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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.
Sample UsersWe have setup 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 ComeChat.

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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. 
var UID = "UID";
var 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("Something went wrong", error);
  }
);
ParametersDescription
UIDThe UID of the user that you would like to login
authKeyCometChat Auth Key
After the user logs in, their information is returned in the User object on Promise resolved.

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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.
var 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("Something went wrong", error);
  }
);
ParameterDescription
authTokenAuth 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.

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