Class: AWS.WebIdentityCredentials

AWS.Credentials show all
Defined in:


Represents credentials retrieved from STS Web Identity Federation support.

By default this provider gets credentials using the AWS.STS.assumeRoleWithWebIdentity() service operation. This operation requires a RoleArn containing the ARN of the IAM trust policy for the application for which credentials will be given. In addition, the WebIdentityToken must be set to the token provided by the identity provider. See constructor() for an example on creating a credentials object with proper RoleArn and WebIdentityToken values.

Refreshing Credentials from Identity Service

In addition to AWS credentials expiring after a given amount of time, the login token from the identity provider will also expire. Once this token expires, it will not be usable to refresh AWS credentials, and another token will be needed. The SDK does not manage refreshing of the token value, but this can be done through a "refresh token" supported by most identity providers. Consult the documentation for the identity provider for refreshing tokens. Once the refreshed token is acquired, you should make sure to update this new token in the credentials object's params property. The following code will update the WebIdentityToken, assuming you have retrieved an updated token from the identity provider:

AWS.config.credentials.params.WebIdentityToken = updatedToken;

Future calls to credentials.refresh() will now use the new token.

Constructor Summary

Property Summary

Properties inherited from AWS.Credentials

expired, expireTime, accessKeyId, secretAccessKey, sessionToken, expiryWindow

Method Summary

Methods inherited from AWS.Credentials

needsRefresh, get, getPromise, refreshPromise

Constructor Details

new AWS.WebIdentityCredentials(params, clientConfig) ⇒ void

Creates a new credentials object.


Creating a new credentials object

AWS.config.credentials = new AWS.WebIdentityCredentials({
  RoleArn: 'arn:aws:iam::1234567890:role/WebIdentity',
  WebIdentityToken: 'ABCDEFGHIJKLMNOP', // token from identity service
  RoleSessionName: 'web' // optional name, defaults to web-identity
}, {
  // optionally provide configuration to apply to the underlying AWS.STS service client
  // if configuration is not provided, then configuration will be pulled from AWS.config

  // specify timeout options
  httpOptions: {
    timeout: 100


  • params (Object)
    • RoleArn — (String)

      The Amazon Resource Name (ARN) of the role that the caller is assuming.

    • RoleSessionName — (String)

      An identifier for the assumed role session. Typically, you pass the name or identifier that is associated with the user who is using your application. That way, the temporary security credentials that your application will use are associated with that user. This session name is included as part of the ARN and assumed role ID in the AssumedRoleUser response element.

      The regex used to validate this parameter is a string of characters consisting of upper- and lower-case alphanumeric characters with no spaces. You can also include underscores or any of the following characters: =,.@-

    • WebIdentityToken — (String)

      The OAuth 2.0 access token or OpenID Connect ID token that is provided by the identity provider. Your application must get this token by authenticating the user who is using your application with a web identity provider before the application makes an AssumeRoleWithWebIdentity call.

    • ProviderId — (String)

      The fully qualified host component of the domain name of the identity provider.

      Specify this value only for OAuth 2.0 access tokens. Currently and are the only supported identity providers for OAuth 2.0 access tokens. Do not include URL schemes and port numbers.

      Do not specify this value for OpenID Connect ID tokens.

    • Policy — (String)

      An IAM policy in JSON format.

      The policy parameter is optional. If you pass a policy, the temporary security credentials that are returned by the operation have the permissions that are allowed by both the access policy of the role that is being assumed, and the policy that you pass. This gives you a way to further restrict the permissions for the resulting temporary security credentials. You cannot use the passed policy to grant permissions that are in excess of those allowed by the access policy of the role that is being assumed. For more information, see Permissions for AssumeRoleWithWebIdentity in the IAM User Guide.

      The format for this parameter, as described by its regex pattern, is a string of characters up to 2048 characters in length. The characters can be any ASCII character from the space character to the end of the valid character list (\u0020-\u00FF). It can also include the tab (\u0009), linefeed (\u000A), and carriage return (\u000D) characters.

      Note: The policy plain text must be 2048 bytes or shorter. However, an internal conversion compresses it into a packed binary format with a separate limit. The PackedPolicySize response element indicates by percentage how close to the upper size limit the policy is, with 100% equaling the maximum allowed size.
    • DurationSeconds — (Integer)

      The duration, in seconds, of the role session. The value can range from 900 seconds (15 minutes) up to the maximum session duration setting for the role. This setting can have a value from 1 hour to 12 hours. If you specify a value higher than this setting, the operation fails. For example, if you specify a session duration of 12 hours, but your administrator set the maximum session duration to 6 hours, your operation fails. To learn how to view the maximum value for your role, see View the Maximum Session Duration Setting for a Role in the IAM User Guide.

      By default, the value is set to 3600 seconds.

      Note: The DurationSeconds parameter is separate from the duration of a console session that you might request using the returned credentials. The request to the federation endpoint for a console sign-in token takes a SessionDuration parameter that specifies the maximum length of the console session. For more information, see Creating a URL that Enables Federated Users to Access the AWS Management Console in the IAM User Guide.

See Also:

Property Details

datamap (readwrite)

Returns the raw data response from the call to AWS.STS.assumeRoleWithWebIdentity(). Use this if you want to get access to other properties from the response.


paramsmap (readwrite)

Returns the map of params passed to AWS.STS.assumeRoleWithWebIdentity(). To update the token, set the params.WebIdentityToken property.


Method Details

refresh(callback) ⇒ void

Refreshes credentials using AWS.STS.assumeRoleWithWebIdentity()

Callback (callback):

  • function(err) { ... }

    Called when the STS service responds (or fails). When this callback is called with no error, it means that the credentials information has been loaded into the object (as the accessKeyId, secretAccessKey, and sessionToken properties).


    • err (Error)

      if an error occurred, this value will be filled

See Also:

  • AWS.WebIdentityCredentials.get