Debugging ReactJS using IntelliJ

Debugging is an important part of the development process, and having the right tools can make a big difference in your efficiency and productivity. If you are using IntelliJ IDEA as your development environment for a ReactJS application, you can use the built-in debugger to track down and fix issues more easily. In this article, we will walk through the steps of configuring IntelliJ IDEA for debugging a ReactJS application.

Setting up the Debugger

To start, open your ReactJS project in IntelliJ IDEA and navigate to the “Run” menu. From there, select “Edit Configurations…” to open the Run/Debug Configurations window.
In this window, click the “+” button in the top left corner and select “JavaScript Debug” from the dropdown menu. This will create a new debug configuration for your ReactJS application.
Next, you will need to specify the URL of your application. If you are running your application locally, you can enter “http://localhost:3000” (assuming that your application is running on port 3000). If you are running your application on a different port or on a remote server, you will need to enter the appropriate URL.

Configuring the Breakpoints

Once you have set up the debugger, you can start adding breakpoints to your code. To do this, simply click on the left side of the editor window next to the line of code where you want to set a breakpoint. This will cause the debugger to pause execution at that line when it is reached during runtime.

You can also set conditional breakpoints, which will only pause execution if a certain condition is met. To do this, right-click on the breakpoint and select “Edit Breakpoint…” from the context menu. In the “Condition” field, enter the condition that must be met for the breakpoint to be triggered.

Debugging the Application

With your debug configuration set up and your breakpoints in place, you are now ready to start debugging your application. To do this, simply click the green “Debug” button in the top right corner of the editor window. This will launch your application in debug mode, and the debugger will pause execution at the first breakpoint it encounters.

From here, you can use the debugger controls to step through your code, inspect variables, and evaluate expressions. You can also use the “Evaluate Expression” dialog to execute code snippets and see the results in real-time.

Troubleshooting

If you are having trouble getting the debugger to work, there are a few things you can try. First, make sure that you have the latest version of IntelliJ IDEA and that you have the JavaScript Debug plugin installed.

You may also need to enable debugging in your browser. In Google Chrome, you can do this by going to the “Settings” menu and selecting “More tools” > “Developer tools.” From there, click the “Settings” icon (the gear icon) and check the “ Allow debugging” option.

If you are still having trouble, you can try running your application in a different browser or using a different debugger plugin, such as the Chrome DevTools debugger.

Special Hint

If you are running an application created using the package create-react-app, once you run npm start at the console will be printed the url where you application is running, now holding ctrl+shift click in the url link, it will automatically configure and run the debugger.

Conclusion

In conclusion, debugging a ReactJS application in IntelliJ IDEA is a straightforward process that can save you time and effort in the development process. By setting up the debugger, configuring breakpoints, and using the debugger controls, you can easily track down and fix issues in your code.