Utilisez le rédacteur de flux JSON pour ajouter des enregistrements validés.
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Exemple de code
Java
Avant d'essayer cet exemple, suivez les instructions de configuration pour Java du guide de démarrage rapide de BigQuery : Utiliser les bibliothèques clientes. Pour en savoir plus, consultez la documentation de référence de l'API BigQuery pour Java.
Pour vous authentifier auprès de BigQuery, configurez le service Identifiants par défaut de l'application. Pour en savoir plus, consultez la page Configurer l'authentification pour les bibliothèques clientes.
import com.google.api.core.ApiFuture;
import com.google.api.core.ApiFutureCallback;
import com.google.api.core.ApiFutures;
import com.google.api.gax.retrying.RetrySettings;
import com.google.cloud.bigquery.storage.v1.AppendRowsResponse;
import com.google.cloud.bigquery.storage.v1.BigQueryWriteClient;
import com.google.cloud.bigquery.storage.v1.CreateWriteStreamRequest;
import com.google.cloud.bigquery.storage.v1.Exceptions;
import com.google.cloud.bigquery.storage.v1.Exceptions.StorageException;
import com.google.cloud.bigquery.storage.v1.FinalizeWriteStreamResponse;
import com.google.cloud.bigquery.storage.v1.JsonStreamWriter;
import com.google.cloud.bigquery.storage.v1.TableName;
import com.google.cloud.bigquery.storage.v1.WriteStream;
import com.google.common.util.concurrent.MoreExecutors;
import com.google.protobuf.Descriptors.DescriptorValidationException;
import java.io.IOException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Phaser;
import javax.annotation.concurrent.GuardedBy;
import org.json.JSONArray;
import org.json.JSONObject;
import org.threeten.bp.Duration;
public class WriteCommittedStream {
public static void runWriteCommittedStream()
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";
writeCommittedStream(projectId, datasetName, tableName);
}
public static void writeCommittedStream(String projectId, String datasetName, String tableName)
throws DescriptorValidationException, InterruptedException, IOException {
BigQueryWriteClient client = BigQueryWriteClient.create();
TableName parentTable = TableName.of(projectId, datasetName, tableName);
DataWriter writer = new DataWriter();
// One time initialization.
writer.initialize(parentTable, client);
try {
// Write two batches of fake data to the stream, each with 10 JSON records. Data may be
// batched up to the maximum request size:
// https://cloud.google.com/bigquery/quotas#write-api-limits
long offset = 0;
for (int i = 0; i < 2; i++) {
// Create a JSON object that is compatible with the table schema.
JSONArray jsonArr = new JSONArray();
for (int j = 0; j < 10; j++) {
JSONObject record = new JSONObject();
record.put("col1", String.format("batch-record %03d-%03d", i, j));
jsonArr.put(record);
}
writer.append(jsonArr, offset);
offset += jsonArr.length();
}
} 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);
}
// Final cleanup for the stream.
writer.cleanup(client);
System.out.println("Appended records successfully.");
}
// A simple wrapper object showing how the stateful stream writer should be used.
private static class DataWriter {
private JsonStreamWriter streamWriter;
// Track the number of in-flight requests to wait for all responses before shutting down.
private final Phaser inflightRequestCount = new Phaser(1);
private final Object lock = new Object();
@GuardedBy("lock")
private RuntimeException error = null;
void initialize(TableName parentTable, BigQueryWriteClient client)
throws IOException, DescriptorValidationException, InterruptedException {
// Initialize a write stream for the specified table.
// For more information on WriteStream.Type, see:
// https://googleapis.dev/java/google-cloud-bigquerystorage/latest/com/google/cloud/bigquery/storage/v1/WriteStream.Type.html
WriteStream stream = WriteStream.newBuilder().setType(WriteStream.Type.COMMITTED).build();
CreateWriteStreamRequest createWriteStreamRequest =
CreateWriteStreamRequest.newBuilder()
.setParent(parentTable.toString())
.setWriteStream(stream)
.build();
WriteStream writeStream = client.createWriteStream(createWriteStreamRequest);
// Configure in-stream automatic retry settings.
// Error codes that are immediately retried:
// * ABORTED, UNAVAILABLE, CANCELLED, INTERNAL, DEADLINE_EXCEEDED
// Error codes that are retried with exponential backoff:
// * RESOURCE_EXHAUSTED
RetrySettings retrySettings =
RetrySettings.newBuilder()
.setInitialRetryDelay(Duration.ofMillis(500))
.setRetryDelayMultiplier(1.1)
.setMaxAttempts(5)
.setMaxRetryDelay(Duration.ofMinutes(1))
.build();
// 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/v1/JsonStreamWriter.html
streamWriter =
JsonStreamWriter.newBuilder(writeStream.getName(), writeStream.getTableSchema(), client)
.setRetrySettings(retrySettings)
.build();
}
public void append(JSONArray data, long offset)
throws DescriptorValidationException, IOException, ExecutionException {
synchronized (this.lock) {
// If earlier appends have failed, we need to reset before continuing.
if (this.error != null) {
throw this.error;
}
}
// Append asynchronously for increased throughput.
ApiFuture<AppendRowsResponse> future = streamWriter.append(data, offset);
ApiFutures.addCallback(
future, new DataWriter.AppendCompleteCallback(this), MoreExecutors.directExecutor());
// Increase the count of in-flight requests.
inflightRequestCount.register();
}
public void cleanup(BigQueryWriteClient client) {
// Wait for all in-flight requests to complete.
inflightRequestCount.arriveAndAwaitAdvance();
// Close the connection to the server.
streamWriter.close();
// Verify that no error occurred in the stream.
synchronized (this.lock) {
if (this.error != null) {
throw this.error;
}
}
// Finalize the stream.
FinalizeWriteStreamResponse finalizeResponse =
client.finalizeWriteStream(streamWriter.getStreamName());
System.out.println("Rows written: " + finalizeResponse.getRowCount());
}
public String getStreamName() {
return streamWriter.getStreamName();
}
static class AppendCompleteCallback implements ApiFutureCallback<AppendRowsResponse> {
private final DataWriter parent;
public AppendCompleteCallback(DataWriter parent) {
this.parent = parent;
}
public void onSuccess(AppendRowsResponse response) {
System.out.format("Append %d success\n", response.getAppendResult().getOffset().getValue());
done();
}
public void onFailure(Throwable throwable) {
synchronized (this.parent.lock) {
if (this.parent.error == null) {
StorageException storageException = Exceptions.toStorageException(throwable);
this.parent.error =
(storageException != null) ? storageException : new RuntimeException(throwable);
}
}
System.out.format("Error: %s\n", throwable.toString());
done();
}
private void done() {
// Reduce the count of in-flight requests.
this.parent.inflightRequestCount.arriveAndDeregister();
}
}
}
}Étapes suivantes
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