered Then
                      Me.Trace.TraceInfo("Call answered")
  
                      ' Prompt for a conference id, enabling bargein
                      channel.FilePlayer.Say("Please Enter a four digit conference i d.", True)
  
                      Dim digits As String = ""
                      Dim cause = channel.DtmfDetector.GetDigits(4, digits, 30)
                      If cause = DtmfDetectorCause.Count Then
                          conferenceId = digits
  
                          ' Inform the caller what is happening
                          channel.FilePlayer.Say( _
                              "Adding you to conference <say-as interpret-as='vxml:digits'>{0}</say-as>", _
                              conferenceId)
  
                          ' Create settings to determine how the party is connected to the conference room
                          Dim muteDigits = New ConferencePartyMuteDigits("*", "#")
                          Dim settings = New ConferencePartyMediaSettings(Nothing, Nothing, False, "\0", muteDigits)
                          settings.SuppressDtmf = False
  
                          ' Uncomment this to start the party muted. 
                          ' settings.StartMuted = True;
  
                          If (conferenceChannel.CallConferenceRoom( _
                              conferenceId, _
                              ConferencePartyType.TalkerAndListener, _
                              ConferenceLifetimeControl.FullControl, _
                              settings, _
                              30) = CallState.Answered) Then
                              ' Connect the calls together
                              If Not channel.Connect(conferenceChannel) Then
                                  channel.FilePlayer.Say( _
                                      "Failed to connect to conference. Hanging up.")
                                  channel.HangUp()
                              End If
                          Else
                              channel.FilePlayer.Say( _
                                  "Failed to call conference <say-as interpret-as='vxml:digits'>{0}</say-as>. Hanging up.", _
                                  conferenceId)
                              channel.HangUp()
                          End If
                      Else
                          channel.FilePlayer.Say("No digits received. Hanging up.")
                          channel.HangUp()
                      End If
                  End If
  
                  ' Wait for 10min for the call to be Idle
                  channel.WaitForIdle(60 * 10)
  
              Catch ex As Exception
                  Me.Trace.TraceError("Exception thrown {0}", ex.Message)
                  reply = ReturnCode.ExceptionThrown
              End Try
  
              Me.Trace.TraceInfo("Completed")
              Return reply
  
          End Function
  
      End Class
  
  End Namespace