Recently, I was tasked with writing some code to generate Excel workbooks containing sales data. I implemented the code using a Node module called ExcelJS. I found that this module provides a simple interface to generating documents, and it also supports more advanced functions such as text formatting, borders, formulae, and more. Read more on Generating Excel Files using Node.js and ExcelJS…
Platforms & Languages
Using Angular Content Projection to Draw Smiley Faces
When working in Angular, it’s pretty straightforward to create components and nest those components inside of other components. However, it is a bit more complicated to design customizable components that will display content based on the components passed to them (content projection). Read more on Using Angular Content Projection to Draw Smiley Faces…
A Pattern for Redux Thunk Async Actions
Redux is a powerful tool for structuring front-end logic, and Redux Thunk extends its capabilities to support asynchronous actions in a simple way. However, without a clear, consistent, and reusable pattern to follow, it’s easy for a team to write Thunk actions in different ways and add mental strain to understanding the codebase. Read more on A Pattern for Redux Thunk Async Actions…
Creating Custom CloudWatch Alarms for AWS Lambdas
AWS allows you to setup CloudWatch alarms on many performance-related metrics. Doing this for metrics like CPU load or storage use is trivial. However, setting up custom alarms based on events or errors in a log isn’t as straightforward. By the end of this post, you should know how to set up alarms based on errors and events within a Lambda on AWS. Read more on Creating Custom CloudWatch Alarms for AWS Lambdas…
Pattern Matching without Regex! – Introducing the Rosie Pattern Language
Recently, I was able to attend Jamie Jenning’s talk on the Rosie Pattern Language (RPL/“Rosie”) at Strange Loop 2018. I had not previously been aware of Rosie, but after learning about it, I am extremely excited about the prospect of never writing another regular expression again. Read more on Pattern Matching without Regex! – Introducing the Rosie Pattern Language…
An Introduction to Content Localization in Android Apps
When creating any kind of application, it’s important to build it for the users you expect to be supporting. Because of this, it may be necessary to display different strings, images, and other content based on the language or region of your users.
While creating the translations of an app can be a lengthy process, enabling content localization in an Android app is as simple as adding new files and folders to your resources. Read more on An Introduction to Content Localization in Android Apps…
CSS-Animated Countdown Timer with React and TypeScript
A while ago, on an old project, we needed to implement a countdown timer. The specified design looked relatively simple: an outline of a circle with the number of seconds remaining inside. As the time counted down, the text would need to update, and the stroke around the circle would need to disappear at an appropriate rate so it would be completely gone when the time got to zero seconds.
I originally implemented this timer in an Ember project. For the past year, I’ve been working with React, so I decided to try my hand at re-implementing it as a React component. Read more on CSS-Animated Countdown Timer with React and TypeScript…
Using an Int Type in TypeScript
The project I’m working on has a Node.js back end written in TypeScript, with a PostgreSQL database for persistence. We had a production user who encountered an error when the system tried to insert a row into a table that had an integer column in it. The value it was trying to insert was 239.99999999999997, so it made sense that PostgreSQL was complaining about it being “invalid input syntax for an integer.”
A Library for Driving NeoPixels with the ESP32 Micro Controller
The NeoPixel is a very cool little device. It combines three LEDs (red, green, and blue) with a specialized microprocessor, all in a package about the same size as a traditional LED. These smart LEDs open up a wide range of new project possibilities because they reduce the amount of circuitry and processor pins that would otherwise be necessary to drive an array of lights. Read more on A Library for Driving NeoPixels with the ESP32 Micro Controller…
Unit Testing Custom Xamarin.Forms Controls
When using Xamarin.Forms, the conventional wisdom is that you write unit tests around the ViewModel, but not the View. This approach works well for most cases with MVVM, but if you’re developing custom controls, it’s likely not sufficient. In this post, I’m going to dive into a bit of what it takes to successfully write unit tests around custom Xamarin.Froms controls.