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How To Set Up Nextjs Debugger To Debug Your Applications

Are you struggling to track down bugs in your Next.js applications on Vercel? Find out how Vercel logging tool can help you identify issues that are common to Next.js apps. This blog will provide valuable insights into the Next.js debugger, guiding you through effective debugging strategies.

Next.js debugger from Alerty simplifies debugging for Next.js apps, ensuring a user-friendly experience that lets you quickly achieve your debugging goals.

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Table of Contents

What is Nextjs?

man working on web app - NextJS Debugger

Next.js is an open-source web development framework created by the private company Vercel. It offers React-based web applications with server-side rendering and static website generation. React documentation recommends Next.js among recommended toolchains, advising developers to use it when building a server-rendered website with Node.js.

Server-Side Rendering in Next.js

In contrast to traditional React apps, which render their content in the client-side browser, Next.js extends this functionality to include applications rendered on the server side. Vercel holds the copyright and trademarks for Next.js and also maintains and leads its open-source development.

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Basics of Debugging in Nextjs

a blank book - NextJS Debugger

Debugging in Next.js involves finding and fixing issues in your code to ensure your application runs smoothly. It’s akin to being a detective, where you trace clues to solve the mystery of errors that may occur. Setting breakpoints is crucial in debugging Next.js applications as it allows you to inspect variables and step through the code to identify and fix bugs effectively.

Identifying Errors in Client-Side and Server-Side Code

Understanding common error messages and knowing where to look for problems in both server-side and client-side code are essential skills for debugging in Next.js. This knowledge will equip you to handle any issues that may arise and streamline the debugging process.

Honing Your Debugging Skills in Next.js

While debugging may seem challenging initially, practice and patience are crucial to improving your ability to spot and rectify bugs effectively. Stay curious and persistent in your code to become proficient at debugging in Next.js.

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Setting Up Nextjs Debugger

coding screen for issues - NextJS Debugger

Debugging With Visual Studio Code

Visual Studio Code (VSCode) is a popular code editor with powerful built-in debugging capabilities. 

To debug your Next.js application in VSCode, follow these steps:

1. Install the "Debugger for Chrome" extension from the VSCode marketplace if you haven't alread done so.

  1. Create a `.vscode/launch.json` file in the root of your project if it doesn't already exist, and add the following configuration:

    json
    {
    "version": "0.2.0",
    "configurations": [
        {
          "type": "chrome",
          "request": "launch",
          "name": "Launch Chrome",
          "url": "http://localhost:3000",
          "webRoot": "${workspaceFolder}"
        }
      ]
    }
  2. Start your Next.js application in development mode: `npm run dev` or `yarn dev`.

  3. In VSCode, open the "Run" panel and click the "Run" button (the green play icon) next to the "Launch Chrome" configuration.

Debugging With Chrome DevTools

Client-side code:

- Start your development server as usual by running `next dev`, `npm run dev`, or `yarn dev`.
- Open Chrome's Developer Tools and go to the Sources tab.

Server-side code:

- To debug server-side Next.js code with Chrome DevTools, pass the `--inspect` flag to the underlying Node.js process:

`bash
NODE_OPTIONS='--inspect' next dev

Debugging on Windows

Windows users may encounter an issue when using `NODE_OPTIONS='--inspect'`. To get around this, install the `cross-env` package as a development dependency and replace the dev script with the following:

json
{
  "scripts": {
    "dev": "cross-env NODE_OPTIONS='--inspect' next dev"
  }
}

Ensure Windows Defender is disabled, as it may affect Next.js development.

Following these steps, you can set up an effective debugging environment for your Next.js applications. Debugging is essential to the development process and allows you to efficiently identify and fix issues in your code. Whether you prefer using Visual Studio Code or Chrome DevTools, Next.js provides various options for debugging your applications without interruption.

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Other Nextjs Debugging Techniques

man being focused on NextJS Debugger

Using Console Logs

A straightforward method to debug your application is by using console.log statements. This technique helps you inspect values and follow the flow of your application. For example:

function HomePage() {

  console.log("HomePage component loaded");

  return <div>Welcome to the HomePage!</div>;

}

 

export default HomePage;

Using Debugger Statement

You can use the debugger statement in your code to pause execution and inspect the current state directly in the browser's DevTools or VS Code:

function HomePage() {

  debugger; // Execution will pause here

  return <div>Welcome to the HomePage!</div>;

}

 

export default HomePage;

Using React Developer Tools

The React Developer Tools extension for Chrome and Firefox allows you to inspect the React component hierarchy, props, state, and more:

Inspect Components

Navigate through the component tree to see each component's current state and props.

Performance Profiler

Analyze the performance of your React components to identify slow renders.

Highlight Updates

See which components are re-rendering in real-time to detect unnecessary re-renders.

