How can you improve Angular web application performance with lazy loading?

3 How to optimize lazy loading in Angular?

Optimizing lazy loading in Angular requires considering some best practices and tools that can help you improve the performance and user experience of your application. For instance, you can use preloading strategies such as PreloadAllModules, NetworkAwarePreloadStrategy, or CustomPreloadStrategy to reduce latency and improve perceived performance. Additionally, performance budgets can be set to keep bundles and modules lightweight and fast, and configured in the angular.json file using the budgets property. Lastly, code splitting and tree shaking can be used to reduce the size of bundles and modules, as well as eliminate unused or redundant code. Webpack or Rollup are useful tools for performing code splitting and tree shaking.

4 How to test and measure lazy loading in Angular?

In order to test and measure lazy loading in Angular, you need to use specific tools and methods that can help you analyze the performance and behavior of your application. Chrome DevTools can be used to inspect and debug your application, as well as view the network requests and responses, the size and duration of each request, and the waterfall view of the sequence and timing of each request. Additionally, the Coverage tab can be used to see how much code is used or unused in your application, while the Performance tab shows CPU and memory usage, as well as frames per second (FPS). Angular CLI can be used to build and serve your application, with the --prod flag allowing for optimized and minified bundles and modules. Using the --stats-json flag generates a stats.json file, which contains detailed information about bundles and modules such as size, dependencies, and entry points. Webpack Bundle Analyzer or Source Map Explorer can be used to visualize this file. Lastly, Lighthouse audits your web application to provide recommendations and metrics on performance, accessibility, best practices, SEO, First Contentful Paint, Time to Interactive, Speed Index, and Total Blocking Time.

5 How to troubleshoot lazy loading in Angular?

Troubleshooting lazy loading in Angular requires an understanding of common issues and errors, as well as how to resolve them. One example is the 'Module not found' error, which may be caused by an incorrect path to the module file or the file itself being missing or corrupted. To fix this, you must check and correct the path to the module file, and ensure it exists and is valid. Another issue is 'Chunk load failed', which can be caused by a network request failing or the server returning an error. This can be remedied by checking and fixing the network connection, server configuration, and response status code. Lastly, 'No NgModule metadata found' might occur when the lazy module is not decorated with the @NgModule decorator, or when some of its properties are missing, such as imports, declarations, or exports. To fix this, you must add or update the @NgModule decorator for the lazy module and provide all necessary properties.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?