Amazon Cognito Identity Pool Construct Library---
AWS CDK v1 has reached End-of-Support on 2023-06-01. This package is no longer being updated, and users should migrate to AWS CDK v2.
For more information on how to migrate, see the Migrating to AWS CDK v2 guide.
Amazon Cognito Identity Pools enable you to grant your users access to other AWS services.
Identity Pools are one of the two main components of Amazon Cognito, which provides authentication, authorization, and user management for your web and mobile apps. Your users can sign in directly with a user name and password, or through a third party such as Facebook, Amazon, Google or Apple.
The other main component in Amazon Cognito is user pools. User Pools are user directories that provide sign-up and sign-in options for your app users.
This module is part of the AWS Cloud Development Kit project.
from aws_cdk.aws_cognito_identitypool import IdentityPool, UserPoolAuthenticationProvider
Table of Contents
Identity pools provide temporary AWS credentials for users who are guests (unauthenticated) and for users who have been authenticated and received a token. An identity pool is a store of user identity data specific to an account.
Identity pools can be used in conjunction with Cognito User Pools or by accessing external federated identity providers directly. Learn more at Amazon Cognito Identity Pools.
Authenticated and Unauthenticated Identities
Identity pools define two types of identities: authenticated(
user) and unauthenticated (
guest). Every identity in
an identity pool is either authenticated or unauthenticated. Each identity pool has a default role for authenticated
identities, and a default role for unauthenticated identities. Absent other overriding rules (see below), these are the
roles that will be assumed by the corresponding users in the authentication process.
A basic Identity Pool with minimal configuration has no required props, with default authenticated (user) and unauthenticated (guest) roles applied to the identity pool:
By default, both the authenticated and unauthenticated roles will have no permissions attached. Grant permissions
to roles using the public
import aws_cdk.aws_dynamodb as dynamodb # table: dynamodb.Table identity_pool = IdentityPool(self, "myIdentityPool") # Grant permissions to authenticated users table.grant_read_write_data(identity_pool.authenticated_role) # Grant permissions to unauthenticated guest users table.grant_read_data(identity_pool.unauthenticated_role) # Or add policy statements straight to the role identity_pool.authenticated_role.add_to_principal_policy(iam.PolicyStatement( effect=iam.Effect.ALLOW, actions=["dynamodb:*"], resources=["*"] ))
The default roles can also be supplied in
stack = Stack() authenticated_role = iam.Role(self, "authRole", assumed_by=iam.ServicePrincipal("service.amazonaws.com") ) unauthenticated_role = iam.Role(self, "unauthRole", assumed_by=iam.ServicePrincipal("service.amazonaws.com") ) identity_pool = IdentityPool(self, "TestIdentityPoolActions", authenticated_role=authenticated_role, unauthenticated_role=unauthenticated_role )
Authenticated identities belong to users who are authenticated by a public login provider (Amazon Cognito user pools, Login with Amazon, Sign in with Apple, Facebook, Google, SAML, or any OpenID Connect Providers) or a developer provider (your own backend authentication process).
Authentication providers can be associated with an Identity Pool by first associating them with a Cognito User Pool or by associating the provider directly with the identity pool.
User Pool Authentication Provider
In order to attach a user pool to an identity pool as an authentication provider, the identity pool needs properties
from both the user pool and the user pool client. For this reason identity pools use a
to gather the necessary properties from the user pool constructs.
user_pool = cognito.UserPool(self, "Pool") IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", authentication_providers=IdentityPoolAuthenticationProviders( user_pools=[UserPoolAuthenticationProvider(user_pool=user_pool)] ) )
User pools can also be associated with an identity pool after instantiation. The Identity Pool’s
returns the User Pool Client that has been created:
# identity_pool: IdentityPool user_pool = cognito.UserPool(self, "Pool") user_pool_client = identity_pool.add_user_pool_authentication(UserPoolAuthenticationProvider( user_pool=user_pool ))
Server Side Token Check
IdentityPool CDK Construct, by default the pool is configured to check with the integrated user pools to
make sure that the user has not been globally signed out or deleted before the identity pool provides an OIDC token or
AWS credentials for the user.
If the user is signed out or deleted, the identity pool will return a 400 Not Authorized error. This setting can be disabled, however, in several ways.
disableServerSideTokenCheck to true will change the default behavior to no server side token check. Learn
# identity_pool: IdentityPool user_pool = cognito.UserPool(self, "Pool") identity_pool.add_user_pool_authentication(UserPoolAuthenticationProvider( user_pool=user_pool, disable_server_side_token_check=True ))
Associating an External Provider Directly
One or more external identity providers can be associated with an identity pool directly using
IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", authentication_providers=IdentityPoolAuthenticationProviders( amazon=IdentityPoolAmazonLoginProvider( app_id="amzn1.application.12312k3j234j13rjiwuenf" ), facebook=IdentityPoolFacebookLoginProvider( app_id="1234567890123" ), google=IdentityPoolGoogleLoginProvider( client_id="12345678012.apps.googleusercontent.com" ), apple=IdentityPoolAppleLoginProvider( services_id="com.myappleapp.auth" ), twitter=IdentityPoolTwitterLoginProvider( consumer_key="my-twitter-id", consumer_secret="my-twitter-secret" ) ) )
To associate more than one provider of the same type with the identity pool, use User Pools, OpenIdConnect, or SAML. Only one provider per external service can be attached directly to the identity pool.
