Category / Programming

by dmacias

Forward your VoIP Number to another phone and send text messages to email

Given the recent VOIPO shutdown announcement:

Screenshot 2025-08-04 at 2.11.18 PM

and the amount of attention this has gotten on r/voip I figured I would post this to help others who are looking for options. This will require a bit of technical knowledge, but I included every single step required so you could do this yourself. Please make sure you read the entire post before you get started.

What this solution does:

  1. If you receive a call on your phone number, it will be forwarded to a secondary number. The forward is completely blind, if you don’t answer the call it will do whatever your secondary number does when it doesn’t answer. There is no transcription or notification of any kind. It could be added, but that’s outside the scope of this post.
  2. If you receive an SMS message on your phone number, you will receive an email with the contents of said message. There is no response back to the original sender. There is no other notification other than the email you receive. The email will probably go to SPAM, but that’s easy to address.
  3. This has only been tested in the US. I have to imagine other countries would work similarly, but I can’t guarantee anything outside the US.
  4. This solution has no guarantees of any kind. I’ve been using something similar for maybe 10 years and have configured similar solutions for my customers for even longer. However, you are not my customer, but if you want to become my customer head on over to Square O to learn more or send us an email at hello at squareo.com.

Please note that there are NO affiliate links in this post.

Products Used:

  1. We are going to use Twilio for handling a phone call and SMS message. Think of Twilio as a programming platform for telephony services. You can control your calls and text messages with code. Twilio pricing is pretty excellent because it’s very transparent and you have per use charges. Twilio directly replaces VOIPo for example.
  2. We are going to use Mailgun for handling emails. Think of Mailgun as a programming platform for email services. All those promotional emails, news letters, etc. that you get in your inbox come from a provider like Mailgun.

Expected costs:

In our case, let’s assume we get a single call that’s 10 minutes long and 2 text messages. The pricing formula would look like this:

incoming minutes*total minutes + outgoing minutes*total minutes+incoming messages*total messages
($0.0085 / min*10)+($0.0140 / min*10)+($0.0083 / msg*2)=$0.2416 or about 2.5 cents USD.

Note that we are charged for the incoming call and the outgoing call, so we’re paying double for this. It’s important to be aware of this. This is a very common practice on pay as you go platforms.

For email: Mailgun has a very generous free tier of 100 emails per day. This means that if you receive more than 100 text messages per day you would have to sign up for their $15/month plan which allows for 10,000 emails/month. 

Now, there’s one more item which will incur costs and this is the phone number. If you buy a new number or port your number to Twilio you will be charge $1.15/month to hold each phone number. So our total charges based on the example above will be around $1.18/month.

Let’s start building. Prerequisites:

  1. A Mailgun account, you can sign up to a free account via this link.
  2. A Twilio account, you can sign up for a free account via this link. Please note that when you first open an account with Twilio you’re in Trial Mode. Your account needs to NOT be an trial account in order for this to work.
  3. You do not need to port your number until you have everything working, but once you do, you’ll need to submit a porting request. Instructions here.

Twilio Setup for Call Forwarding Only

  1. From the console you’ll want to find Services under Functions and Assets. If you have a new account you will more than likely have to go to Explore products > Developer tools > Functions and Assets.

f0116444-173b-424a-ba89-e90046424d33

2. You will want to Create Service and name it something logical. I chose forwarding-call-sms as my service name.
3. You will then be sent to the function page and see a /welcome in the right hand side. Click the 3 vertical dots and Delete.

Screenshot 2025-08-04 at 3.16.43 PM

4. Click the Add+ button > Add Function.
5.  Name your function /voice and copy and paste the following code.

exports.handler = function(context, event, callback) {
// IMPORTANT: Replace the placeholder number below with your actual forwarding phone number (digits only).

let yourDefaultForwardingNumber = “15551231234”;

// Set the destination phone number.
// It will use the number from the incoming event if it exists,
// otherwise it constructs the full number from your default.
let destinationPhoneNumber = event.PhoneNumber || `+${yourDefaultForwardingNumber}`;

// Generate the TwiML to tell Twilio how to forward this call
let twiml = new Twilio.twiml.VoiceResponse();

let dialParams = {};

// The <Dial> TwiML verb is used to connect the current call to a new number
twiml.dial(dialParams, destinationPhoneNumber);

// Return the TwiML to Twilio
callback(null, twiml);
};

6. Update the line that start with let yourDefaultForwardingNumber with your 10 digit phone number starting with 1.
7. Hit Save
8. Hit Deploy All and you should see something like this.

