[ aws . cognito-idp ]
initiate-auth
Description
Declares an authentication flow and initiates sign-in for a user in the Amazon Cognito user directory. Amazon Cognito might respond with an additional challenge or an AuthenticationResult that contains the outcome of a successful authentication. You can’t sign in a user with a federated IdP with InitiateAuth . For more information, see Authentication .
Note
Amazon Cognito doesn’t evaluate Identity and Access Management (IAM) policies in requests for this API operation. For this operation, you can’t use IAM credentials to authorize requests, and you can’t grant IAM permissions in policies. For more information about authorization models in Amazon Cognito, see Using the Amazon Cognito user pools API and user pool endpoints .Note
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 .
See also: AWS API Documentation
Synopsis
initiate-auth
--auth-flow <value>
[--auth-parameters <value>]
[--client-metadata <value>]
--client-id <value>
[--analytics-metadata <value>]
[--user-context-data <value>]
[--session <value>]
[--cli-input-json | --cli-input-yaml]
[--generate-cli-skeleton <value>]
[--debug]
[--endpoint-url <value>]
[--no-verify-ssl]
[--no-paginate]
[--output <value>]
[--query <value>]
[--profile <value>]
[--region <value>]
[--version <value>]
[--color <value>]
[--no-sign-request]
[--ca-bundle <value>]
[--cli-read-timeout <value>]
[--cli-connect-timeout <value>]
[--cli-binary-format <value>]
[--no-cli-pager]
[--cli-auto-prompt]
[--no-cli-auto-prompt]
Options
--auth-flow (string)
The authentication flow that you want to initiate. Each AuthFlow has linked AuthParameters that you must submit. The following are some example flows.
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.
Username-password authentication with the Secure Remote Password (SRP) protocol. For more information, see Use SRP password verification in custom authentication flow .
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 authentication with Lambda triggers. For more information, see Custom authentication challenge Lambda triggers .
Client-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 .
ADMIN_USER_PASSWORD_AUTH is a flow type of AdminInitiateAuth and isn’t valid for InitiateAuth. ADMIN_NO_SRP_AUTH is a legacy server-side username-password flow and isn’t valid for InitiateAuth.Possible values:
USER_SRP_AUTHREFRESH_TOKEN_AUTHREFRESH_TOKENCUSTOM_AUTHADMIN_NO_SRP_AUTHUSER_PASSWORD_AUTHADMIN_USER_PASSWORD_AUTHUSER_AUTH
--auth-parameters (map)
The authentication parameters. These are inputs corresponding to the AuthFlow that you’re invoking.
The required values are specific to the InitiateAuthRequest$AuthFlow .
The following are some authentication flows and their parameters. Add a SECRET_HASH parameter if your app client has a client secret.
-
USER_AUTH:USERNAME(required),PREFERRED_CHALLENGE. If you don’t provide a value forPREFERRED_CHALLENGE, Amazon Cognito responds with theAvailableChallengesparameter that specifies the available sign-in methods. -
USER_SRP_AUTH:USERNAME(required),SRP_A(required),DEVICE_KEY. -
USER_PASSWORD_AUTH:USERNAME(required),PASSWORD(required),DEVICE_KEY. -
REFRESH_TOKEN_AUTH/REFRESH_TOKEN:REFRESH_TOKEN(required),DEVICE_KEY. -
CUSTOM_AUTH:USERNAME(required),SECRET_HASH(if app client is configured with client secret),DEVICE_KEY. To start the authentication flow with password verification, includeChallengeName: SRP_AandSRP_A: (The SRP_A Value).
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 .
key -> (string)
value -> (string)
Shorthand Syntax:
KeyName1=string,KeyName2=string
JSON Syntax:
{"string": "string"
...}
--client-metadata (map)
A map of custom key-value pairs that you can provide as input for certain custom workflows that this action triggers.
You create custom workflows by assigning Lambda functions to user pool triggers. When you send an InitiateAuth request, Amazon Cognito invokes the Lambda functions that are specified for various triggers. The ClientMetadata value is passed as input to the functions for only the following triggers.
- Pre sign-up
- Pre authentication
- User migration
When Amazon Cognito invokes the functions for these triggers, it passes a JSON payload as input to the function. This payload contains a validationData attribute with the data that you assigned to the ClientMetadata parameter in your InitiateAuth request. In your function, validationData can contribute to operations that require data that isn’t in the default payload.
InitiateAuth requests invokes the following triggers without ClientMetadata as input.- Post authentication
- Custom message
- Pre token generation
- Create auth challenge
- Define auth challenge
- Custom email sender
- Custom SMS sender
For more information, see Using Lambda triggers in the Amazon Cognito Developer Guide .
