Update a dataset's access controls.

## Code sample

### Go


Before trying this sample, follow the Go setup instructions in the
[BigQuery quickstart using
client libraries](https://docs.cloud.google.com/bigquery/docs/quickstarts/quickstart-client-libraries).


For more information, see the
[BigQuery Go API
reference documentation](https://godoc.org/cloud.google.com/go/bigquery).


To authenticate to BigQuery, set up Application Default Credentials.
For more information, see

[Set up authentication for client libraries](https://docs.cloud.google.com/bigquery/docs/authentication#client-libs).

    import (
    	"context"
    	"fmt"

    	"cloud.google.com/go/bigquery"
    )

    // updateDatasetAccessControl demonstrates how the access control policy of a dataset
    // can be amended by adding an additional entry corresponding to a specific user identity.
    func updateDatasetAccessControl(projectID, datasetID string) error {
    	// projectID := "my-project-id"
    	// datasetID := "mydataset"
    	ctx := context.Background()
    	client, err := bigquery.NewClient(ctx, projectID)
    	if err != nil {
    		return fmt.Errorf("bigquery.NewClient: %w", err)
    	}
    	defer client.Close()

    	ds := client.Dataset(datasetID)
    	meta, err := ds.Metadata(ctx)
    	if err != nil {
    		return err
    	}
    	// Append a new access control entry to the existing access list.
    	update := bigquery.https://docs.cloud.google.com/go/docs/reference/cloud.google.com/go/bigquery/latest/index.html#cloud_google_com_go_bigquery_DatasetMetadataToUpdate{
    		Access: append(meta.Access, &bigquery.https://docs.cloud.google.com/go/docs/reference/cloud.google.com/go/bigquery/latest/index.html#cloud_google_com_go_bigquery_AccessEntry{
    			Role:       bigquery.https://docs.cloud.google.com/go/docs/reference/cloud.google.com/go/bigquery/latest/index.html#cloud_google_com_go_bigquery_OwnerRole_ReaderRole_WriterRole,
    			EntityType: bigquery.https://docs.cloud.google.com/go/docs/reference/cloud.google.com/go/bigquery/latest/index.html#cloud_google_com_go_bigquery_DomainEntity_GroupEmailEntity_UserEmailEntity_SpecialGroupEntity_ViewEntity_IAMMemberEntity_RoutineEntity_DatasetEntity,
    			Entity:     "sample.bigquery.dev@gmail.com"},
    		),
    	}

    	// Leverage the ETag for the update to assert there's been no modifications to the
    	// dataset since the metadata was originally read.
    	if _, err := ds.Update(ctx, update, meta.ETag); err != nil {
    		return err
    	}
    	return nil
    }

### Java


Before trying this sample, follow the Java setup instructions in the
[BigQuery quickstart using
client libraries](https://docs.cloud.google.com/bigquery/docs/quickstarts/quickstart-client-libraries).


For more information, see the
[BigQuery Java API
reference documentation](https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/overview).


To authenticate to BigQuery, set up Application Default Credentials.
For more information, see

[Set up authentication for client libraries](https://docs.cloud.google.com/bigquery/docs/authentication#client-libs).

    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.html.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.Role.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.html.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.User.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryException.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryOptions.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Dataset.html;
    import java.util.ArrayList;

    public class UpdateDatasetAccess {

      public static void main(String[] args) {
        // TODO(developer): Replace these variables before running the sample.
        String datasetName = "MY_DATASET_NAME";
        // Create a new ACL granting the READER role to "sample.bigquery.dev@gmail.com"
        // For more information on the types of ACLs available see:
        // https://cloud.google.com/storage/docs/access-control/lists
        https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.html newEntry = https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.html.of(new https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.User.html("sample.bigquery.dev@gmail.com"), https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.Role.html.READER);

        updateDatasetAccess(datasetName, newEntry);
      }

      public static void updateDatasetAccess(String datasetName, https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Acl.html newEntry) {
        try {
          // Initialize client that will be used to send requests. This client only needs to be created
          // once, and can be reused for multiple requests.
          https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html bigquery = https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryOptions.html.getDefaultInstance().getService();

          https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.Dataset.html dataset = bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html#com_google_cloud_bigquery_BigQuery_getDataset_com_google_cloud_bigquery_DatasetId_com_google_cloud_bigquery_BigQuery_DatasetOption____(datasetName);