Error Boundaries

Error boundaries in React components can help catch and handle errors in the component tree gracefully:

class ErrorBoundary extends React.Component {

  constructor(props) {

    super(props);

    this.state = { hasError: false };

  }

 

  static getDerivedStateFromError(error) {

    return { hasError: true };

  }

 

  componentDidCatch(error, errorInfo) {

    // Log error to an error reporting service

    console.error("ErrorBoundary caught an error", error, errorInfo);

  }

 

  render() {

    if (this.state.hasError) {

      return <h1>Something went wrong.</h1>;

    }

    return this.props.children;

  }

}

 

export default ErrorBoundary;

Use Error Boundaries to catch errors in specific application parts and display fallback UI.

Using Next.js Built-in Error Page

Next.js provides a built-in error page to handle errors gracefully. You can customize this page to log errors and provide useful information to users:

// pages/_error.js

import React from 'react';

 

function Error({ statusCode }) {

  return (

    <p>

      {statusCode

        ? `An error ${statusCode} occurred on server`

        : 'An error occurred on client'}

    </p>

  );

}

 

Error.getInitialProps = ({ res, err }) => {

  const statusCode = res ? res.statusCode : err ? err.statusCode : 404;

  return { statusCode };

};

 

export default Error;

Source Maps for Client-Side Code

For easier debugging of minified production code, ensure that source maps are generated and accessible. Source maps allow you to map minified code back to the source:

javascript

Copy code

// next.config.js

module.exports = {

  webpack(config, { dev }) {

    if (!dev) {

      config.devtool = 'source-map';

    }

    return config;

  },

};

Logging Middleware

Create middleware to log requests and responses. This can help you debug issues by inspecting the data being sent to and from your server:

// middleware/logger.js

export default function logger(req, res, next) {

  console.log(`${req.method} ${req.url}`);

  next();

}

 

// Apply middleware in your server.js or next.config.js

const express = require('express');

const next = require('next');

const logger = require('./middleware/logger');

 

const dev = process.env.NODE_ENV !== 'production';

const app = next({ dev });

const handle = app.getRequestHandler();

 

app.prepare().then(() => {

  const server = express();

  server.use(logger);

 

  server.all('*', (req, res) => {

    return handle(req, res);

  });

 

  server.listen(3000, (err) => {

    if (err) throw err;

    console.log('> Ready on http://localhost:3000');

  });

});

Using External Logging Services

Integrate external logging services to get advanced error tracking and performance monitoring like:

  • Alerty
  • LogRocket
  • Sentry
  • New Relic 

Optimize Your Development Workflow With Powerful Cloud Monitoring

Alerty is a cloud monitoring service designed specifically for developers and early-stage startups. This powerful tool offers various monitoring services, including:

  • Application performance monitoring,
  • Database monitoring
  • Incident management

Alerty supports various technologies commonly used by developers, such as:

  • NextJS
  • React
  • Vue
  • Node.js

By leveraging Alerty, developers can quickly identify and resolve application issues, ensuring optimal end-user performance. 

One of Alerty's standout features is its support for monitoring key metrics in popular databases like:

  • Supabase
  • PostgreSQL
  • RDS

By tracking metrics such as CPU usage and memory consumption, Alerty provides deep insights into database performance, enabling developers to optimize their database operations effectively.

Proactive User Experience

Alerty excels in incident management and Real-User Monitoring (RUM). This combination of services allows developers to proactively address issues before they impact end-users, ensuring a seamless user experience. Alerty's Universal Service Monitoring feature covers essential dependencies like:

  • Stripe API
  • OpenAI
  • Vercel

Cost-Effective AI Monitoring

Alerty uses AI to simplify setup, providing a cost-effective solution compared to competitors. It is designed for ease of use, allowing quick setup, and integrates with tools like Sentry, making it ideal for developers and small teams needing efficient, affordable monitoring. 

Catch issues before they affect your users with Alerty's Nextjs logging tool today!

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Common Issues While Debugging Nextjs Applications

person finding issues with NextJS Debugger

Debugging Next.js apps is hard. It often leads to common issues that developers face. One common problem is dealing with asynchronous code. Breakpoints may not hit when wanted due to timing issues. This can make it tricky to pinpoint the source of bugs.

Leverage GitHub Issues for Next.js Debugging

If you face issues debugging your Next.js app, check its GitHub repository. Look for open topics. They are about debugging async code or breakpoints in Next.js. Reviewing and adding to open issues on GitHub can provide valuable insights. They may have workarounds or fixes from the community. These can help you overcome these challenges better.

Mastering Server-Side Debugging

Ensuring that server-side code executes correctly and handling errors effectively requires careful attention and troubleshooting. One way to address this is by utilizing environment variables. For example, you can use NODE_OPTIONS to add options for Node.js, which can aid in debugging and optimizing server-side code.

Running commands like npm run dev can start the development server and monitor its output for any issues during development. These practices help streamline the debugging process and ensure smooth execution of debugging server-side code.

