Authentication

Create users, log in with Auth Key or Auth Token, check login status, and log out using the CometChat JavaScript SDK.

AI Integration Quick Reference

// Check existing session
const user = await CometChat.getLoggedinUser();

// Login with Auth Key (development only)
CometChat.login("cometchat-uid-1", "AUTH_KEY").then(user => console.log("Logged in:", user));

// Login with Auth Token (production)
CometChat.login("AUTH_TOKEN").then(user => console.log("Logged in:", user));

// Logout
CometChat.logout().then(() => console.log("Logged out"));

Create users via: Dashboard (testing) | REST API (production) Test UIDs: cometchat-uid-1 through cometchat-uid-5

Create User

Before you log in a user, you must add the user to CometChat.

1. For proof of concept/MVPs: Create the user using the CometChat Dashboard.
2. For production apps: Use the CometChat Create User API to create the user when your user signs up in your app.

Authentication Flow

We have set up 5 users for testing having UIDs: cometchat-uid-1, cometchat-uid-2, cometchat-uid-3, cometchat-uid-4 and cometchat-uid-5.

Once initialization is successful, you will need to log the user into CometChat using the login() method.

We recommend you call the CometChat login method once your user logs into your app. The login() method needs to be called only once.

The CometChat SDK maintains the session of the logged-in user within the SDK. Thus you do not need to call the login method for every session. You can use the CometChat.getLoggedinUser() method to check if there is any existing session in the SDK. This method should return the details of the logged-in user. If this method returns null, it implies there is no session present within the SDK and you need to log the user into CometChat.

Login using Auth Key

This straightforward authentication method is ideal for proof-of-concept (POC) development or during the early stages of application development. For production environments, however, we strongly recommend using an AuthToken instead of an Auth Key to ensure enhanced security.

Auth Key is for development/testing only. In production, generate Auth Tokens on your server using the REST API and pass them to the client. Never expose Auth Keys in production client code.

TypeScript

const UID: string = "cometchat-uid-1";
const authKey: string = "AUTH_KEY";

CometChat.getLoggedinUser().then(
  (user: CometChat.User) => {
    if (!user) {
      CometChat.login(UID, authKey).then(
        (user: CometChat.User) => {
          console.log("Login Successful:", { user });
        },
        (error: CometChat.CometChatException) => {
          console.log("Login failed with exception:", { error });
        }
      );
    }
  },
  (error: CometChat.CometChatException) => {
    console.log("Some Error Occurred", { error });
  }
);

JavaScript

const UID = "cometchat-uid-1";
const authKey = "AUTH_KEY";

CometChat.getLoggedinUser().then(
  (user) => {
    if (!user) {
      CometChat.login(UID, authKey).then(
        (user) => {
          console.log("Login Successful:", { user });
        },
        (error) => {
          console.log("Login failed with exception:", { error });
        }
      );
    }
  },
  (error) => {
    console.log("Some Error Occurred", { error });
  }
);

Async/Await

const UID = "cometchat-uid-1";
const authKey = "AUTH_KEY";

try {
  const loggedInUser = await CometChat.getLoggedinUser();
  if (!loggedInUser) {
    const user = await CometChat.login(UID, authKey);
    console.log("Login Successful:", { user });
  }
} catch (error) {
  console.log("Login failed with exception:", { error });
}

Parameters	Description
UID	The UID of the user that you would like to login
authKey	CometChat Auth Key

After the user logs in, their information is returned in the User object on Promise resolved.

Login using Auth Token

This advanced authentication procedure does not use the Auth Key directly in your client code thus ensuring safety.

1. Create a User via the CometChat API when the user signs up in your app.
2. Create an Auth Token via the CometChat API for the new user and save the token in your database.
3. Load the Auth Token in your client and pass it to the login() method.

