Package com.google.auth.oauth2

Class ImpersonatedCredentials

  • All Implemented Interfaces:
    IdTokenProvider, QuotaProjectIdProvider, ServiceAccountSigner, Serializable
    public class ImpersonatedCredentials
extends GoogleCredentials
implements ServiceAccountSigner, IdTokenProvider
    ImpersonatedCredentials allowing credentials issued to a user or service account to impersonate another. The source project using ImpersonatedCredentials must enable the "IAMCredentials" API. Also, the target service account must grant the originating principal the "Service Account Token Creator" IAM role.

    Usage: 

     String credPath = "/path/to/svc_account.json";
 ServiceAccountCredentials sourceCredentials = ServiceAccountCredentials
     .fromStream(new FileInputStream(credPath));
 sourceCredentials = (ServiceAccountCredentials) sourceCredentials
     .createScoped(Arrays.asList("https://www.googleapis.com/auth/iam"));

 ImpersonatedCredentials targetCredentials = ImpersonatedCredentials.create(sourceCredentials,
     "impersonated-account@project.iam.gserviceaccount.com", null,
     Arrays.asList("https://www.googleapis.com/auth/devstorage.read_only"), 300);

 Storage storage_service = StorageOptions.newBuilder().setProjectId("project-id")
    .setCredentials(targetCredentials).build().getService();

 for (Bucket b : storage_service.list().iterateAll())
     System.out.println(b);
    See Also:
    Serialized Form

    • Method Detail

      • create

        public static ImpersonatedCredentials create​(GoogleCredentials sourceCredentials,
                                             String targetPrincipal,
                                             List<String> delegates,
                                             List<String> scopes,
                                             int lifetime,
                                             HttpTransportFactory transportFactory)
        Parameters:
        sourceCredentials - the source credential used to acquire the impersonated credentials. It should be either a user account credential or a service account credential.
        targetPrincipal - the service account to impersonate
        delegates - the chained list of delegates required to grant the final access_token. If set, the sequence of identities must have "Service Account Token Creator" capability granted to the preceding identity. For example, if set to [serviceAccountB, serviceAccountC], the sourceCredential must have the Token Creator role on serviceAccountB. serviceAccountB must have the Token Creator on serviceAccountC. Finally, C must have Token Creator on target_principal. If unset, sourceCredential must have that role on targetPrincipal.
        scopes - scopes to request during the authorization grant
        lifetime - number of seconds the delegated credential should be valid. By default this value should be at most 3600. However, you can follow these instructions to set up the service account and extend the maximum lifetime to 43200 (12 hours). If the given lifetime is 0, default value 3600 will be used instead when creating the credentials.
        transportFactory - HTTP transport factory that creates the transport used to get access tokens
        Returns:
        new credentials

      • create

        public static ImpersonatedCredentials create​(GoogleCredentials sourceCredentials,
                                             String targetPrincipal,
                                             List<String> delegates,
                                             List<String> scopes,
                                             int lifetime,
                                             HttpTransportFactory transportFactory,
                                             String quotaProjectId)
        Parameters:
        sourceCredentials - the source credential used to acquire the impersonated credentials. It should be either a user account credential or a service account credential.
        targetPrincipal - the service account to impersonate
        delegates - the chained list of delegates required to grant the final access_token. If set, the sequence of identities must have "Service Account Token Creator" capability granted to the preceding identity. For example, if set to [serviceAccountB, serviceAccountC], the sourceCredential must have the Token Creator role on serviceAccountB. serviceAccountB must have the Token Creator on serviceAccountC. Finally, C must have Token Creator on target_principal. If unset, sourceCredential must have that role on targetPrincipal.
        scopes - scopes to request during the authorization grant
        lifetime - number of seconds the delegated credential should be valid. By default this value should be at most 3600. However, you can follow these instructions to set up the service account and extend the maximum lifetime to 43200 (12 hours). If the given lifetime is 0, default value 3600 will be used instead when creating the credentials.
        transportFactory - HTTP transport factory that creates the transport used to get access tokens.
        quotaProjectId - the project used for quota and billing purposes. Should be null unless the caller wants to use a project different from the one that owns the impersonated credential for billing/quota purposes.
        Returns:
        new credentials

