Building a Complete React Chat App with CometChat UI kit

Building chat apps in React from scratch is an ambitious task that comes with a range of complex challenges, such as

CometChat’s UI Kit simplifies the development process with pre-built, customizable React chat components that remove the need for heavy lifting. These components come with beautifully designed UI elements with perfect theming, robust functionality, and integrated backend logic, providing ready-to-use features right out of the box.

With an intuitive design and all the essential elements needed to create a seamless chat experience readily available, you’ll spend minimal time on customization.

To get an even quicker start, check out this video showcasing how to use CometChat’s Visual Builder to effortlessly integrate chat into your react application.

The Visual Builder is a low-code chat builder built on top of our React Chat UI Kit. It lets you quickly launch a fully functional chat experience. Customize the UI to match your app’s theme, choose and configure the features you need, and preview the experience in real time.

Once you're satisfied, simply download the working React code and drop it directly into your application.

To better understand how CometChat can accelerate your development process, here’s a quick comparison of building a chat app using the traditional DIY approach versus leveraging CometChat.

In this tutorial, we'll build a full-featured chat application that supports:

Prerequisites

1. Set up your development environment

First, create a new React application by running:

This command does two things:

Now, install the CometChat dependencies by adding the React chat UI Kit.

This command installs CometChat's React UI Kit, which includes:

Note: Make sure you have Node.js and npm installed on your system before running these commands.

2. Create a CometChat account

In order to use the components present in the UI kit, you need a CometChat account. Sign up for a CometChat account from here. After signing up, create a new app in your dashboard and copy these required credentials from your app:

You'll use these credentials in the following steps to initialize the CometChat UI Kit and configure your application.

3. Initialize the React chat UI kit

In this step, we will initialize the CometChatUIKit within the React application using the credentials obtained from your CometChat app. If the initialization is successful, a success message will be logged to the console. If there's an error (e.g., due to invalid credentials or network issues), an error message is logged instead.

With the CometChatUIKit initialized, we can now start building the core components of our chat application. We'll start by setting up user authentication, including login functionality and session management, to ensure secure access and maintain user state throughout the application.

Next, we’ll build the main chat interface, which includes designing the primary chat layout, setting up the message display area, and implementing real-time message exchange. The chat interface will serve as the central hub for users to view their conversations and intercat with other users in real time.

1. User login and authentication flow

Before diving into building the chat interface, we'll create a login component that authenticates users with CometChat using their unique User ID. This authentication system is fundamental as it establishes a secure connection between users and CometChat servers, managing user sessions and ensuring proper access to conversations.

We'll create a login form that:

2. Building the chat interface

After implementing user authentication, the next step is to create the main chat interface where users can exchange messages. This section demonstrates how to seamlessly integrate the chat interface into your React app.

If chat is a separate feature in your app, this interface will serve as the inbox. However, for apps like WhatsApp or Telegram, where messaging is the primary focus, this will function as the homepage of your app, where users land after logging in.

The chat interface we're building will consist of two main elements:

To simplify the development process, we’ll use the CometChatConversationsWithMessages component from the CometChat React UI Kit. This component offers developers a streamlined way to build a complete chat interface packed with all user engagement features with a single import.

It comes pre-configured with all the UI elements and features needed for a fully functional chat interface. Additionally, it connects directly to CometChat's backend infrastructure, managing all server communications and real-time updates.

By using this one component, you eliminate the need to configure features separately, import individual UI elements manually and set up custom server interactions for chat functionalities.

For Implementing the chat interface, update your App.js with the following code. This code establishes the core logic for rendering our chat interface.

The implementation follows these steps:

When the component mounts, it first checks the user's authentication status using the useEffect hook. Then, it retrieves the logged-in user's information through the CometChat SDK to verify their active session.

Based on this authentication check, it makes one of two decisions:

This authentication flow ensures that only verified users can access the chat functionality. Once implemented successfully, the chat screen will display the conversation list and message screen, allowing users to send and receive messages in real-time.

In the next steps, we will show you how to

When you implement CometChatConversationsWithMessages, you're getting a robust set of real-time chat features that would typically take months to build from scratch. This includes

1. Real-time message delivery

2. Message history and syncing

3. Presence system

4. Typing indicators and read Receipts

Beyond the UI: How CometChat handles complex chat operations

In addition to the features mentioned above, CometChat handles all the complex and resource-intensive operations needed to run and manage chat in your React app. Here are some critical backend activities that CometChat manages behind the scenes:

Building these features independently would require significant expertise, time, and resources. By handling all these complex operations, CometChat frees you from having to worry about:

• Setting up and maintaining WebSocket servers (which can cost thousands in infrastructure)

• Implementing reliable message delivery guarantees across unstable networks

• Managing presence servers for real-time user status updates

• Creating sophisticated typing indicator throttling to prevent server overload

• Developing robust message storage and retrieval systems that can handle millions of messages

• Building complex network handling logic for various edge cases and reconnection scenarios

Now that we have our basic chat functionality working, let's look at how to add powerful features to make your cha app stand out. Each of these features requires only minimal code but adds significant value to your chat application.