Enhancing Debugging Workflow

This includes tasks such as running commands. For example, running yarn dev starts the development server. It also monitors its output for issues during development. Running yarn dev starts the Next.js development server. It compiles code, bundles assets, and serves the app. This lets developers preview and test their Next.js apps. They do this in a development environment before deploying to production.

Understanding Client-Side Debugging Challenges

Debugging code on the client side within the Next.js framework presents its challenges. Understanding how data flows between different components and tracking state changes can be challenging, especially when diagnosing and resolving bugs quickly.

Tools for Efficient Debugging

Setting up the debugging environment in VS Code may have configuration challenges, which can cause delays in issue resolution. Tools like the VS Code inspector, which offers a visual interface, can make debugging easier.

Optimizing the VS Code Inspector for Effective Debugging Sessions

The VS Code inspector has a user-friendly interface. It is used to set up and manage debug sessions. Developers diagnose and fix issues in their codebase with the help of features like:

  • Breakpoint management
  • Variable inspection
  • Call stack navigation help

It’s crucial to configure settings for optimal performance during debugging sessions. This includes making sure the debugging UI is easy to use. It provides developers with quick access to key debugging features. It also gives them controls to analyze and fix code.

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Optimizing Debugging With Advanced VS Code Features

woman helping with NextJS Debugger

Using advanced features in Visual Studio Code can help optimize debugging for your Next.js apps. Front-end debugging tools, like VS Code breakpoints, can streamline debugging, leading to faster issue resolution and better code.

One key feature is the ability to set conditional breakpoints. You can pause the code only when you meet specific conditions. This can simplify your debugging. It focuses on crucial code areas.

Utilizing the VS Code Watch Window During Debugging

Another powerful tool is the watch window in VS Code. It lets you track variables and expressions in real time as you debug. This feature provides valuable insights into your application. It does so at different points during execution.

Leverage the Integrated VS Code Terminal

Using the terminal in VS Code helps you enter debug mode and interact with your Next.js project during debugging. It removes the need to switch between tools, streamlining your development process and allowing for seamless debugging directly within your coding environment.

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Catch Issues Before They Affect Your Users with Alerty's Nextjs Logging Tool

Alerty is a robust cloud monitoring service tailored to developers and startups in their early stages. Offering a broad spectrum of monitoring features, Alerty aims to provide a comprehensive solution to address various aspects of application performance. One of the vital focal points of Alerty is its Next.js logging tool, which allows developers to track, monitor, and manage logs efficiently. This tool ensures the seamless operation of applications and websites built with Next.js.

The Pillar of Alerty's Next.js Logging Tool

One of the standout features of Alerty's offerings is its application performance monitoring capabilities. By providing real-time insights into critical performance metrics, Alerty enables developers to identify and address potential issues promptly. This aspect is crucial in maintaining the optimal performance of websites and applications, ensuring a smooth user experience.

Core Component of Alerty's Next.js Logging Tool

In addition to application performance monitoring, Alerty also offers robust database monitoring capabilities. Alerty gives developers a holistic view of their database performance by tracking key metrics such as CPU usage and memory consumption. This functionality is essential in detecting and resolving issues that may arise within the database layer, contributing to the application's overall stability.

Ensuring Seamless Operation with Alerty's Next.js Logging Tool

Incident management is critical to any monitoring solution, and Alerty excels in this area. With quick incident management features, developers can promptly respond to critical issues and minimize downtime. This proactive approach to incident management is essential in maintaining the availability and reliability of applications built with Next.js.

Optimizing User Experience with Alerty's Next.js Logging Tool

Alerty offers real user monitoring (RUM), a valuable feature that enables developers to gain insights into user behavior and experience. By monitoring user interactions in real time, developers can identify areas for improvement and optimize the user experience. This functionality is vital in ensuring that applications built with Next.js meet user expectations and deliver a seamless experience.

Extending Monitoring Capabilities With Alerty's Next.js Logging Tool

Alerty's Universal Service Monitoring feature allows developers to monitor dependencies beyond their application stack. By covering essential services and APIs like Stripe, OpenAI, and Vercel, developers can ensure the availability and performance of these critical dependencies. This capability benefits developers working with Next.js, as it provides a comprehensive view of their application ecosystem.

Alerty's Next.js Logging Tool - A Powerful Solution for Developers

Alerty offers a monitoring solution tailored to developers working with technologies like Next.js.  

It provides a comprehensive solution to address various aspects of application performance with features like: 

  • Application performance monitoring
  • Database monitoring
  • Incident management
  • RUM
  • Universal service monitoring 

By leveraging Alerty's Next.js logging tool, developers can gain real-time insights into critical metrics, identify and resolve issues promptly, and optimize the overall user experience. 

Today, catch problems before they affect your users with Alerty's Next.js logging tool!

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