          // Get a copy of the ACLs list from the dataset and append the new entry
          ArrayList<Acl> acls = new ArrayList<>(dataset.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.DatasetInfo.html#com_google_cloud_bigquery_DatasetInfo_getAcl__());
          acls.add(newEntry);

          bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html#com_google_cloud_bigquery_BigQuery_update_com_google_cloud_bigquery_DatasetInfo_com_google_cloud_bigquery_BigQuery_DatasetOption____(dataset.toBuilder().setAcl(acls).build());
          System.out.println("Dataset Access Control updated successfully");
        } catch (https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryException.html e) {
          System.out.println("Dataset Access control was not updated \n" + e.toString());
        }
      }
    }

### Python


Before trying this sample, follow the Python setup instructions in the
[BigQuery quickstart using
client libraries](https://docs.cloud.google.com/bigquery/docs/quickstarts/quickstart-client-libraries).


For more information, see the
[BigQuery Python API
reference documentation](https://docs.cloud.google.com/python/docs/reference/bigquery/latest).


To authenticate to BigQuery, set up Application Default Credentials.
For more information, see

[Set up authentication for client libraries](https://docs.cloud.google.com/bigquery/docs/authentication#client-libs).


    # TODO(developer): Set dataset_id to the ID of the dataset to fetch.
    dataset_id = "your-project.your_dataset"

    # TODO(developer): Set entity_id to the ID of the email or group from whom
    # you are adding access. Alternatively, to the JSON REST API representation
    # of the entity, such as a view's table reference.
    entity_id = "user-or-group-to-add@example.com"

    from google.cloud.bigquery.enums import https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.enums.EntityTypes.html

    # TODO(developer): Set entity_type to the type of entity you are granting access to.
    # Common types include:
    #
    # * "userByEmail" -- A single user or service account. For example "fred@example.com"
    # * "groupByEmail" -- A group of users. For example "example@googlegroups.com"
    # * "view" -- An authorized view. For example
    #       {"projectId": "p", "datasetId": "d", "tableId": "v"}
    #
    # For a complete reference, see the REST API reference documentation:
    # https://cloud.google.com/bigquery/docs/reference/rest/v2/datasets#Dataset.FIELDS.access
    entity_type = https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.enums.EntityTypes.html.GROUP_BY_EMAIL

    # TODO(developer): Set role to a one of the "Basic roles for datasets"
    # described here:
    # https://cloud.google.com/bigquery/docs/access-control-basic-roles#dataset-basic-roles
    role = "READER"

    from google.cloud import https://docs.cloud.google.com/python/docs/reference/bigquery/latest

    # Construct a BigQuery client object.
    client = https://docs.cloud.google.com/python/docs/reference/bigquery/latest.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.client.Client.html()

    dataset = client.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.client.Client.html#google_cloud_bigquery_client_Client_get_dataset(dataset_id)  # Make an API request.

    entries = list(dataset.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.dataset.Dataset.html#google_cloud_bigquery_dataset_Dataset_access_entries)
    entries.append(
        https://docs.cloud.google.com/python/docs/reference/bigquery/latest.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.dataset.AccessEntry.html(
            role=role,
            entity_type=entity_type,
            entity_id=entity_id,
        )
    )
    dataset.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.dataset.Dataset.html#google_cloud_bigquery_dataset_Dataset_access_entries = entries

    dataset = client.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.client.Client.html#google_cloud_bigquery_client_Client_update_dataset(dataset, ["access_entries"])  # Make an API request.

    full_dataset_id = "{}.{}".format(dataset.project, dataset.dataset_id)
    print(
        "Updated dataset '{}' with modified user permissions.".format(full_dataset_id)
    )

## What's next


To search and filter code samples for other Google Cloud products, see the
[Google Cloud sample browser](https://docs.cloud.google.com/docs/samples?product=bigquery).