Class ImpersonatedCredentials (1.28.0) 

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);

Inheritance

Object > Credentials > OAuth2Credentials > GoogleCredentials > ImpersonatedCredentials

Static Methods

create(GoogleCredentials sourceCredentials, String targetPrincipal, List<String> delegates, List<String> scopes, int lifetime)

public static ImpersonatedCredentials create(GoogleCredentials sourceCredentials, String targetPrincipal, List<String> delegates, List<String> scopes, int lifetime)
Parameters
Name Description
sourceCredentials GoogleCredentials

the source credential used to acquire the impersonated credentials. It should be either a user account credential or a service account credential.
targetPrincipal String

the service account to impersonate
delegates List<String>

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 List<String>

scopes to request during the authorization grant
lifetime int

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
Type Description
ImpersonatedCredentials

new credentials

create(GoogleCredentials sourceCredentials, String targetPrincipal, List<String> delegates, List<String> scopes, int lifetime, HttpTransportFactory transportFactory)

public static ImpersonatedCredentials create(GoogleCredentials sourceCredentials, String targetPrincipal, List<String> delegates, List<String> scopes, int lifetime, HttpTransportFactory transportFactory)
Parameters
Name Description
sourceCredentials GoogleCredentials

the source credential used to acquire the impersonated credentials. It should be either a user account credential or a service account credential.
targetPrincipal String

the service account to impersonate
delegates List<String>

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 List<String>

scopes to request during the authorization grant
lifetime int

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 HttpTransportFactory

HTTP transport factory that creates the transport used to get access tokens
Returns
Type Description
ImpersonatedCredentials

new credentials

create(GoogleCredentials sourceCredentials, String targetPrincipal, List<String> delegates, List<String> scopes, int lifetime, HttpTransportFactory transportFactory, String quotaProjectId)

public static ImpersonatedCredentials create(GoogleCredentials sourceCredentials, String targetPrincipal, List<String> delegates, List<String> scopes, int lifetime, HttpTransportFactory transportFactory, String quotaProjectId)
Parameters
Name Description
sourceCredentials GoogleCredentials

the source credential used to acquire the impersonated credentials. It should be either a user account credential or a service account credential.
targetPrincipal String

the service account to impersonate
delegates List<String>

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 List<String>

scopes to request during the authorization grant
lifetime int

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 HttpTransportFactory

HTTP transport factory that creates the transport used to get access tokens.
quotaProjectId String

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
Type Description
ImpersonatedCredentials

new credentials

create(GoogleCredentials sourceCredentials, String targetPrincipal, List<String> delegates, List<String> scopes, int lifetime, HttpTransportFactory transportFactory, String quotaProjectId, String iamEndpointOverride)

public static ImpersonatedCredentials create(GoogleCredentials sourceCredentials, String targetPrincipal, List<String> delegates, List<String> scopes, int lifetime, HttpTransportFactory transportFactory, String quotaProjectId, String iamEndpointOverride)
Parameters
Name Description
sourceCredentials GoogleCredentials

the source credential used to acquire the impersonated credentials. It should be either a user account credential or a service account credential.
targetPrincipal String

the service account to impersonate
delegates List<String>

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 List<String>

scopes to request during the authorization grant
lifetime int

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 HttpTransportFactory

HTTP transport factory that creates the transport used to get access tokens.
quotaProjectId String

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 String

The full IAM endpoint override with the target_principal embedded. This is useful when supporting impersonation with regional endpoints.
Returns
Type Description
ImpersonatedCredentials

new credentials

newBuilder()

public static ImpersonatedCredentials.Builder newBuilder()
Returns
Type Description
ImpersonatedCredentials.Builder

Methods

createScoped(Collection<String> scopes)

public GoogleCredentials createScoped(Collection<String> scopes)

If the credentials support scopes, creates a copy of the identity with the specified scopes, invalidates the existing scoped access token; otherwise, return the same instance.

Parameter
Name Description
scopes Collection<String>
Returns
Type Description
GoogleCredentials
Overrides

createScopedRequired()

public boolean createScopedRequired()

Indicates whether the credentials require scopes to be specified via a call to GoogleCredentials#createScoped before use.

Returns
Type Description
boolean
Overrides

createWithCustomCalendar(Calendar calendar)

public ImpersonatedCredentials createWithCustomCalendar(Calendar calendar)

Clones the impersonated credentials with a new calendar.

Parameter
Name Description
calendar Calendar

the calendar that will be used by the new ImpersonatedCredentials instance when parsing the received expiration time of the refreshed access token
Returns
Type Description
ImpersonatedCredentials

the cloned impersonated credentials with the given custom calendar

equals(Object obj)

public boolean equals(Object obj)
Parameter
Name Description
obj Object
Returns
Type Description
boolean
Overrides

getAccount()

public String getAccount()

Returns the email field of the serviceAccount that is being impersonated.

Returns
Type Description
String

email address of the impersonated service account

getMetricsCredentialType()

public CredentialTypeForMetrics getMetricsCredentialType()

Gets the credential type used for internal metrics header.

The default is CredentialTypeForMetrics.DO_NOT_SEND. For a credential that is established to track for metrics, this default should be overridden.

Returns
Type Description
CredentialTypeForMetrics
Overrides

getSourceCredentials()

public GoogleCredentials getSourceCredentials()
Returns
Type Description
GoogleCredentials

hashCode()

public int hashCode()
Returns
Type Description
int
Overrides

idTokenWithAudience(String targetAudience, List<IdTokenProvider.Option> options)

public IdToken idTokenWithAudience(String targetAudience, List<IdTokenProvider.Option> options)

Returns an IdToken for the current Credential.

Parameters
Name Description
targetAudience String

the audience field for the issued ID token
options List<Option>

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
Type Description
IdToken

IdToken object which includes the raw id_token, expiration, and audience
Exceptions
Type Description
IOException

if the attempt to get an ID token failed

refreshAccessToken()

public AccessToken refreshAccessToken()

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.

Returns
Type Description
AccessToken
Overrides
Exceptions
Type Description
IOException

setTransportFactory(HttpTransportFactory httpTransportFactory)

public void setTransportFactory(HttpTransportFactory httpTransportFactory)
Parameter
Name Description
httpTransportFactory HttpTransportFactory

sign(byte[] toSign)

public byte[] sign(byte[] toSign)

Signs the provided bytes using the private key associated with the impersonated service account See Also: Blob Signing

Parameter
Name Description
toSign byte[]

bytes to sign
Returns
Type Description
byte[]

signed bytes

toBuilder()

public ImpersonatedCredentials.Builder toBuilder()
Returns
Type Description
ImpersonatedCredentials.Builder
Overrides

toString()

public String toString()
Returns
Type Description
String
Overrides