3/20/2024 0 Comments Creating minified js files![]() ![]() You can upload your source maps via the API. Add the script included in the Quick start browser section inside the tag in index.html. Once you have created an account and your first project, you’ll be given a client-side access token. Let’s dive into an example of how it works. Because rollbar,js supports source maps, you can see the line of exact code where each error originated along with the stack trace. Rollbar provides real-time production error monitoring with support for most programming languages and frameworks, including JavaScript, Angular, Node, React, etc. Do you want to make it easier for people you don’t know to see your raw source code? Fortunately, Rollbar supports using source maps to get meaningful stack traces while still using minified JavaScript in production. When you’re debugging a production application, it gets trickier since production servers often don’t serve source maps. For this demo, I created an AWS instance, installed an Apache Web Server, and served the web application from there. Note: To complete the next set of steps, you will need to have the JavaScript-calculator web application running on a publicly accessible web server. Let’s make it easier to identify and resolve this.Įrror within the minified JavaScript file If you open the index.html in Chrome or your browser of choice, you’ll notice that there is a JavaScript error which is thrown on the first line of our minified file. For now, let’s look at how to leverage the source map in production to make debugging easier. If you’d like to understand more about how the mappings work, and how they translate the minified code back to the source, I’d recommend reading How do source maps work. The useful part is the mappings, although unfortunately since they are in Base 64 VLQ, they’re not very useful for the human brain. The file specifies the mapping version used and identifies the source files and names of parameters. You can install UglifyJS with npm if you have that installed on your workstation.Įnter fullscreen mode Exit fullscreen mode I’m going to use UglifyJS, but most tools should support the ability to generate a production source map as part of the minification process. The first thing that we’ll need is a tool to minify the code. ![]() Keeping it simple will help keep the demo manageable, and the concepts apply to any application, no matter the size. If you already know how to generate a source map or just want to use the generated file, you can skip down to How Do Source Maps Work?įor this example, I’m going to be using a simple JavaScript application. ![]() The source includes the original JavaScript file, the minified JavaScript file, and the source map. You can download or clone the source for the following demo from. We’ll look at how to generate a source map, and then we’ll look at how they work, and how we can use them to make our lives easier. It also allows you to use your browser's developer console to step through the source code when debugging problems. By using the source map in production, you can trace your problems back to the exact line of source code. Source maps are generated when JavaScript code is minified. JavaScript source maps are the key to taking what you’ve narrowed down in the minified code, and then being able to map them back to the source code so that you can view and resolve the problem without having to figure it out in the minified code. I realized that I’ve managed to debug myself right into the middle of a minified JavaScript file □. I felt as though I was right on the edge of seeing the offending code and being able to fix it. One of the frustrating situations I often encounter when debugging JavaScript, is tracking down JavaScript errors to line 5. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |