Authentication

Before users can make or receive calls, they must be authenticated with the CometChat Calls SDK. This guide covers the login and logout methods.

Sample Users

CometChat provides 5 test users: cometchat-uid-1, cometchat-uid-2, cometchat-uid-3, cometchat-uid-4, and cometchat-uid-5.

Check Login Status

Before calling login(), check if a user is already logged in using getLoggedInUser(). The SDK maintains the session internally, so you only need to login once per user session.

Swift

if let loggedInUser = CometChatCalls.getLoggedInUser() {
    // User is already logged in
    print("User already logged in: \(loggedInUser.uid ?? "")")
} else {
    // No user logged in, proceed with login
}

Objective-C

CallsUser *loggedInUser = [CometChatCalls getLoggedInUser];

if (loggedInUser != nil) {
    // User is already logged in
    NSLog(@"User already logged in: %@", loggedInUser.uid);
} else {
    // No user logged in, proceed with login
}

The getLoggedInUser() method returns a CallsUser object if a user is logged in, or nil if no session exists.

Login with UID and API Key

This method is suitable for development and testing. For production apps, use Auth Token login instead.

Security Notice

Using the API Key directly in client code is not recommended for production. Use Auth Token authentication for enhanced security.

Swift

let uid = "cometchat-uid-1" // Replace with your user's UID
let apiKey = "API_KEY" // Replace with your API Key

if CometChatCalls.getLoggedInUser() == nil {
    CometChatCalls.login(UID: uid, apiKey: apiKey, onSuccess: { user in
        print("Login successful: \(user.uid ?? "")")
    }, onError: { error in
        print("Login failed: \(error.errorDescription)")
    })
} else {
    // User already logged in
}

Objective-C

NSString *uid = @"cometchat-uid-1"; // Replace with your user's UID
NSString *apiKey = @"API_KEY"; // Replace with your API Key

if ([CometChatCalls getLoggedInUser] == nil) {
    [CometChatCalls loginWithUID:uid 
                          apiKey:apiKey 
                       onSuccess:^(CallsUser * user) {
        NSLog(@"Login successful: %@", user.uid);
    } onError:^(CometChatCallException error) {
        NSLog(@"Login failed: %@", error.errorDescription);
    }];
} else {
    // User already logged in
}

Parameter	Type	Description
UID	String	The unique identifier of the user to login
apiKey	String	Your CometChat API Key
onSuccess	Closure	Closure called with CallsUser on success
onError	Closure	Closure called with error on failure

Login with Auth Token

This is the recommended authentication method for production applications. The Auth Token is generated server-side, keeping your API Key secure.

Auth Token Flow

1. User authenticates with your backend
2. Your backend calls the CometChat Create Auth Token API
3. Your backend returns the Auth Token to the client
4. Client uses the Auth Token to login

Swift

let authToken = "AUTH_TOKEN" // Token received from your backend

CometChatCalls.login(authToken: authToken, onSuccess: { user in
    print("Login successful: \(user.uid ?? "")")
}, onError: { error in
    print("Login failed: \(error.errorDescription)")
})

Objective-C

NSString *authToken = @"AUTH_TOKEN"; // Token received from your backend

[CometChatCalls loginWithAuthToken:authToken 
                         onSuccess:^(CallsUser * user) {
    NSLog(@"Login successful: %@", user.uid);
} onError:^(CometChatCallException error) {
    NSLog(@"Login failed: %@", error.errorDescription);
}];

Parameter	Type	Description
authToken	String	Auth Token generated via CometChat API
onSuccess	Closure	Closure called with CallsUser on success
onError	Closure	Closure called with error on failure

CallsUser Object

On successful login, the callback returns a CallsUser object containing user information:

Property	Type	Description
uid	String?	Unique identifier of the user
name	String?	Display name of the user
avatar	String?	URL of the user’s avatar image
status	UserStatus	User’s online status

Logout

Call logout() when the user signs out of your application. This clears the local session and disconnects from CometChat services.

Swift

CometChatCalls.logout(onSuccess: { message in
    print("Logout successful")
}, onError: { error in
    print("Logout failed: \(error.errorDescription)")
})

Objective-C

[CometChatCalls logoutOnSuccess:^(NSString * message) {
    NSLog(@"Logout successful");
} onError:^(CometChatCallException error) {
    NSLog(@"Logout failed: %@", error.errorDescription);
}];

Error Handling

Common authentication errors:

Error Code	Description
ERROR_INVALID_UID	The provided UID is empty or invalid
ERROR_UID_WITH_SPACE	The UID contains spaces (not allowed)
ERROR_API_KEY_NOT_FOUND	The API Key is missing or invalid
ERROR_BLANK_AUTHTOKEN	The Auth Token is empty
ERROR_AUTHTOKEN_WITH_SPACE	The Auth Token contains spaces