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Starts sign-in for applications with a server-side component, for example a traditional web application

Description

Starts sign-in for applications with a server-side component, for example a traditional web application. This operation specifies the authentication flow that you'd like to begin. The authentication flow that you specify must be supported in your app client configuration. For more information about authentication flows, see Authentication flows.

This action might generate an SMS text message. Starting June 1, 2021, US telecom carriers require you to register an origination phone number before you can send SMS messages to US phone numbers. If you use SMS text messages in Amazon Cognito, you must register a phone number with Amazon Pinpoint. Amazon Cognito uses the registered number automatically. Otherwise, Amazon Cognito users who must receive SMS messages might not be able to sign up, activate their accounts, or sign in.

If you have never used SMS text messages with Amazon Cognito or any other Amazon Web Services service, Amazon Simple Notification Service might place your account in the SMS sandbox. In sandbox mode , you can send messages only to verified phone numbers. After you test your app while in the sandbox environment, you can move out of the sandbox and into production. For more information, see SMS message settings for Amazon Cognito user pools in the Amazon Cognito Developer Guide.

Amazon Cognito evaluates Identity and Access Management (IAM) policies in requests for this API operation. For this operation, you must use IAM credentials to authorize requests, and you must grant yourself the corresponding IAM permission in a policy.

Learn more

Usage

cognitoidentityprovider_admin_initiate_auth(UserPoolId, ClientId,
  AuthFlow, AuthParameters, ClientMetadata, AnalyticsMetadata,
  ContextData, Session)

Arguments

  • UserPoolId

    [required] The ID of the user pool where the user wants to sign in.

  • ClientId

    [required] The ID of the app client where the user wants to sign in.

  • AuthFlow

    [required] The authentication flow that you want to initiate. Each AuthFlow has linked AuthParameters that you must submit. The following are some example flows.

    USER_AUTH

    The entry point for choice-based authentication with passwords, one-time passwords, and WebAuthn authenticators. Request a preferred authentication type or review available authentication types. From the offered authentication types, select one in a challenge response and then authenticate with that method in an additional challenge response. To activate this setting, your user pool must be in the Essentials tier or higher.

    USER_SRP_AUTH

    Username-password authentication with the Secure Remote Password (SRP) protocol. For more information, see Use SRP password verification in custom authentication flow.

    REFRESH_TOKEN_AUTH and REFRESH_TOKEN

    Receive new ID and access tokens when you pass a REFRESH_TOKEN parameter with a valid refresh token as the value. For more information, see Using the refresh token.

    CUSTOM_AUTH

    Custom authentication with Lambda triggers. For more information, see Custom authentication challenge Lambda triggers.

    ADMIN_USER_PASSWORD_AUTH

    Server-side username-password authentication with the password sent directly in the request. For more information about client-side and server-side authentication, see SDK authorization models.

  • AuthParameters

    The authentication parameters. These are inputs corresponding to the AuthFlow that you're invoking.

    The following are some authentication flows and their parameters. Add a SECRET_HASH parameter if your app client has a client secret. Add DEVICE_KEY if you want to bypass multi-factor authentication with a remembered device.

    USER_AUTH

    • USERNAME (required)
    • PREFERRED_CHALLENGE. If you don't provide a value for PREFERRED_CHALLENGE, Amazon Cognito responds with the AvailableChallenges parameter that specifies the available sign-in methods.

    • TARGET_ACR_VALUES. An optional, space-separated list of the authentication context class reference (ACR) level URIs that you want the user to reach. List the levels in priority order, from highest to lowest. Amazon Cognito attempts the highest-priority level that the user can satisfy, and falls back through the list. Amazon Cognito ignores any value that it doesn't recognize. If none of the requested values are valid, Amazon Cognito returns an error.

      Requesting step-up authentication with this parameter requires the Essentials or Plus feature plan. On a lower feature plan, AdminInitiateAuth returns a FeatureUnavailableInTierException. USERNAME is required. When you provide an ACCESS_TOKEN, you must also provide TARGET_ACR_VALUES. Amazon Cognito returns an error if you provide an ACCESS_TOKEN without TARGET_ACR_VALUES. The USERNAME that you provide must match the user that the ACCESS_TOKEN was issued for.

      For more information about step-up authentication and how Amazon Cognito handles multi-factor authentication requirements, see Step-up authentication with ACR and AMR in the Amazon Cognito Developer Guide. - MAX_AGE. An optional integer that sets the maximum number of seconds allowed since the user last authenticated. If the user's most recent authentication is older than this value, Amazon Cognito discards the authentication-methods credit from any access token that you provide and processes the request as a fresh authentication toward the target level. The access token itself remains valid.

    USER_SRP_AUTH

    • USERNAME (required)
    • SRP_A (required)

    ADMIN_USER_PASSWORD_AUTH

    • USERNAME (required)
    • PASSWORD (required)

    REFRESH_TOKEN_AUTH/REFRESH_TOKEN

    • REFRESH_TOKEN(required)

    CUSTOM_AUTH

    • USERNAME (required)
    • ChallengeName: SRP_A (when preceding custom authentication with SRP authentication)
    • SRP_A: (An SRP_A value) (when preceding custom authentication with SRP authentication)

    For more information about SECRET_HASH, see Computing secret hash values. For information about DEVICE_KEY, see Working with user devices in your user pool.

