Create a scheduled query with a service account

import com.google.api.gax.rpc.ApiException;
import com.google.cloud.bigquery.datatransfer.v1.CreateTransferConfigRequest;
import com.google.cloud.bigquery.datatransfer.v1.DataTransferServiceClient;
import com.google.cloud.bigquery.datatransfer.v1.ProjectName;
import com.google.cloud.bigquery.datatransfer.v1.TransferConfig;
import com.google.protobuf.Struct;
import com.google.protobuf.Value;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

// Sample to create a scheduled query with service account
public class CreateScheduledQueryWithServiceAccount {

  public static void main(String[] args) throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    final String projectId = "MY_PROJECT_ID";
    final String datasetId = "MY_DATASET_ID";
    final String serviceAccount = "MY_SERVICE_ACCOUNT";
    final String query =
        "SELECT CURRENT_TIMESTAMP() as current_time, @run_time as intended_run_time, "
            + "@run_date as intended_run_date, 17 as some_integer";
    Map<String, Value> params = new HashMap<>();
    params.put("query", Value.newBuilder().setStringValue(query).build());
    params.put(
        "destination_table_name_template",
        Value.newBuilder().setStringValue("my_destination_table_{run_date}").build());
    params.put("write_disposition", Value.newBuilder().setStringValue("WRITE_TRUNCATE").build());
    params.put("partitioning_field", Value.newBuilder().build());
    TransferConfig transferConfig =
        TransferConfig.newBuilder()
            .setDestinationDatasetId(datasetId)
            .setDisplayName("Your Scheduled Query Name")
            .setDataSourceId("scheduled_query")
            .setParams(Struct.newBuilder().putAllFields(params).build())
            .setSchedule("every 24 hours")
            .build();
    createScheduledQueryWithServiceAccount(projectId, transferConfig, serviceAccount);
  }

  public static void createScheduledQueryWithServiceAccount(
      String projectId, TransferConfig transferConfig, String serviceAccount) throws IOException {
    try (DataTransferServiceClient dataTransferServiceClient = DataTransferServiceClient.create()) {
      ProjectName parent = ProjectName.of(projectId);
      CreateTransferConfigRequest request =
          CreateTransferConfigRequest.newBuilder()
              .setParent(parent.toString())
              .setTransferConfig(transferConfig)
              .setServiceAccountName(serviceAccount)
              .build();
      TransferConfig config = dataTransferServiceClient.createTransferConfig(request);
      System.out.println(
          "\nScheduled query with service account created successfully :" + config.getName());
    } catch (ApiException ex) {
      System.out.print("\nScheduled query with service account was not created." + ex.toString());
    }
  }
}

from google.cloud import bigquery_datatransfer

transfer_client = bigquery_datatransfer.DataTransferServiceClient()

# The project where the query job runs is the same as the project
# containing the destination dataset.
project_id = "your-project-id"
dataset_id = "your_dataset_id"

# This service account will be used to execute the scheduled queries. Omit
# this request parameter to run the query as the user with the credentials
# associated with this client.
service_account_name = "abcdef-test-sa@abcdef-test.iam.gserviceaccount.com"

# Use standard SQL syntax for the query.
query_string = """
SELECT
  CURRENT_TIMESTAMP() as current_time,
  @run_time as intended_run_time,
  @run_date as intended_run_date,
  17 as some_integer
"""

parent = transfer_client.common_project_path(project_id)

transfer_config = bigquery_datatransfer.TransferConfig(
    destination_dataset_id=dataset_id,
    display_name="Your Scheduled Query Name",
    data_source_id="scheduled_query",
    params={
        "query": query_string,
        "destination_table_name_template": "your_table_{run_date}",
        "write_disposition": "WRITE_TRUNCATE",
        "partitioning_field": "",
    },
    schedule="every 24 hours",
)

transfer_config = transfer_client.create_transfer_config(
    bigquery_datatransfer.CreateTransferConfigRequest(
        parent=parent,
        transfer_config=transfer_config,
        service_account_name=service_account_name,
    )
)

print("Created scheduled query '{}'".format(transfer_config.name))