WriteToDefaultStream.java

/*
 * Copyright 2020 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.bigquerystorage;

// [START bigquerystorage_jsonstreamwriter_default]
import com.google.api.core.ApiFuture;
import com.google.cloud.bigquery.BigQuery;
import com.google.cloud.bigquery.BigQueryOptions;
import com.google.cloud.bigquery.Schema;
import com.google.cloud.bigquery.Table;
import com.google.cloud.bigquery.storage.v1beta2.AppendRowsResponse;
import com.google.cloud.bigquery.storage.v1beta2.JsonStreamWriter;
import com.google.cloud.bigquery.storage.v1beta2.TableName;
import com.google.protobuf.Descriptors.DescriptorValidationException;
import java.io.IOException;
import java.util.concurrent.ExecutionException;
import org.json.JSONArray;
import org.json.JSONObject;

public class WriteToDefaultStream {

  public static void runWriteToDefaultStream()
      throws DescriptorValidationException, InterruptedException, IOException {
    // TODO(developer): Replace these variables before running the sample.
    String projectId = "MY_PROJECT_ID";
    String datasetName = "MY_DATASET_NAME";
    String tableName = "MY_TABLE_NAME";
    
    writeToDefaultStream(projectId, datasetName, tableName);
  }

  public static void writeToDefaultStream(String projectId, String datasetName, String tableName)
      throws DescriptorValidationException, InterruptedException, IOException {
    BigQuery bigquery = BigQueryOptions.getDefaultInstance().getService();
    Table table = bigquery.getTable(datasetName, tableName);
    TableName parentTable = TableName.of(projectId, datasetName, tableName);
    Schema schema = table.getDefinition().getSchema();

    // Use the JSON stream writer to send records in JSON format.
    // For more information about JsonStreamWriter, see:
    // https://googleapis.dev/java/google-cloud-bigquerystorage/latest/com/google/cloud/bigquery/storage/v1beta2/JstreamWriter.html
    try (JsonStreamWriter writer =
        JsonStreamWriter.newBuilder(parentTable.toString(), schema).createDefaultStream().build()) {
      // Append 10 JSON objects to the stream.
      for (int i = 0; i < 10; i++) {
        // Create a JSON object that is compatible with the table schema.
        JSONObject record = new JSONObject();
        record.put("col1", String.format("record %03d", i));
        JSONArray jsonArr = new JSONArray();
        jsonArr.put(record);

        ApiFuture<AppendRowsResponse> future = writer.append(jsonArr);
        AppendRowsResponse response = future.get();
      }
      System.out.println("Appended records successfully.");
    } catch (ExecutionException e) {
      // If the wrapped exception is a StatusRuntimeException, check the state of the operation.
      // If the state is INTERNAL, CANCELLED, or ABORTED, you can retry. For more information, see:
      // https://grpc.github.io/grpc-java/javadoc/io/grpc/StatusRuntimeException.html
      System.out.println("Failed to append records. \n" + e.toString());
    }
  }
}
// [END bigquerystorage_jsonstreamwriter_default]