Aug 4, 2025, 03:24:33 PM Saving function path: /voice…
Aug 4, 2025, 03:24:34 PM Saved function: /voice
Aug 4, 2025, 03:24:46 PM Starting build…
Aug 4, 2025, 03:24:47 PM Completed…
Aug 4, 2025, 03:25:02 PM Build completed
Aug 4, 2025, 03:25:02 PM Deploying…
Aug 4, 2025, 03:25:03 PM Deployed to environment: forwarding-call-sms-…

9. From the console you’ll want to find the Buy a number under Phone Numbers > Manage. You can choose different types of phone numbers based on all sorts of criteria. To get started pick any local number that supports Voice and SMS. Once purchased you’ll want to go to Active Numbers and click on it to configure the function we wrote to be triggered every time a call arrives.

2c2cc12b-b311-43e8-bfcf-77ba030d45a7
10.Under Voice Configuration you’ll want your configuration to look like this.

Screenshot 2025-08-04 at 3.32.16 PM

11. Click Save configuration and you are done. 
12. Place a test call and see what happens.

Mailgun and Twilio Setup for Call SMS to Email Only

  1. Login to your Mailgun dashboard and go to Sending > Domains. The domain should look something like sandboxXYZ.mailgun.org. Copy the domain and save it for later use.
  2. Click on your sandbox domain and go to Setup.
  3. Add the email address of who will receive the SMS emails and send invite. You must click on the I Agree link you get in your inbox to ensure emails will be sent to you via Mailgun.

Screenshot 2025-08-04 at 11.04.20 PM

3. Under Sending keys add a sending key and copy the Sending API key and save it for later use.
4. Go back to Twilio > Functions and click on the function you used on the first step.
5. Add a new function called /sms and add the following code and Save.

exports.handler = function(context, event, callback) {
constAPI_KEY = context.MAILGUN_API_KEY;
constDOMAIN = context.MAILGUN_DOMAIN;

const formData = require(‘form-data’);
constMailgun = require(‘mailgun.js’);

const mailgun = newMailgun(formData);
const client = mailgun.client({username: ‘api’, key: API_KEY});

const messageData = {
from: context.FROM_EMAIL,
to: context.TO_EMAIL,
subject: `New SMS message from: ${event.From}`,
text: event.Body
};

client.messages.create(DOMAIN, messageData)
.then((res) => {
let twiml = newTwilio.twiml.MessagingResponse();
callback(null, twiml);
})
.catch((err) => {
console.error(err);
callback(err);
});
};
6. Click on Dependencies and add the following two exactly as you see the below.

mailgun.js

11.1.0

form-data4.0.1

7. Click on Environment Variables and add the following 4 variables with your respective values.

FROM_EMAIL

your@email.com

TO_EMAILyour@email.com
MAILGUN_API_KEY

Key saved from step 3 above.

MAILGUN_DOMAINDomain saved from step 1.

8. Deploy all
9. From the console you’ll want to find your phone number under Phone Numbers > Manage. You’ll want to set up your messaging configuration to look like this.

Screenshot 2025-08-04 at 11.35.41 PM

10. Click Save configuration and you are done. 
11. Send a text message to your Twilio number and check your spam folder. You should see an email like the one below.

 

Screenshot 2025-08-04 at 11.32.51 PM

Good luck.

~david

 
by dmacias

Find specific phone number in Finesse phone books through the Finesse API using Python

A quick script that goes through every phone book looking for a specific number.