TypeScript

const authToken: string = "AUTH_TOKEN";

CometChat.getLoggedinUser().then(
  (user: CometChat.User) => {
    if (!user) {
      CometChat.login(authToken).then(
        (user: CometChat.User) => {
          console.log("Login Successful:", { user });
        },
        (error: CometChat.CometChatException) => {
          console.log("Login failed with exception:", { error });
        }
      );
    }
  },
  (error: CometChat.CometChatException) => {
    console.log("Some Error Occurred", { error });
  }
);

JavaScript

const authToken = "AUTH_TOKEN";

CometChat.getLoggedinUser().then(
  (user) => {
    if (!user) {
      CometChat.login(authToken).then(
        (user) => {
          console.log("Login Successful:", { user });
        },
        (error) => {
          console.log("Login failed with exception:", { error });
        }
      );
    }
  },
  (error) => {
    console.log("Some Error Occurred", { error });
  }
);

Async/Await

const authToken = "AUTH_TOKEN";

try {
  const loggedInUser = await CometChat.getLoggedinUser();
  if (!loggedInUser) {
    const user = await CometChat.login(authToken);
    console.log("Login Successful:", { user });
  }
} catch (error) {
  console.log("Login failed with exception:", { error });
}

Parameter	Description
authToken	Auth Token of the user you would like to login

After the user logs in, their information is returned in the User object on the Promise resolved.

Logout

You can use the logout() method to log out the user from CometChat. We suggest you call this method once your user has been successfully logged out from your app.

TypeScript

CometChat.logout().then(
  (loggedOut: Object) => {
    console.log("Logout completed successfully");
  },
  (error: CometChat.CometChatException) => {
    console.log("Logout failed with exception:", { error });
  }
);

JavaScript

CometChat.logout().then(
  () => {
    console.log("Logout completed successfully");
  },
  (error) => {
    console.log("Logout failed with exception:", { error });
  }
);

Async/Await

try {
  await CometChat.logout();
  console.log("Logout completed successfully");
} catch (error) {
  console.log("Logout failed with exception:", { error });
}

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Login Listener

The CometChat SDK provides real-time updates for login and logout events via the LoginListener class.

Delegate Method	Description
loginSuccess(event)	User logged in successfully. Provides the User object.
loginFailure(event)	Login failed. Provides a CometChatException.
logoutSuccess()	User logged out successfully.
logoutFailure(event)	Logout failed. Provides a CometChatException.

Add Login Listener

TypeScript

const listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.addLoginListener(
    listenerID,
    new CometChat.LoginListener({
        loginSuccess: (user: CometChat.User) => {
            console.log("LoginListener :: loginSuccess", user);
        },
        loginFailure: (error: CometChat.CometChatException) => {
            console.log("LoginListener :: loginFailure", error);
        },
        logoutSuccess: () => {
            console.log("LoginListener :: logoutSuccess");
        },
        logoutFailure: (error: CometChat.CometChatException) => {
            console.log("LoginListener :: logoutFailure", error);
        }
    })
);

JavaScript

let listenerID = "UNIQUE_LISTENER_ID";
CometChat.addLoginListener(
    listenerID,
    new CometChat.LoginListener({
        loginSuccess: (e) => {
            console.log("LoginListener :: loginSuccess", e);
        },
        loginFailure: (e) => {
            console.log("LoginListener :: loginFailure", e);
        },
        logoutSuccess: () => {
            console.log("LoginListener :: logoutSuccess");
        },
        logoutFailure: (e) => {
            console.log("LoginListener :: logoutFailure", e);
        }
    })
);

Remove Login Listener

TypeScript

const listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeLoginListener(listenerID);

JavaScript

const listenerID = "UNIQUE_LISTENER_ID";
CometChat.removeLoginListener(listenerID);

Always remove login listeners when they’re no longer needed (e.g., on component unmount or page navigation). Failing to remove listeners can cause memory leaks and duplicate event handling.

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Next Steps

Send Messages

Send your first text, media, or custom message

User Management

Create, update, and delete users programmatically

Connection Status

Monitor the SDK connection state in real time

All Real-Time Listeners

Complete reference for all SDK event listeners