1. Message threads

Enable threaded conversations similar to Slack or Microsoft Teams:

2. Message reactions

Allow users to react to messages with emojis:

3. User Mentions

Implement @mentions to tag users in conversations:

4. Rich Media Messages

Enable sharing of various media types:

5. Link Previews

Automatically generate rich previews for shared links:

1. Setting up notifications

Now that your chat functionality is up and running, it's time to enable notifications so users never miss a message. CometChat’s Notifications module allows you to set up and manage notifications across multiple providers directly from the dashboard, ensuring centralized control and effortless configuration. You can easily integrate push notifications with APNs and FCM, email notifications with SendGrid, and SMS alerts with Twilio, or use webhooks to connect with any provider of your choice.

You can also enable notification preferences for your users, allowing them to customize when and how they receive notifications. Additionally, our customizable templates let you tailor notifications to your app’s tone and branding.

 2. Setting up advanced moderation

Next, let’s explore CometChat’s powerful moderation capabilities, designed to help you maintain a safe and respectful environment for your users..

Front-end moderation

• User reporting: Empower your users to report inappropriate behavior or content directly from the chat interface.

• User blocking: Allow users to block others, preventing unwanted interactions.

• Message flagging: Enables users to flag specific messages for review by administrators.

Moderation queue

Use our centralized moderation dashboard to give app admins an organized view of flagged messages, reported users, and blocked content. From this dashboard, admins can take real-time action on flagged content, issue user bans or warnings, and escalate issues for higher-level review, all in one place.

Proactive content moderation:

Use our advanced AI filters to prevent harmful content from entering your chat. These filters automatically screen every message exchanged in your app for violations defined by you and take action based on the moderation rules you’ve set up with our rules engine.

CometChat’s rules engine lets you create custom rules to address common moderation scenarios. You can define which filters to use for identifying violations and specify how to handle them, such as blocking a user or removing them from a group. This helps you keep your app free from:

• Spam: Block unwanted or malicious content.

• Harassment: Automatically filter harmful messages or behavior.

• Image and Video Moderation: Analyze and filter media content to ensure it follows guidelines

3. Using Webhooks to extend your chat app's functionality

Leverage our webhooks to trigger actions based on key events like message exchanges, user interactions, group changes, and call activities. You can use them to automate tasks, integrate with external services, and optimize the chat experience in your app. You can configure these webhooks directly from the CometChat dashboard.

Here’s a list of available webhooks:

1. Theme-Level Customization

CometChat makes it incredibly simple to tailor the look and feel of the UI Kit to match your app's theme. Whether it's adjusting the base colors, accent colors, or changing the typography settings, you can easily achieve this with minimal coding using the built-in theme provider. All it takes is modifying the palette and typography classes.

Defining your color scheme

The palette class allows you to customize the visual color scheme, including backgrounds, text, buttons, errors, and accents of your app. With just a few adjustments, you can:

Managing font styles

The typography class gives you full control over your app's text appearance.

2. Component customization 

Conversations component customisation

The Conversations component displays all conversations related to the currently logged-in user. To ensure the component aligns with your app's design and branding, you can easily customize its appearance by adjusting the properties exposed by the ConversationsStyle class. Below, you'll find a table outlining all the properties you can modify to tailor the component to your specific needs.

For more advanced customization, you can define custom views within the Conversations component. This allows you to fully control and tailor each element of the interface, such as layouts, views, and UI elements, ensuring that the component perfectly matches your app's overall aesthetics and functionality. .

Messages component customization 

The Messages component is a central feature of our chat interface, responsible for rendering the area where messages are exchanged between users and groups. It plays a key role in managing the real-time flow of messages within the app. Below, you'll find a table outlining all the properties you can modify to tailor the messages component to your specific needs

You have the flexibility to customize a wide range of elements beyond just themes and component styling, allowing you to create a chat experience that  fits your app’s unique requirements. 

Here are some of the key areas you can customize to achieve the exact look and feel you want for your chat interface:

Common customisation scenarios

To inspire your creativity and customization, we've compiled some common customization scenarios that our customers often use to enhance their chat applications. While CometChat's UI Kit is designed to be versatile and suitable for most use cases out-of-the-box, many users take the extra step to tailor the interface even further, ensuring it aligns with their unique brand identity. These customizations not only enhance the user experience but also help create a more engaging, personalized, and cohesive design that resonates with users.

Before you deploy your project to production, it's important to properly structure, test, and verify that everything works as expected. In this section, we'll walk you through how to run the project locally, test key features, and ensure that everything is functioning properly before moving to deployment.

The structure of your project should look like this:

This structure includes all the core components like Login, Chat, configuration files, and environment variables to manage sensitive credentials.

Testing checklist

To ensure that your chat app works flawlessly before deployment, here's a checklist of features you should test:

User authentication

Messaging features

Real-time features

Once you've tested the app locally and confirmed that all features are working correctly, it's time to build and deploy it. Here's how to proceed:

Environment Setup

Before deployment, ensure your environment is set up for a production build.

This will create an optimized build of your project, ready for deployment. You can test it locally using the serve command to simulate a production environment.

Environment Variables

Make sure that your environment variables are configured correctly for production. This includes securing sensitive credentials like API keys and authentication tokens.

• Configure production environment variables: Ensure all keys and tokens are correctly set for production. Never expose sensitive data in your code.

• Ensure secure credential handling: Make use of .env files or a secrets management system to keep production credentials secure.

Haris Kumar

Lead Content Strategist , CometChat

Haris brings nearly half a decade of expertise in B2B SaaS content marketing, where he excels at developing strategic content that drives engagement and supports business growth. His deep understanding of the SaaS landscape allows him to craft compelling narratives that resonate with target audiences. Outside of his professional pursuits, Haris enjoys reading, trying out new dishes and watching new movies!