      • create

        public static ImpersonatedCredentials create​(GoogleCredentials sourceCredentials,
                                             String targetPrincipal,
                                             List<String> delegates,
                                             List<String> scopes,
                                             int lifetime,
                                             HttpTransportFactory transportFactory,
                                             String quotaProjectId,
                                             String iamEndpointOverride)
        Parameters:
        sourceCredentials - the source credential used to acquire the impersonated credentials. It should be either a user account credential or a service account credential.
        targetPrincipal - the service account to impersonate
        delegates - the chained list of delegates required to grant the final access_token. If set, the sequence of identities must have "Service Account Token Creator" capability granted to the preceding identity. For example, if set to [serviceAccountB, serviceAccountC], the sourceCredential must have the Token Creator role on serviceAccountB. serviceAccountB must have the Token Creator on serviceAccountC. Finally, C must have Token Creator on target_principal. If unset, sourceCredential must have that role on targetPrincipal.
        scopes - scopes to request during the authorization grant
        lifetime - number of seconds the delegated credential should be valid. By default this value should be at most 3600. However, you can follow these instructions to set up the service account and extend the maximum lifetime to 43200 (12 hours). If the given lifetime is 0, default value 3600 will be used instead when creating the credentials.
        transportFactory - HTTP transport factory that creates the transport used to get access tokens.
        quotaProjectId - the project used for quota and billing purposes. Should be null unless the caller wants to use a project different from the one that owns the impersonated credential for billing/quota purposes.
        iamEndpointOverride - The full IAM endpoint override with the target_principal embedded. This is useful when supporting impersonation with regional endpoints.
        Returns:
        new credentials

      • create

        public static ImpersonatedCredentials create​(GoogleCredentials sourceCredentials,
                                             String targetPrincipal,
                                             List<String> delegates,
                                             List<String> scopes,
                                             int lifetime)
        Parameters:
        sourceCredentials - the source credential used to acquire the impersonated credentials. It should be either a user account credential or a service account credential.
        targetPrincipal - the service account to impersonate
        delegates - the chained list of delegates required to grant the final access_token. If set, the sequence of identities must have "Service Account Token Creator" capability granted to the preceding identity. For example, if set to [serviceAccountB, serviceAccountC], the sourceCredential must have the Token Creator role on serviceAccountB. serviceAccountB must have the Token Creator on serviceAccountC. Finally, C must have Token Creator on target_principal. If left unset, sourceCredential must have that role on targetPrincipal.
        scopes - scopes to request during the authorization grant
        lifetime - number of seconds the delegated credential should be valid. By default this value should be at most 3600. However, you can follow these instructions to set up the service account and extend the maximum lifetime to 43200 (12 hours). https://cloud.google.com/iam/docs/creating-short-lived-service-account-credentials#sa-credentials-oauth If the given lifetime is 0, default value 3600 will be used instead when creating the credentials.
        Returns:
        new credentials

      • getAccount

        public String getAccount()
        Returns the email field of the serviceAccount that is being impersonated.
        Specified by:
        getAccount in interface ServiceAccountSigner
        Returns:
        email address of the impersonated service account

      • setTransportFactory

        public void setTransportFactory​(HttpTransportFactory httpTransportFactory)

      • sign

        public byte[] sign​(byte[] toSign)
        Signs the provided bytes using the private key associated with the impersonated service account
        Specified by:
        sign in interface ServiceAccountSigner
        Parameters:
        toSign - bytes to sign
        Returns:
        signed bytes
        Throws:
        ServiceAccountSigner.SigningException - if the attempt to sign the provided bytes failed
        See Also:
        Blob Signing

      • createScoped

        public GoogleCredentials createScoped​(Collection<String> scopes)
        Description copied from class: GoogleCredentials
        If the credentials support scopes, creates a copy of the identity with the specified scopes; otherwise, returns the same instance.
        Overrides:
        createScoped in class GoogleCredentials
        Parameters:
        scopes - Collection of scopes to request.
        Returns:
        GoogleCredentials with requested scopes.

      • createWithCustomCalendar

        public ImpersonatedCredentials createWithCustomCalendar​(Calendar calendar)
        Clones the impersonated credentials with a new calendar.
        Parameters:
        calendar - the calendar that will be used by the new ImpersonatedCredentials instance when parsing the received expiration time of the refreshed access token
        Returns:
        the cloned impersonated credentials with the given custom calendar

      • refreshAccessToken

        public AccessToken refreshAccessToken()
                               throws IOException
        Description copied from class: OAuth2Credentials
        Method to refresh the access token according to the specific type of credentials.

        Throws IllegalStateException if not overridden since direct use of OAuth2Credentials is only for temporary or non-refreshing access tokens.

        Overrides:
        refreshAccessToken in class OAuth2Credentials
        Returns:
        never
        Throws:
        IOException

      • idTokenWithAudience

        public IdToken idTokenWithAudience​(String targetAudience,
                                   List<IdTokenProvider.Option> options)
                            throws IOException
        Returns an IdToken for the current Credential.
        Specified by:
        idTokenWithAudience in interface IdTokenProvider
        Parameters:
        targetAudience - the audience field for the issued ID token
        options - credential specific options for for the token. For example, an ID token for an ImpersonatedCredentials can return the email address within the token claims if "ImpersonatedCredentials.INCLUDE_EMAIL" is provided as a list option.
        Only one option value is supported: "ImpersonatedCredentials.INCLUDE_EMAIL" If no options are set, the default excludes the "includeEmail" attribute in the API request.
        Returns:
        IdToken object which includes the raw id_token, expiration, and audience
        Throws:
        IOException - if the attempt to get an ID token failed