You can use Amazon Cognito to deliver temporary, limited-privilege credentials to your application, so that your users can access AWS resources. This section describes how to get credentials and how to retrieve an Amazon Cognito identity from an identity pool.
Amazon Cognito supports both authenticated and unauthenticated identities. Unauthenticated users do not have their identity verified, making this role appropriate for guest users of your app or in cases when it doesn't matter if users have their identities verified. Authenticated users log in to your application through a third-party identity provider, or a user pool, that verifies their identities. Make sure you scope the permissions of resources appropriately so you don't grant access to them from unauthenticated users.
Amazon Cognito identities are not credentials. They are exchanged for credentials using web
identity federation support in the AWS Security Token Service (AWS STS). The recommended way to obtain AWS
credentials for your app users is to use AWS.CognitoIdentityCredentials
. The
identity in the credentials object is then exchanged for credentials using AWS STS.
Note
If you created your identity pool before February 2015, you must reassociate your roles
with your identity pool to use the AWS.CognitoIdentityCredentials
constructor
without the roles as parameters. To do so, open the Amazon Cognito console
Web identity credentials providers are part of the default credential provider chain in
AWS SDKs. To set your identity pool token in a local config
file for an AWS
SDK or the AWS CLI, add a web_identity_token_file
profile entry. See Assume
role credential provider in the AWS SDKs and Tools Reference Guide.
To learn more about how to populate web identity credentials in your SDK, refer to the SDK developer guide. For best results, start your project with the identity pool integration that's built in to AWS Amplify.
AWS SDK resources for getting and setting credentials with identity pools
-
Identity Pool Federation
(Android) in the Amplify Dev Center -
Identity Pool Federation
(iOS) in the Amplify Dev Center -
Using Amazon Cognito Identity to authenticate users in the AWS SDK for JavaScript Developer Guide
-
Amazon Cognito credentials provider in the AWS SDK for .NET Developer Guide
-
Specify Credentials Programmatically
in the AWS SDK for Go Developer Guide -
Supply temporary credentials in code in the AWS SDK for Java 2.x Developer Guide
-
assumeRoleWithWebIdentityCredentialProvider provider in the AWS SDK for PHP Developer Guide
-
Assume Role With Web Identity Provider
in the AWS SDK for Python (Boto3) documentation -
Specifying your credentials and default region in the AWS SDK for Rust Developer Guide
The following sections provide example code in some legacy AWS SDKs.
You can use Amazon Cognito to deliver temporary, limited-privilege credentials to your application, so that your users can access AWS resources. Amazon Cognito supports both authenticated and unauthenticated identities. To provide AWS credentials to your app, follow the steps below.
To use a Amazon Cognito identity pool in an Android app, set up AWS Amplify. For more
information, see Authentication
Retrieving an Amazon Cognito identity
If you're allowing unauthenticated users, you can retrieve a unique Amazon Cognito identifier (identity ID) for your end user immediately. If you're authenticating users, you can retrieve the identity ID after you've set the login tokens in the credentials provider:
String identityId = credentialsProvider.getIdentityId();
Log.d("LogTag", "my ID is " + identityId);
Note
Do not call getIdentityId()
, refresh()
, or
getCredentials()
in the main thread of your application. As of Android
3.0 (API Level 11), your app will automatically fail and throw a NetworkOnMainThreadExceptionAsyncTask
. For more information, consult the Android documentationgetCachedIdentityId()
to retrieve an ID, but only if one is already cached locally. Otherwise, the method will
return null.
You can use Amazon Cognito to deliver temporary, limited-privilege credentials to your application, so that your users can access AWS resources. Amazon Cognito identity pools support both authenticated and unauthenticated identities. To provide AWS credentials to your app, complete the following steps.
To use a Amazon Cognito identity pool in an iOS app, set up AWS Amplify. For more
information, see Swift
Authentication
Retrieving an Amazon Cognito identity
You can retrieve a unique Amazon Cognito identifier (identity ID) for your end user immediately if you're allowing unauthenticated users or after you've set the login tokens in the credentials provider if you're authenticating users:
// Retrieve your Amazon Cognito ID
[[credentialsProvider getIdentityId] continueWithBlock:^id(AWSTask *task) {
if (task.error) {
NSLog(@"Error: %@", task.error);
}
else {
// the task result will contain the identity id
NSString *cognitoId = task.result;
}
return nil;
}];
Note
getIdentityId
is an asynchronous call. If an identity ID is already set on
your provider, you can call credentialsProvider.identityId
to retrieve that
identity, which is cached locally. However, if an identity ID is not set on your
provider, calling credentialsProvider.identityId
will return
nil
. For more information, consult the Amplify iOS SDK reference
You can use Amazon Cognito to deliver temporary, limited-privilege credentials to your application so that your users can access AWS resources. Amazon Cognito supports both authenticated and unauthenticated identities. To provide AWS credentials to your app, follow the steps below.
