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It happened! I've been waiting for the moment I needed to send a fax since Twilio launched the Programmable Fax API back in 2017 and this week it finally happened! I won't go into detail about what I needed to send, but it's safe to say the medical profession could consider their communication choices for the future.
I could have sent the fax by uploading a PDF to Twilio Assets and using the API explorer, but that wouldn't have been as fun as over-engineering an entire application to send and track the fax to make sure it arrived and be prepared for any future fax situations.
In this post I'll share how to build an application for sending and tracking faxes, but if you have faxes to send and want to jump straight into using it, you can find all the source code on GitHub.
Weapons of choice …
When your application sends emails it is useful to know what happens to those emails, like whether it has been delivered or opened. Or, sometimes more importantly, whether it bounced. The Twilio SendGrid email API doesn't just send emails, it can also send you events via webhook that tell you what happened to your emails.
In this post we'll build a small application using Ruby on Rails to send emails and update their status based on the Twilio SendGrid event webhooks.
What you'll need
In order to build this application along with this post, you will need:
- Ruby and Bundler installed
- ngrok - my favourite way to tunnel webhooks to my local machine
- A Twilio SendGrid account (if you don't have one, you can sign up for a free SendGrid account now)
If you have all of that, then you're ready to get building.
Preparing the example application
I …
We've seen a video chat built in React on this blog before but since then, in version 16.8, React released Hooks. Hooks let you use state or other React features inside functional components instead of writing a class component.
In this post we are going to build a video chat application using Twilio Video and React with only functional components, using the useState, useCallback, useEffect and useRef hooks.
What you'll need
To build this video chat application you will need the following:
- Node.js and npm installed
- A Twilio account (sign up for a free Twilio account here)
Once you've got all that, we can prepare our development environment.
Getting started
So we can get straight to the React application, we can start with the React and Express starter app I created. Download or clone the starter app's "twilio" branch, change into the new directory and …
The Web Speech API has two functions, speech synthesis, otherwise known as text to speech, and speech recognition. With the SpeechSynthesis API we can command the browser to read out any text in a number of different voices.
From a vocal alerts in an application to bringing an Autopilot powered chatbot to life on your website, the Web Speech API has a lot of potential for web interfaces. Follow on to find out how to get your web application speaking back to you.
What you'll need
If you want to build this application as we learn about the SpeechSynthesis API then you'll need a couple of things:
- A modern browser (the API is supported across the majority of desktop and mobile browsers)
- A text editor
Once you're ready, create a directory to work in and download this HTML file and this CSS file to it. Make …
On the web we can capture media streams from the user's camera, microphone and even desktop. We can use those media streams for real time video chat over WebRTC and with the MediaRecorder API we can also record and save audio or video from our users directly in a web browser.
To explore the MediaRecorder API let's build a simple audio recorder app with just HTML, CSS and JavaScript.
Getting started
To build this application all we need is a text editor and a browser that supports the MediaRecorded API. At the time of writing, supported browsers include Firefox, Chrome and Opera. There is also work ongoing to bring this API to Edge and Safari.
To get started, create a folder to work in and save this HTML file and this CSS file to give us something to start with. Make sure they are in the same folder …
When AWS launched Lambda in 2014 there was no love for Ruby. Platforms like Python, Node.js, and Java started the serverless revolution for hosting and running functions in the cloud. At the end of 2018, support for Ruby was finally launched.
You can build with Ruby on Lambda using raw functions and Serverless Application Model (SAM) templates as described in the getting started guide for Ruby on Lambda, but Ruby is all about developer happiness and when the config file is longer than your program the process could be described as painful. Enter the Jets framework a framework that "leverages the power of Ruby to make serverless joyful for everyone."
From Rails to Jets
Jets combines the experience of building a Rails application with the ability to deploy to AWS Lambda and related services, including API Gateway, S3, and DynamoDB. In this post we're going to …
With the Twilio API for WhatsApp we can send messages to WhatsApp numbers. Those messages can be plain text or include files like images, audio and even PDFs up to 5MB. Let's see how to do so using Ruby.
Things you'll need
If you want to code along with this post, you'll need a few things:
- A Twilio account (sign up for a free account now)
- Ruby and Bundler installed
- The WhatsApp Sandbox Channel installed (learn how to activate your WhatsApp sandbox)
Got all that? Let's get coding then!
Create a new directory for your project and use Bundler to initialise a new Gemfile:
mkdir whatsapp-messages cd whatsapp-messages bundle init
Open up the new Gemfile and add the tw …
If you're building a Twilio project you will inevitably need to run some code in response to an incoming webhook request. One of the easiest ways to do this is with Twilio Functions, our serverless platform for running Node.js. Recently my colleague Dominik released the twilio-run package that makes it easier to develop, test and debug Twilio Functions locally.
I wanted to make it even easier to get started with a Twilio Functions project, so I built a project generator called create-twilio-function.
Let's take a look at how you can easily start and develop a Twilio Functions project using create-twilio-function and twilio-run.
Getting started
There are a few ways you can use create-twilio-function. The easiest is if you have npm version 6 or higher. You can check this out on the command line with:
$ npm --version 6.9.0
If you don't have an up to …
Did you know you can send and receive media using the Twilio API for WhatsApp? When I found out I wanted to make something fun with it, so why not combine it with AWS Rekognition to work out if I look like any celebrities?
By the end of this post, you'll know how to build an app that lets you send an image to a WhatsApp number, download the image, analyse the image with the AWS Rekognition API and respond to say whether there are any celebrities in the picture.
What you'll need
To build this application you'll need a few things:
- A Twilio account, sign up for a free one here
- An AWS account
- Ruby and Bundler installed
- ngrok to help us test our webhooks
Got all that? Let's get started then.
Application basics
When Twilio receives a WhatsApp message it will send an HTTP request, a webhook …
Have you ever needed to download and save an image in your Ruby application? Read on to find out how.
Plain old Ruby
The most popular way to download a file without any dependencies is to use the standard library open-uri.
Kernel#open is a method that you can use to open files, streams, or processes to read to or write from. For example, you can open a file and read its contents with the following code:
open("./test.txt") do |file| puts file.read end
open-uri extends Kernel#open so that it can open URIs as if they were files. We can use this to download an image and then save it as a file.
To do so, we first require open-uri then use the open method to access an image URL. We can then open up a file and write the contents of the image …