  • ClientMetadata

    A map of custom key-value pairs that you can provide as input for any custom workflows that this action triggers. You create custom workflows by assigning Lambda functions to user pool triggers.

    When Amazon Cognito invokes any of these functions, it passes a JSON payload, which the function receives as input. This payload contains a clientMetadata attribute that provides the data that you assigned to the ClientMetadata parameter in your request. In your function code, you can process the clientMetadata value to enhance your workflow for your specific needs.

    To review the Lambda trigger types that Amazon Cognito invokes at runtime with API requests, see Connecting API actions to Lambda triggers in the Amazon Cognito Developer Guide.

    The ClientMetadata value is passed as input to the functions for only the following triggers:

    • Pre signup
    • Pre authentication
    • User migration

    This request also invokes the functions for the following triggers, but doesn't pass ClientMetadata:

    • Post authentication
    • Custom message
    • Pre token generation
    • Create auth challenge
    • Define auth challenge
    • Custom email sender
    • Custom SMS sender

    When you use the ClientMetadata parameter, note that Amazon Cognito won't do the following:

    • Store the ClientMetadata value. This data is available only to Lambda triggers that are assigned to a user pool to support custom workflows. If your user pool configuration doesn't include triggers, the ClientMetadata parameter serves no purpose.
    • Validate the ClientMetadata value.
    • Encrypt the ClientMetadata value. Don't send sensitive information in this parameter.

  • AnalyticsMetadata

    Information that supports analytics outcomes with Amazon Pinpoint, including the user's endpoint ID. The endpoint ID is a destination for Amazon Pinpoint push notifications, for example a device identifier, email address, or phone number.

  • ContextData

    Contextual data about your user session like the device fingerprint, IP address, or location. Amazon Cognito threat protection evaluates the risk of an authentication event based on the context that your app generates and passes to Amazon Cognito when it makes API requests.

    For more information, see Collecting data for threat protection in applications.

  • Session

    The optional session ID from a confirm_sign_up API request. You can sign in a user directly from the sign-up process with an AuthFlow of USER_AUTH and AuthParameters of EMAIL_OTP or SMS_OTP, depending on how your user pool sent the confirmation-code message.

Value

A list with the following syntax:

list(
  ChallengeName = "SMS_MFA"|"EMAIL_OTP"|"SOFTWARE_TOKEN_MFA"|"SELECT_MFA_TYPE"|"MFA_SETUP"|"PASSWORD_VERIFIER"|"CUSTOM_CHALLENGE"|"SELECT_CHALLENGE"|"DEVICE_SRP_AUTH"|"DEVICE_PASSWORD_VERIFIER"|"ADMIN_NO_SRP_AUTH"|"NEW_PASSWORD_REQUIRED"|"SMS_OTP"|"PASSWORD"|"WEB_AUTHN"|"PASSWORD_SRP",
  Session = "string",
  ChallengeParameters = list(
    "string"
  ),
  AuthenticationResult = list(
    AccessToken = "string",
    ExpiresIn = 123,
    TokenType = "string",
    RefreshToken = "string",
    IdToken = "string",
    NewDeviceMetadata = list(
      DeviceKey = "string",
      DeviceGroupKey = "string"
    )
  ),
  AvailableChallenges = list(
    "SMS_MFA"|"EMAIL_OTP"|"SOFTWARE_TOKEN_MFA"|"SELECT_MFA_TYPE"|"MFA_SETUP"|"PASSWORD_VERIFIER"|"CUSTOM_CHALLENGE"|"SELECT_CHALLENGE"|"DEVICE_SRP_AUTH"|"DEVICE_PASSWORD_VERIFIER"|"ADMIN_NO_SRP_AUTH"|"NEW_PASSWORD_REQUIRED"|"SMS_OTP"|"PASSWORD"|"WEB_AUTHN"|"PASSWORD_SRP"
  )
)

Request syntax

svc$admin_initiate_auth(
  UserPoolId = "string",
  ClientId = "string",
  AuthFlow = "USER_SRP_AUTH"|"REFRESH_TOKEN_AUTH"|"REFRESH_TOKEN"|"CUSTOM_AUTH"|"ADMIN_NO_SRP_AUTH"|"USER_PASSWORD_AUTH"|"ADMIN_USER_PASSWORD_AUTH"|"USER_AUTH",
  AuthParameters = list(
    "string"
  ),
  ClientMetadata = list(
    "string"
  ),
  AnalyticsMetadata = list(
    AnalyticsEndpointId = "string"
  ),
  ContextData = list(
    IpAddress = "string",
    ServerName = "string",
    ServerPath = "string",
    HttpHeaders = list(
      list(
        headerName = "string",
        headerValue = "string"
      )
    ),
    EncodedData = "string"
  ),
  Session = "string"
)