Here’s a quick Python script that will allow you to go through each phone book in Finesse and identify the phone book that has the phone number(s) you’re after. Just fill in your information ‘<>’ and update the numbers you want to find.

import requests # for using API
from requests.auth import HTTPBasicAuth
import xml.etree.ElementTree as ET # for parsing XML

requests.packages.urllib3.disable_warnings() #If using a self signed certificate

rootURL = ‘<>’ # e.g. http://finesse.company.com
phonebooksURL = ‘/finesse/api/PhoneBooks’
username = ‘<>’ #Finesse admin username
password = ‘<>’

headers = {‘Accept’: ‘application/xml’, ‘Content-Type’: “application/xml”}

phonenumbers = [‘5555551234’, ‘5555551235’, ‘5555551236’, ‘5555551237’] #phone numbers you want to find.

res = requests.get(rootURL+phonebooksURL, headers= headers, verify=False, auth=HTTPBasicAuth(username, password))
print(res.status_code)

root = ET.fromstring(res.content)

for phonebooks in root:
phonebookId = phonebooks[3].text
res = requests.get(rootURL+phonebookId+’/Contacts’, headers=headers, verify=False, auth=HTTPBasicAuth(username, password))
print(res.status_code)
root = ET.fromstring(res.content)
for contacts in root:
for number in phonenumbers:
if number in contacts[3].text:
print(phonebooks[2].text, contacts[3].text)

~david

by dmacias

Adding Text to Speech to Your IVR Using SaaS (Google Cloud Functions)

A bit of code to allow your on premise IVR to have TTS using a cloud function.

I’ve been on a text-to-speech and speech-to-text kick lately. My last post talked about using AWS S3 and Amazon Transcribe to convert your audio files to text and in previous articles I’ve covered how to create temporary prompts using Poly so you can build out your contact center call flows. Well, now we’re going to expand our use case to allow a traditional on premise call center to leverage the cloud and provide dynamic prompts. My use case is simple. I want my UCCX call center to dynamically play some string back to my caller without having to use a traditional TTS service.

First, this is not new in any way and other people have solved this in different ways. This Cisco DevNet Github repo provides a method to use voicerss.org to generate TTS for UCCX. However, this process requires loading a jar file in order to do Base64 decoding. Then there’s this Cisco Live presentation from 2019, by the awesome Paul Tindall, who used a Connector server to do something similar. To be fair the Connector server allowed for a ton more functionality than what I’m looking for.

Screen Shot 2021-09-15 at 3.38.30 PM

Cisco Live Presentation

Second, I wanted this functionality to be as easy to use as possible. While functionality keeps getting better for on premise call center software there are still limitations around knowledge to leverage new features and legacy version that can’t be upgraded that makes it harder to consume cloud based services. I wanted the solution to require the least amount of moving parts possible. That means no custom Java nor additional servers to stand up.

The solution I came up with leverages Google’s cloud (GCP) specifically Cloud Functions. However, the same functionality can be achieves used AWS Lambda or Azure’s equivalent. At a high level we have an HTTP end point where you pass your text string to and in return you will get a wav file in the right format which you can then play back.

Blank diagram

Flow Diagram

The URL would look something like this:

https://us-central1-myFunction.cloudfunctions.net/synthesize_text_to_wav?text=American%20cookies%20are%20too%20big

The Good Things About This

  • Pay as you go pricing for TTS. Looking at the pricing calculator a few hours of TTS a month would run under $2.00/month.
  • Infinitely scalable. If you’re handling 1 call or 100 calls your function will always return data.
  • Easy to use.

The Bad Things About This

  • There is a delay between making the request and getting the wav file. I’ve seen as long as 7 seconds at times. I would only use this in a very targeted manner and ensure it didn’t affect the caller experience too drastically.
  • Requires your on premise IVR to have internet access. Often time this is a big no no for most businesses.

