Node.js is an open-source, cross-platform, JavaScript run-time environment that executes JavaScript code outside of a browser. Node.js lets developers use JavaScript to write command line tools and for server-side scripting—running scripts server-side to produce dynamic web page content before the page is sent to the user’s web browser. Consequently, Node.js represents a “JavaScript everywhere” paradigm, unifying web application development around a single programming language, rather than different languages for server- and client-side scripts.
You have a bunch of online services that let you take screenshots of a site and save them in a folder. While it can be very useful to pay for such a system, it is not so hard to create it. Let’s use Chrome / Chromium with Puppeteer and Node.js (cluster) to take some snapshots in no-time. We’ll use the Puppeteer Cluster package to run multiple threads / workers to grab those screens in parallel. We’ll be using TypeScript.
The web is unreliable. Here’s a compact exponential back-off retry utility for TypeScript — one function, no dependencies, proportional jitter included.
This week we had to exfil some data out of a bucket with 5M+ of keys. After doing some calculations and testing with a Bash script that used AWS cli, we decided to go a more performant route and use s3p. They claim to be 5-50 times faster than AWS cli 😊.
I’ve tried to use the ngrok npm package in my application, but as the documentation says: “The ngrok and all tunnels will be killed when node process is done.” I need the process to “survive” my application. Let’s see what we can do about that…
I love SVG, but sometimes they are hard to create, especially when you need to visualize diagrams. HTML is way easier to program. So why not combine them? Can we use HTML to generate an SVG? And can we use JsFiddle to generate that HTML?
Slack is fully awesome. At Wehkamp we use it for our internal communication and as a tool for our DevOps. The Slack API allows us to build even more advanced integrations. In this blog I’ll explore how to use the API to create powerful progress indicators by updating a Slack message.
To give teams a jump start we’ve created the bot-zero open source project. It solves some setup and development problems. In this blog I’ll show how to get up and running in minutes and I’ll explain some of the choices we’ve made.
Lately we’ve been playing around with ChatOps at Wehkamp. We added a Hubot to our Slack channels to automate some operational jobs. It makes work more fun and way easier. As it is hosted in our own infrastructure, it can interact with our micro-services. In this article I explore how to use ES6 and a Promise to implement a call to a simple web-service.
TypeScript allows for better JavaScript development. JavaScript is getting useful in more domains. But different systems require different ways of handling modules and exposing features. TypeScript solves this by compiling differently when a target is specified.
But what if you need a TypeScript script that supports both vanilla browser JS and Node.js? What if you need to expose 10+ classes?
Recently I’ve been playing around with NPM. I switched my unit tests from QUnit to Mocha. This was not as straight forward as one would hope. In this blog I’ll show some example code. At the end I’ll link to a side by side comparison of the entire test project. Hopefully it helps you to convert your code. I’ll be using the Chai BDD assertion engine.