Use InitiateAuth with an Amazon SDK or CLI - Amazon Cognito
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Use InitiateAuth with an Amazon SDK or CLI

The following code examples show how to use InitiateAuth.

Action examples are code excerpts from larger programs and must be run in context. You can see this action in context in the following code examples:

.NET
Amazon SDK for .NET
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

/// <summary> /// Initiate authorization. /// </summary> /// <param name="clientId">The client Id of the application.</param> /// <param name="userName">The name of the user who is authenticating.</param> /// <param name="password">The password for the user who is authenticating.</param> /// <returns>The response from the initiate auth request.</returns> public async Task<InitiateAuthResponse> InitiateAuthAsync(string clientId, string userName, string password) { var authParameters = new Dictionary<string, string>(); authParameters.Add("USERNAME", userName); authParameters.Add("PASSWORD", password); var authRequest = new InitiateAuthRequest { ClientId = clientId, AuthParameters = authParameters, AuthFlow = AuthFlowType.USER_PASSWORD_AUTH, }; var response = await _cognitoService.InitiateAuthAsync(authRequest); Console.WriteLine($"Result Challenge is : {response.ChallengeName}"); return response; }
  • For API details, see InitiateAuth in Amazon SDK for .NET API Reference.

Go
SDK for Go V2
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

type CognitoActions struct { CognitoClient *cognitoidentityprovider.Client } // SignIn signs in a user to Amazon Cognito using a username and password authentication flow. func (actor CognitoActions) SignIn(clientId string, userName string, password string) (*types.AuthenticationResultType, error) { var authResult *types.AuthenticationResultType output, err := actor.CognitoClient.InitiateAuth(context.TODO(), &cognitoidentityprovider.InitiateAuthInput{ AuthFlow: "USER_PASSWORD_AUTH", ClientId: aws.String(clientId), AuthParameters: map[string]string{"USERNAME": userName, "PASSWORD": password}, }) if err != nil { var resetRequired *types.PasswordResetRequiredException if errors.As(err, &resetRequired) { log.Println(*resetRequired.Message) } else { log.Printf("Couldn't sign in user %v. Here's why: %v\n", userName, err) } } else { authResult = output.AuthenticationResult } return authResult, err }
  • For API details, see InitiateAuth in Amazon SDK for Go API Reference.

JavaScript
SDK for JavaScript (v3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

const initiateAuth = ({ username, password, clientId }) => { const client = new CognitoIdentityProviderClient({}); const command = new InitiateAuthCommand({ AuthFlow: AuthFlowType.USER_PASSWORD_AUTH, AuthParameters: { USERNAME: username, PASSWORD: password, }, ClientId: clientId, }); return client.send(command); };
  • For API details, see InitiateAuth in Amazon SDK for JavaScript API Reference.

Python
SDK for Python (Boto3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

This example shows you how to start authentication with a tracked device. To complete sign-in, the client must respond correctly to Secure Remote Password (SRP) challenges.

class CognitoIdentityProviderWrapper: """Encapsulates Amazon Cognito actions""" def __init__(self, cognito_idp_client, user_pool_id, client_id, client_secret=None): """ :param cognito_idp_client: A Boto3 Amazon Cognito Identity Provider client. :param user_pool_id: The ID of an existing Amazon Cognito user pool. :param client_id: The ID of a client application registered with the user pool. :param client_secret: The client secret, if the client has a secret. """ self.cognito_idp_client = cognito_idp_client self.user_pool_id = user_pool_id self.client_id = client_id self.client_secret = client_secret def sign_in_with_tracked_device( self, user_name, password, device_key, device_group_key, device_password, aws_srp, ): """ Signs in to Amazon Cognito as a user who has a tracked device. Signing in with a tracked device lets a user sign in without entering a new MFA code. Signing in with a tracked device requires that the client respond to the SRP protocol. The scenario associated with this example uses the warrant package to help with SRP calculations. For more information on SRP, see https://en.wikipedia.org/wiki/Secure_Remote_Password_protocol. :param user_name: The user that is associated with the device. :param password: The user's password. :param device_key: The key of a tracked device. :param device_group_key: The group key of a tracked device. :param device_password: The password that is associated with the device. :param aws_srp: A class that helps with SRP calculations. The scenario associated with this example uses the warrant package. :return: The result of the authentication. When successful, this contains an access token for the user. """ try: srp_helper = aws_srp.AWSSRP( username=user_name, password=device_password, pool_id="_", client_id=self.client_id, client_secret=None, client=self.cognito_idp_client, ) response_init = self.cognito_idp_client.initiate_auth( ClientId=self.client_id, AuthFlow="USER_PASSWORD_AUTH", AuthParameters={ "USERNAME": user_name, "PASSWORD": password, "DEVICE_KEY": device_key, }, ) if response_init["ChallengeName"] != "DEVICE_SRP_AUTH": raise RuntimeError( f"Expected DEVICE_SRP_AUTH challenge but got {response_init['ChallengeName']}." ) auth_params = srp_helper.get_auth_params() auth_params["DEVICE_KEY"] = device_key response_auth = self.cognito_idp_client.respond_to_auth_challenge( ClientId=self.client_id, ChallengeName="DEVICE_SRP_AUTH", ChallengeResponses=auth_params, ) if response_auth["ChallengeName"] != "DEVICE_PASSWORD_VERIFIER": raise RuntimeError( f"Expected DEVICE_PASSWORD_VERIFIER challenge but got " f"{response_init['ChallengeName']}." ) challenge_params = response_auth["ChallengeParameters"] challenge_params["USER_ID_FOR_SRP"] = device_group_key + device_key cr = srp_helper.process_challenge(challenge_params, {"USERNAME": user_name}) cr["USERNAME"] = user_name cr["DEVICE_KEY"] = device_key response_verifier = self.cognito_idp_client.respond_to_auth_challenge( ClientId=self.client_id, ChallengeName="DEVICE_PASSWORD_VERIFIER", ChallengeResponses=cr, ) auth_tokens = response_verifier["AuthenticationResult"] except ClientError as err: logger.error( "Couldn't start client sign in for %s. Here's why: %s: %s", user_name, err.response["Error"]["Code"], err.response["Error"]["Message"], ) raise else: return auth_tokens
  • For API details, see InitiateAuth in Amazon SDK for Python (Boto3) API Reference.

For a complete list of Amazon SDK developer guides and code examples, see Using this service with an Amazon SDK. This topic also includes information about getting started and details about previous SDK versions.