OpenId Connect and Saml
OpenID Connect is an open standard for authentication that is supported by a number of login providers. Amazon Cognito supports linking of identities with OpenID Connect providers that are configured through AWS Identity and Access Management.
An identity provider that supports Security Assertion Markup Language 2.0 (SAML 2.0) can be used to provide a simple onboarding flow for users. The SAML-supporting identity provider specifies the IAM roles that can be assumed by users so that different users can be granted different sets of permissions. Associating an OpenId Connect or Saml provider with an identity pool:
# open_id_connect_provider: iam.OpenIdConnectProvider # saml_provider: iam.SamlProvider IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", authentication_providers=IdentityPoolAuthenticationProviders( open_id_connect_providers=[open_id_connect_provider], saml_providers=[saml_provider] ) )
The identity pool’s behavior can be customized further using custom developer authenticated identities. With developer authenticated identities, users can be registered and authenticated via an existing authentication process while still using Amazon Cognito to synchronize user data and access AWS resources.
Like the supported external providers, though, only one custom provider can be directly associated with the identity pool.
# open_id_connect_provider: iam.OpenIdConnectProvider IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", authentication_providers=IdentityPoolAuthenticationProviders( google=IdentityPoolGoogleLoginProvider( client_id="12345678012.apps.googleusercontent.com" ), open_id_connect_providers=[open_id_connect_provider], custom_provider="my-custom-provider.example.com" ) )
In addition to setting default roles for authenticated and unauthenticated users, identity pools can also be used to define rules to choose the role for each user based on claims in the user’s ID token by using Role Mapping. When using role mapping, it’s important to be aware of some of the permissions the role will need. An in depth review of roles and role mapping can be found here.
Using a token-based approach to role mapping will allow mapped roles to be passed through the
cognito:preferred_role claims from the identity provider:
from aws_cdk.aws_cognito_identitypool import IdentityPoolProviderUrl IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", role_mappings=[IdentityPoolRoleMapping( provider_url=IdentityPoolProviderUrl.AMAZON, use_token=True )] )
Using a rule-based approach to role mapping allows roles to be assigned based on custom claims passed from the identity provider:
from aws_cdk.aws_cognito_identitypool import IdentityPoolProviderUrl, RoleMappingMatchType # admin_role: iam.Role # non_admin_role: iam.Role IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", # Assign specific roles to users based on whether or not the custom admin claim is passed from the identity provider role_mappings=[IdentityPoolRoleMapping( provider_url=IdentityPoolProviderUrl.AMAZON, rules=[RoleMappingRule( claim="custom:admin", claim_value="admin", mapped_role=admin_role ), RoleMappingRule( claim="custom:admin", claim_value="admin", match_type=RoleMappingMatchType.NOTEQUAL, mapped_role=non_admin_role ) ] )] )
Role mappings can also be added after instantiation with the Identity Pool’s
from aws_cdk.aws_cognito_identitypool import IdentityPoolRoleMapping # identity_pool: IdentityPool # my_added_role_mapping1: IdentityPoolRoleMapping # my_added_role_mapping2: IdentityPoolRoleMapping # my_added_role_mapping3: IdentityPoolRoleMapping identity_pool.add_role_mappings(my_added_role_mapping1, my_added_role_mapping2, my_added_role_mapping3)
Role mappings must be associated with the url of an Identity Provider which can be supplied
IdentityPoolProviderUrl. Supported Providers have static Urls that can be used:
from aws_cdk.aws_cognito_identitypool import IdentityPoolProviderUrl IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", role_mappings=[IdentityPoolRoleMapping( provider_url=IdentityPoolProviderUrl.FACEBOOK, use_token=True )] )
For identity providers that don’t have static Urls, a custom Url or User Pool Client Url can be supplied:
from aws_cdk.aws_cognito_identitypool import IdentityPoolProviderUrl IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", role_mappings=[IdentityPoolRoleMapping( provider_url=IdentityPoolProviderUrl.user_pool("cognito-idp.my-idp-region.amazonaws.com/my-idp-region_abcdefghi:app_client_id"), use_token=True ), IdentityPoolRoleMapping( provider_url=IdentityPoolProviderUrl.custom("my-custom-provider.com"), use_token=True ) ] )
See here for more information.
Identity Pool Authentication Flow defaults to the enhanced, simplified flow. The Classic (basic) Authentication Flow
can also be implemented using
IdentityPool(self, "myidentitypool", identity_pool_name="myidentitypool", allow_classic_flow=True )
It’s now recommended to integrate AWS AppSync for synchronizing app data across devices, so
Cognito Sync features like
CognitoStreams are not a part of
information can be found here.
Importing Identity Pools
You can import existing identity pools into your stack using Identity Pool static methods with the Identity Pool Id or Arn:
IdentityPool.from_identity_pool_id(self, "my-imported-identity-pool", "us-east-1:dj2823ryiwuhef937") IdentityPool.from_identity_pool_arn(self, "my-imported-identity-pool", "arn:aws:cognito-identity:us-east-1:123456789012:identitypool/us-east-1:dj2823ryiwuhef937")