Note
When you use the ClientMetadata parameter, note that Amazon Cognito won’t do the following:
- Store the
ClientMetadatavalue. 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, theClientMetadataparameter serves no purpose. - Validate the
ClientMetadatavalue. - Encrypt the
ClientMetadatavalue. Don’t send sensitive information in this parameter.
key -> (string)
value -> (string)
Shorthand Syntax:
KeyName1=string,KeyName2=string
JSON Syntax:
{"string": "string"
...}
--client-id (string)
--analytics-metadata (structure)
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.
AnalyticsEndpointId -> (string)
Shorthand Syntax:
AnalyticsEndpointId=string
JSON Syntax:
{
"AnalyticsEndpointId": "string"
}
--user-context-data (structure)
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 .
IpAddress -> (string)
EncodedData -> (string)
Shorthand Syntax:
IpAddress=string,EncodedData=string
JSON Syntax:
{
"IpAddress": "string",
"EncodedData": "string"
}
--session (string)
ConfirmSignUp API request. You can sign in a user directly from the sign-up process with the USER_AUTH authentication flow. When you pass the session ID to InitiateAuth , Amazon Cognito assumes the SMS or email message one-time verification password from ConfirmSignUp as the primary authentication factor. You’re not required to submit this code a second time. This option is only valid for users who have confirmed their sign-up and are signing in for the first time within the authentication flow session duration of the session ID.--cli-input-json | --cli-input-yaml (string) Reads arguments from the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton. If other arguments are provided on the command line, those values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally. This may not be specified along with --cli-input-yaml.
--generate-cli-skeleton (string) Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input, prints a sample input JSON that can be used as an argument for --cli-input-json. Similarly, if provided yaml-input it will print a sample input YAML that can be used with --cli-input-yaml. If provided with the value output, it validates the command inputs and returns a sample output JSON for that command. The generated JSON skeleton is not stable between versions of the AWS CLI and there are no backwards compatibility guarantees in the JSON skeleton generated.
Global Options
--debug (boolean)
Turn on debug logging.
--endpoint-url (string)
Override command’s default URL with the given URL.
--no-verify-ssl (boolean)
By default, the AWS CLI uses SSL when communicating with AWS services. For each SSL connection, the AWS CLI will verify SSL certificates. This option overrides the default behavior of verifying SSL certificates.
--no-paginate (boolean)
Disable automatic pagination. If automatic pagination is disabled, the AWS CLI will only make one call, for the first page of results.
--output (string)
The formatting style for command output.
- json
- text
- table
- yaml
- yaml-stream
--query (string)
A JMESPath query to use in filtering the response data.
--profile (string)
Use a specific profile from your credential file.
--region (string)
The region to use. Overrides config/env settings.
--version (string)
Display the version of this tool.
--color (string)
Turn on/off color output.
- on
- off
- auto
--no-sign-request (boolean)
Do not sign requests. Credentials will not be loaded if this argument is provided.
--ca-bundle (string)
The CA certificate bundle to use when verifying SSL certificates. Overrides config/env settings.
--cli-read-timeout (int)
The maximum socket read time in seconds. If the value is set to 0, the socket read will be blocking and not timeout. The default value is 60 seconds.
--cli-connect-timeout (int)
The maximum socket connect time in seconds. If the value is set to 0, the socket connect will be blocking and not timeout. The default value is 60 seconds.
--cli-binary-format (string)
The formatting style to be used for binary blobs. The default format is base64. The base64 format expects binary blobs to be provided as a base64 encoded string. The raw-in-base64-out format preserves compatibility with AWS CLI V1 behavior and binary values must be passed literally. When providing contents from a file that map to a binary blob fileb:// will always be treated as binary and use the file contents directly regardless of the cli-binary-format setting. When using file:// the file contents will need to properly formatted for the configured cli-binary-format.
- base64
- raw-in-base64-out
--no-cli-pager (boolean)
Disable cli pager for output.
--cli-auto-prompt (boolean)
Automatically prompt for CLI input parameters.
--no-cli-auto-prompt (boolean)
Disable automatically prompt for CLI input parameters.
Examples
Note
To use the following examples, you must have the AWS CLI installed and configured. See the Getting started guide in the AWS CLI User Guide for more information.
Unless otherwise stated, all examples have unix-like quotation rules. These examples will need to be adapted to your terminal’s quoting rules. See Using quotation marks with strings in the AWS CLI User Guide .
To sign in a user
The following initiate-auth example signs in a user with the basic username-password flow and no additional challenges.
aws cognito-idp initiate-auth \
--auth-flow USER_PASSWORD_AUTH \
--client-id 1example23456789 \
--analytics-metadata AnalyticsEndpointId=d70b2ba36a8c4dc5a04a0451aEXAMPLE \
--auth-parameters USERNAME=testuser,PASSWORD=[Password] --user-context-data EncodedData=mycontextdata --client-metadata MyTestKey=MyTestValue
Output:
{
"AuthenticationResult": {
"AccessToken": "eyJra456defEXAMPLE",
"ExpiresIn": 3600,
"TokenType": "Bearer",
"RefreshToken": "eyJra123abcEXAMPLE",
"IdToken": "eyJra789ghiEXAMPLE",
"NewDeviceMetadata": {
"DeviceKey": "us-west-2_a1b2c3d4-5678-90ab-cdef-EXAMPLE11111",
"DeviceGroupKey": "-v7w9UcY6"
}
}
}
For more information, see Authentication in the Amazon Cognito Developer Guide.