To use a Amazon Cognito identity pool in an iOS app, set up AWS Amplify. For more
information, see Swift
Authentication
Retrieving an Amazon Cognito identity
You can retrieve a unique Amazon Cognito identifier (identity ID) for your end user immediately if you're allowing unauthenticated users or after you've set the login tokens in the credentials provider if you're authenticating users:
// Retrieve your Amazon Cognito ID
credentialsProvider.getIdentityId().continueWith(block: { (task) -> AnyObject? in
if (task.error != nil) {
print("Error: " + task.error!.localizedDescription)
}
else {
// the task result will contain the identity id
let cognitoId = task.result!
print("Cognito id: \(cognitoId)")
}
return task;
})
Note
getIdentityId
is an asynchronous call. If an identity ID is already set on
your provider, you can call credentialsProvider.identityId
to retrieve that
identity, which is cached locally. However, if an identity ID is not set on your
provider, calling credentialsProvider.identityId
will return
nil
. For more information, consult the Amplify iOS SDK reference
If you have not yet created one, create an identity pool in the Amazon Cognito consoleAWS.CognitoIdentityCredentials
.
After you configure an identity pool with your identity providers, you can use
AWS.CognitoIdentityCredentials
to authenticate users. To configure your
application credentials to use AWS.CognitoIdentityCredentials
, set the
credentials
property of either AWS.Config
or a per-service
configuration. The following example uses AWS.Config
:
// Set the region where your identity pool exists (us-east-1, eu-west-1)
AWS.config.region = 'us-east-1';
// Configure the credentials provider to use your identity pool
AWS.config.credentials = new AWS.CognitoIdentityCredentials({
IdentityPoolId: 'IDENTITY_POOL_ID',
Logins: { // optional tokens, used for authenticated login
'graph.facebook.com': 'FBTOKEN',
'www.amazon.com': 'AMAZONTOKEN',
'accounts.google.com': 'GOOGLETOKEN',
'appleid.apple.com': 'APPLETOKEN'
}
});
// Make the call to obtain credentials
AWS.config.credentials.get(function(){
// Credentials will be available when this function is called.
var accessKeyId = AWS.config.credentials.accessKeyId;
var secretAccessKey = AWS.config.credentials.secretAccessKey;
var sessionToken = AWS.config.credentials.sessionToken;
});
The optional Logins
property is a map of identity provider names to the
identity tokens for those providers. How you get the token from your identity provider
depends on the provider you use. For example, if Facebook is one of your identity
providers, you might use the FB.login
function from the Facebook SDK
FB.login(function (response) {
if (response.authResponse) { // logged in
AWS.config.credentials = new AWS.CognitoIdentityCredentials({
IdentityPoolId: 'us-east-1:1699ebc0-7900-4099-b910-2df94f52a030',
Logins: {
'graph.facebook.com': response.authResponse.accessToken
}
});
console.log('You are now logged in.');
} else {
console.log('There was a problem logging you in.');
}
});
Retrieving an Amazon Cognito identity
You can retrieve a unique Amazon Cognito identifier (identity ID) for your end user immediately if you're allowing unauthenticated users or after you've set the login tokens in the credentials provider if you're authenticating users:
var identityId = AWS.config.credentials.identityId;
You can use Amazon Cognito to deliver temporary, limited-privilege credentials to your application, so that your users can access AWS resources. Amazon Cognito supports both authenticated and unauthenticated identities. To provide AWS credentials to your app, follow the steps below.
The AWS SDK for
Unity is now part of the AWS SDK for .NET. To get started with
Amazon Cognito in the AWS SDK for .NET, see Amazon Cognito credentials
provider in the AWS SDK for .NET Developer Guide. Or see Amplify Dev Center
Retrieving an Amazon Cognito identity
You can retrieve a unique Amazon Cognito identifier (identity ID) for your end user immediately if you're allowing unauthenticated users or after you've set the login tokens in the credentials provider if you're authenticating users:
credentials.GetIdentityIdAsync(delegate(AmazonCognitoIdentityResult<string> result) {
if (result.Exception != null) {
//Exception!
}
string identityId = result.Response;
});
You can use Amazon Cognito to deliver temporary, limited-privilege credentials to your application so that your users can access AWS resources. Amazon Cognito supports both authenticated and unauthenticated identities. To provide AWS credentials to your app, follow the steps below.
The AWS SDK for Xamarin is now part of the AWS SDK for .NET. To get started with
Amazon Cognito in the AWS SDK for .NET, see Amazon Cognito credentials
provider in the AWS SDK for .NET Developer Guide. Or see Amplify Dev Center
Note
Note: If you created your identity pool before February
2015, you must reassociate your roles with your identity pool in order to use this
constructor without the roles as parameters. To do so, open the Amazon Cognito console
Retrieving an Amazon Cognito identity
You can retrieve a unique Amazon Cognito identifier (identity ID) for your end user immediately if you're allowing unauthenticated users or after you've set the login tokens in the credentials provider if you're authenticating users:
var identityId = await credentials.GetIdentityIdAsync();