Some initial testing with UCCX is showing some positive results. I’m going to investigate if there’s a way to accelerate the processing in order to keep the request and response in under 3 seconds as well as adding the ability to set language, voice, and even SSML via arguments. If you want to build this yourself here’s the code for the function.

def synthesize_text_to_wav(request):
"""Synthesizes speech from the input string of text."""
text = request.args.get('text')

client = texttospeech.TextToSpeechClient()
input_text = texttospeech.SynthesisInput(text=text)
voice = texttospeech.VoiceSelectionParams(
language_code="en-US",
name="en-US-Standard-C",
ssml_gender=texttospeech.SsmlVoiceGender.FEMALE,
)
audio_config = texttospeech.AudioConfig(
audio_encoding=texttospeech.AudioEncoding.MP3
)
response = client.synthesize_speech(
request={"input": input_text, "voice": voice, "audio_config": audio_config}
)

src_file_path = '/tmp/output.mp3'
dst_file_path = '/tmp/output.wav'

# make sure dir exist
os.makedirs(os.path.dirname(src_file_path), exist_ok=True)

# The response's audio_content is binary.
with open(src_file_path, "wb") as out:
out.write(response.audio_content)
print('Audio content written to file "output.mp3"')
AudioSegment.from_mp3(src_file_path).export(dst_file_path, format="wav", codec="pcm_mulaw", parameters=["-ar","8000"])
return send_file(dst_file_path

Be awesome!

~david

by dmacias

Transcribe Your Audio Files To Migrate to Amazon Connect

This is an update to an earlier post covering the same thing now with updated code.

As we are working our way out of Cisco UCCE to Amazon Connect we find ourselves needing to transcribe thousands of prompts. I wanted to revisit this piece of code to ensure it is still working. If you want to use this and are starting from scratch here are the steps you need to take:

– Install Studio Code
– Install Python 3.9
– Create the folder where you will keep your project.
– Create a virtual environment.
– Activate your virtual environment.
– pip install python-dotenv, boto3, pandas
– *Remove the profile_name or update it.
– Update the .env file with the region you’ll be using.

You can find the full source code here.

The script works like this: It creates an S3 bucket, grabs the first file, checks if the file is in S3 and uploads it, creates a transcription job, waits for the transcription to complete, grabs the results, writes a CSV. I’ve tried to catch as many potential errors as possible, but I’m sure there are some lingering. Expect the transcription to take around 1 minute per file. Assuming normal IVR prompts.

AWS Transcribe* I have many AWS profiles, which might not the be case for others. If you only have a single profile change this line session = boto3.session.Session(profile_name=’MyProfile’) to session = boto3.session.Session()

I hope this helps others.

~david

by dmacias

Using AWS Transcribe to get IVR prompt verbiage

A bit of code to get verbiage out of prompts.

I’m a stickler for documentation and a bigger stickler for good documentation. Documentation allows the work you’ve produced to live on beyond you and help others get up to speed quickly. It feels that documentation is one of those things everyone says they do, but few really follow through. There’s nothing hard about it, but it’s something you need to work on as you’re going through your project. Do not leave documentation to the end, it will show. So DO IT!

I’ve recently started a new project to migrate an IVR over to CVP. To my pleasant surprise the customer had a call flow, prompts, a web service definition document, and test data. A dream come true! As I started the development I noticed that the verbiage in the prompts didn’t match the call flow and considering my “sticklerness” I wanted to update the call flow to ensure it matches 100% with the verbiage.

I’m always looking for excuses to play around with Python, so that’s what I used. I hacked together the script below which does the following:

  • Creates an AWS S3 bucket.
  • Uploads prompts from a specific directory to bucket.
  • Creates a job in AWS Transcribe to transcribe the prompts.
  • Waits for the job to be completed.
  • Creates a CSV names prompts.csv
  • Deletes transcriptions jobs
  • Deletes bucket

The only things you will need to change to match what you’re doing is the following:

local_directory = 'Spanish/'
file_extension = '.wav'
media_format = 'wav'
language_code = 'es-US'

The complete code is found below, be careful with the formatting it might be best to use copy it from this snippet:

