Performant applications need to do three things well. Want to know mine? High performance with no downtime. What’s the fanciest, most amazing, and sexy feature you can add to your Node.js application? What is the most important feature your Node.js application can have? Do you think it’s having fancy fuzzy logic for your full-text search, or maybe using sockets for real-time chats? You tell me. Application Performance Monitoring Guide.Let’s give that a try: const fs = require('fs') Ĭonst buttonPressesLogFile = './button-presses.log' Ĭonsole.log(`Watching for file changes on $`) įs. The callback listener will be invoked each time the file is changed. The built-in fs-watchFile method seems like a logical choice to watch for changes in our log file. We’re using log-timestamp purely for educational purposes and is not necessary for any production-ready solutions.
#Node file monitor code
The log-timestamp package prepends the timestamp to any messages that we log to the console using console.log and enables us to see the timing of the file watching events that our code generates.
#Node file monitor install
Next, install the log-timestamp package from NPM and save it as a dependency in the package.json file: $ npm install -save log-timestamp Run the following command to create a package.json file for Node.js: $ npm init -y For starters, create a folder and navigate into that folder from the terminal. To explore Node’s different file watching options, let’s first set up a project.
#Node file monitor how to
These are both excellent packages that leverage Node’s built-in file watching functionality.įor those that want to learn how to use Node’s built-in file watching capabilities and get a little closer to the metal, keep reading! First steps If you’d rather install an npm package and move on, I’d recommend either chokidar or node-watch. Truth to be told, file watching can be accomplished without taking a dependency on an external package.
Our next challenge is to watch this log file for changes as button pushes are streamed in from one of our three sources (Amazon dash button, circuit board push-button, Web button) and take action. The resulting log file looks like this: 19:06:48|circuit board The feeding times are logged to a file by pressing a push-button on a circuit board connected to a Raspberry Pi, pressing an Amazon Dash button, or clicking a button through a web interface. In a previous article on counting unique items in a JavaScript array, I introduced you to the system I am creating that enables our family to log when the fish 🐟 in our aquarium have been fed.
0 kommentar(er)