Output
ChallengeName -> (string)
The name of an additional authentication challenge that you must respond to.
Possible challenges include the following:
Note
All of the following challenges requireUSERNAME and, when the app client has a client secret, SECRET_HASH in the parameters.-
WEB_AUTHN: Respond to the challenge with the results of a successful authentication with a WebAuthn authenticator, or passkey. Examples of WebAuthn authenticators include biometric devices and security keys. -
PASSWORD: Respond withUSER_PASSWORD_AUTHparameters:USERNAME(required),PASSWORD(required),SECRET_HASH(required if the app client is configured with a client secret),DEVICE_KEY. -
PASSWORD_SRP: Respond withUSER_SRP_AUTHparameters:USERNAME(required),SRP_A(required),SECRET_HASH(required if the app client is configured with a client secret),DEVICE_KEY. -
SELECT_CHALLENGE: Respond to the challenge withUSERNAMEand anANSWERthat matches one of the challenge types in theAvailableChallengesresponse parameter. -
SMS_MFA: Respond with anSMS_MFA_CODEthat your user pool delivered in an SMS message. -
EMAIL_OTP: Respond with anEMAIL_OTP_CODEthat your user pool delivered in an email message. -
PASSWORD_VERIFIER: Respond withPASSWORD_CLAIM_SIGNATURE,PASSWORD_CLAIM_SECRET_BLOCK, andTIMESTAMPafter client-side SRP calculations. -
CUSTOM_CHALLENGE: This is returned if your custom authentication flow determines that the user should pass another challenge before tokens are issued. The parameters of the challenge are determined by your Lambda function. -
DEVICE_SRP_AUTH: Respond with the initial parameters of device SRP authentication. For more information, see Signing in with a device . -
DEVICE_PASSWORD_VERIFIER: Respond withPASSWORD_CLAIM_SIGNATURE,PASSWORD_CLAIM_SECRET_BLOCK, andTIMESTAMPafter client-side SRP calculations. For more information, see Signing in with a device . -
NEW_PASSWORD_REQUIRED: For users who are required to change their passwords after successful first login. Respond to this challenge withNEW_PASSWORDand any required attributes that Amazon Cognito returned in therequiredAttributesparameter. You can also set values for attributes that aren’t required by your user pool and that your app client can write. Amazon Cognito only returns this challenge for users who have temporary passwords. When you create passwordless users, you must provide values for all required attributes.
Note
In aNEW_PASSWORD_REQUIRED challenge response, you can’t modify a required attribute that already has a value. In AdminRespondToAuthChallenge or RespondToAuthChallenge , set a value for any keys that Amazon Cognito returned in the requiredAttributes parameter, then use the AdminUpdateUserAttributes or UpdateUserAttributes API operation to modify the value of any additional attributes.-
MFA_SETUP: For users who are required to setup an MFA factor before they can sign in. The MFA types activated for the user pool will be listed in the challenge parametersMFAS_CAN_SETUPvalue. To set up time-based one-time password (TOTP) MFA, use the session returned in this challenge fromInitiateAuthorAdminInitiateAuthas an input toAssociateSoftwareToken. Then, use the session returned byVerifySoftwareTokenas an input toRespondToAuthChallengeorAdminRespondToAuthChallengewith challenge nameMFA_SETUPto complete sign-in. To set up SMS or email MFA, collect aphone_numberoremailattribute for the user. Then restart the authentication flow with anInitiateAuthorAdminInitiateAuthrequest.
Session -> (string)
ChallengeParameters -> (map)
The required parameters of the ChallengeName challenge.
All challenges require USERNAME . They also require SECRET_HASH if your app client has a client secret.
key -> (string)
value -> (string)
AuthenticationResult -> (structure)
The result of a successful and complete authentication request. This result is only returned if the user doesn’t need to pass another challenge. If they must pass another challenge before they get tokens, Amazon Cognito returns a challenge in ChallengeName , ChallengeParameters , and Session response parameters.
AccessToken -> (string)
ExpiresIn -> (integer)
TokenType -> (string)
Bearer .RefreshToken -> (string)
IdToken -> (string)
NewDeviceMetadata -> (structure)
The new device metadata from an authentication result.
DeviceKey -> (string)
DEVICE_PASSWORD_VERIFIER for device SRP authentication.DeviceGroupKey -> (string)
DEVICE_PASSWORD_VERIFIER for device SRP authentication.AvailableChallenges -> (list)
This response parameter lists the available authentication challenges that users can select from in choice-based authentication . For example, they might be able to choose between passkey authentication, a one-time password from an SMS message, and a traditional password.
(string)
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