</pre>
<pre>from __future__ import print_function
from botocore.exceptions import ClientError

import boto3
import uuid
import logging
import sys
import os
import time
import json
import urllib.request
import pandas

local_directory = 'French/'
file_extension = '.wav'
media_format = 'wav'
language_code = 'fr-CA'

def create_unique_bucket_name(bucket_prefix):
    # The generated bucket name must be between 3 and 63 chars long
    return ''.join([bucket_prefix, str(uuid.uuid4())])

def create_bucket(bucket_prefix, s3_connection):
    session = boto3.session.Session()
    current_region = session.region_name
    bucket_name = create_unique_bucket_name(bucket_prefix)
    bucket_response = s3_connection.create_bucket(
        Bucket=bucket_name,
    )
    # print(bucket_name, current_region)
    return bucket_name, bucket_response

def delete_all_objects(bucket_name):
    res = []
    bucket = s3Resource.Bucket(bucket_name)
    for obj_version in bucket.object_versions.all():
        res.append({'Key': obj_version.object_key,
                    'VersionId': obj_version.id})
    # print(res)
    bucket.delete_objects(Delete={'Objects': res})

s3Client = boto3.client('s3')
s3Resource = boto3.resource('s3')
transcribe = boto3.client('transcribe')
data_frame =  pandas.DataFrame()

# Create bucket
bucket_name, first_response = create_bucket(
    bucket_prefix = 'transcription-',
    s3_connection = s3Client)

print("Bucket created %s" % bucket_name)

print("Checking bucket.")
for bucket in s3Resource.buckets.all():
    if bucket.name == bucket_name:
        print("Bucket ready.")
        good_to_go = True

if not good_to_go:
    print("Error with bucket.")
    quit()

# enumerate local files recursively
for root, dirs, files in os.walk(local_directory):
    for filename in files:
        if filename.endswith(file_extension):
            # construct the full local path
            local_path = os.path.join(root, filename)
            print("Local path: %s" % local_path)
            # construct the full Dropbox path
            relative_path = os.path.relpath(local_path, local_directory)
            print("File name: %s" % relative_path)
            s3_path = local_path
            print("Searching for %s in bucket %s" % (s3_path, bucket_name))
            try:
                s3Client.head_object(Bucket=bucket_name, Key=s3_path)
                print("Path found on bucket. Skipping %s..." % s3_path)
            except:
                print("Uploading %s..." % s3_path)
                s3Client.upload_file(local_path, bucket_name, s3_path)
                job_name = relative_path
                job_uri = "https://%s.s3.amazonaws.com/%s" % (
                    bucket_name, s3_path)
                transcribe.start_transcription_job(
                    TranscriptionJobName=job_name,
                    Media={'MediaFileUri': job_uri},
                    MediaFormat=media_format,
                    LanguageCode=language_code
                )
                while True:
                    status = transcribe.get_transcription_job(TranscriptionJobName=job_name)
                    if status['TranscriptionJob']['TranscriptionJobStatus'] in ['COMPLETED', 'FAILED']:
                        break
                    print('Transcription ' + status['TranscriptionJob']['TranscriptionJobStatus'])
                    time.sleep(25)
                print('Transcription ' + status['TranscriptionJob']['TranscriptionJobStatus'])
                response = urllib.request.urlopen(status['TranscriptionJob']['Transcript']['TranscriptFileUri'])
                data = json.loads(response.read())
                text = data['results']['transcripts'][0]['transcript']
                print("%s, %s "%(job_name, text))
                data_frame = data_frame.append({"Prompt Name":job_name, "Verbiage":text}, ignore_index=True)
                print("Deleting transcription job.")
                status = transcribe.delete_transcription_job(TranscriptionJobName=job_name)

#Create csv
print("Writing CSV")
data_frame.to_csv('prompts.csv', index=False)

# Empty bucket
print("Emptying bucket.")
delete_all_objects(bucket_name)

# Delete empty bucket
s3Resource.Bucket(bucket_name).delete()
print("Bucket deleted.")</pre>
<pre>

I hope this helps someone out there create better documentation.

~david