Lightning Web Component Debugging Solutions

Lightning Web Components (LWC) are powerful and reusable components for Lightning Experience and other websites that use modern web development standards such as HTML and JavaScript. However, as with any development effort, debugging and troubleshooting can be time-consuming.

In this article, we will look at several solutions for debugging LWC, as well as their benefits and drawbacks.

Browser Developer Tools (Unlimited)

Using the browser’s developer tools is one of the most basic and widely used ways to debug LWC and the frontend in general. Most modern web browsers include developer tools for debugging LWC.

Google Chrome’s developer tools are the most commonly used, and can be accessed by right-clicking on a web page and selecting Inspect or by pressing F12 on the keyboard. These tools provide extensive information about the component, including HTML, CSS, and JavaScript. You can also use the browser’s built-in debugging tools to set breakpoints in the JavaScript code of your component, step through the code, and see the values of variables at various points during execution.

Top Chrome DevTools Functions for LWC DOM Tree Debugging:

The Elements tab provides information about the component structure and can be used to locate any unusual elements or nodes. Developers can view a component’s attributes, style, and any child components that have been added by viewing the DOM Tree.

The Console tab

This can be used to log any errors or warnings that occur in the application. It aids in the resolution of any issues that arise during development.

The Sources panel

allows developers to view and set breakpoints in their application’s source code. This can be useful for debugging code issues or inspecting the state of the application at any time.

The Performance panel

it displays information about the application’s performance. It aids in identifying potential performance issues or monitoring the application’s performance over time.

The Network tab

It allows developers to see all of the requests sent to the server as well as any responses that have been received. This can help you identify any requests that are taking longer than expected or are failing to complete successfully.

Extension for Salesforce Lightning

The Lightning Web Components Inspector is another useful tool for debugging LWC. It is a browser extension for Google Chrome that allows you to inspect LWC on the page and see the component’s properties and state, as well as the component’s events and their associated handlers.

One of the most useful features of this extension is the ability to see all the calls to the servers (Actions tab) with sent parameters and return values, as well as errors (if they took place). It has less functionality than Chrome Dev Tools and cannot copy values from the Actions tab, but the UI is very clear and understandable for beginners. More information and the extension can be found in the Chrome Web Store.

Playgrounds Online

An online playground is an excellent tool for debugging and validating simple Lightning Web Components with few dependencies on other components. These playgrounds enable developers to experiment with LWC without having to deploy them to a Salesforce org.

Furthermore, online playgrounds offer a visual interface for developers to interact with the component, allowing them to see the effects of changes in real time. Overall, online playgrounds are a good solution for debugging LWC code when you need to test a component in isolation or want to see the results of your code changes quickly.

Remember that the playground environment may not always correspond to the environment of the actual Salesforce org where the component will be deployed. When the component is deployed to a production org, this can result in unexpected behavior or errors. It is always a good idea to validate the code in an organization and run the test cases.

Webcomponents.dev is one of the playgrounds recommended by Salesforce.

Direct Debugging in the IDE

Our LWC code can also be debugged directly from the IDE. Jest tests can be written to cover the logic and markup of your components. You can debug code in the context of the Salesforce org where it will be deployed by running these tests directly from the IDE. Developers can use this feature to set breakpoints, step through code, and inspect variables without leaving the IDE interface.

You can debug in Visual Studio Code, which is the most popular option. Salesforce recommends using Visual Studio Code in conjunction with the Salesforce Extension Pack. This extension pack is a collection of Visual Studio Code extensions that provide a set of features for developing Salesforce applications, including LWC. A Lightning Web Components extension is included in the extension pack, allowing developers to debug LWC code directly from the VS Code editor.

Summary

To summarize, debugging Lightning Web Components (LWC) is a critical step in the development process. Developers can streamline the development and maintenance process by using these debugging tools and best practices, simplifying the task of debugging LWC and ensuring that their code is secure and optimized for performance.