docs(samples): added copy table and accompanying test (#414)

Author: ejdarrow

samples/snippets/src/main/java/com/example/bigquery/CopyTable.java

@@ -0,0 +1,78 @@
+/*
+ * 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.bigquery;
+
+// [START bigquery_copy_table]
+import com.google.cloud.bigquery.BigQuery;
+import com.google.cloud.bigquery.BigQueryException;
+import com.google.cloud.bigquery.BigQueryOptions;
+import com.google.cloud.bigquery.CopyJobConfiguration;
+import com.google.cloud.bigquery.Job;
+import com.google.cloud.bigquery.JobInfo;
+import com.google.cloud.bigquery.TableId;
+
+public class CopyTable {
+
+ public static void runCopyTable() {
+ // TODO(developer): Replace these variables before running the sample.
+ String destinationDatasetName = "MY_DESTINATION_DATASET_NAME";
+ String destinationTableId = "MY_DESTINATION_TABLE_NAME";
+ String sourceDatasetName = "MY_SOURCE_DATASET_NAME";
+ String sourceTableId = "MY_SOURCE_TABLE_NAME";
+
+ copyTable(sourceDatasetName, sourceTableId, destinationDatasetName, destinationTableId);
+ }
+
+ public static void copyTable(String sourceDatasetName, String sourceTableId,
+ String destinationDatasetName, String destinationTableId) {
+ 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.
+ BigQuery bigquery = BigQueryOptions.getDefaultInstance().getService();
+
+ TableId sourceTable = TableId.of(sourceDatasetName, sourceTableId);
+ TableId destinationTable = TableId.of(destinationDatasetName, destinationTableId);
+
+ // For more information on CopyJobConfiguration see:
+ // https://googleapis.dev/java/google-cloud-clients/latest/com/google/cloud/bigquery/JobConfiguration.html
+ CopyJobConfiguration configuration =
+ CopyJobConfiguration.newBuilder(
+ destinationTable,
+ sourceTable
+ ).build();
+
+ // For more information on Job see:
+ // https://googleapis.dev/java/google-cloud-clients/latest/index.html?com/google/cloud/bigquery/package-summary.html
+ Job job = bigquery.create(JobInfo.of(configuration));
+
+ // Blocks until this job completes its execution, either failing or succeeding.
+ Job completedJob = job.waitFor();
+ if (completedJob == null) {
+ System.out.println("Job not executed since it no longer exists.");
+ return;
+ } else if (completedJob.getStatus().getError() != null) {
+ System.out.println(
+ "BigQuery was unable to copy table due to an error: \n" + job.getStatus().getError());
+ return;
+ }
+ System.out.println("Table copied successfully.");
+ } catch (BigQueryException | InterruptedException e) {
+ System.out.println("Table copying job was interrupted. \n" + e.toString());
+ }
+ }
+}
+// [END bigquery_copy_table]

samples/snippets/src/test/java/com/example/bigquery/CopyTableIT.java

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+/*
+ * 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.bigquery;
+
+import static com.google.common.truth.Truth.assertThat;
+import static junit.framework.TestCase.assertNotNull;
+
+import com.google.cloud.bigquery.Field;
+import com.google.cloud.bigquery.Schema;
+import com.google.cloud.bigquery.StandardSQLTypeName;
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+import java.util.UUID;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+public class CopyTableIT {
+ private ByteArrayOutputStream bout;
+ private PrintStream out;
+
+ private static final String BIGQUERY_DATASET_NAME = System.getenv("BIGQUERY_DATASET_NAME");
+
+ private static void requireEnvVar(String varName) {
+ assertNotNull(
+ "Environment variable " + varName + " is required to perform these tests.",
+ System.getenv(varName));
+ }
+
+ @BeforeClass
+ public static void checkRequirements() {
+ requireEnvVar("BIGQUERY_DATASET_NAME");
+ }
+
+ @Before
+ public void setUp() throws Exception {
+ bout = new ByteArrayOutputStream();
+ out = new PrintStream(bout);
+ System.setOut(out);
+ }
+
+ @After
+ public void tearDown() {
+ System.setOut(null);
+ }
+
+ @Test
+ public void testCopyTable() {
+ // Create a new destination and source table for each test since existing table cannot be overwritten
+ String generatedDestTableName = "gcloud_test_table_temp_" +
+ UUID.randomUUID().toString().replace('-', '_');
+ String generatedSourceTableName = "gcloud_test_table_temp_" +
+ UUID.randomUUID().toString().replace('-', '_');
+
+ //Adding an arbitrary table schema so we aren't copying nothing.
+ Schema schema =
+ Schema.of(
+ Field.of("stringField", StandardSQLTypeName.STRING),
+ Field.of("booleanField", StandardSQLTypeName.BOOL));
+
+ CreateTable.createTable(BIGQUERY_DATASET_NAME, generatedDestTableName, schema);
+ CreateTable.createTable(BIGQUERY_DATASET_NAME, generatedSourceTableName, schema);
+
+ CopyTable.copyTable(BIGQUERY_DATASET_NAME, generatedSourceTableName,
+ BIGQUERY_DATASET_NAME, generatedDestTableName);
+ assertThat(bout.toString()).contains("Table copied successfully.");
+
+ // Clean up
+ DeleteTable.deleteTable(BIGQUERY_DATASET_NAME, generatedDestTableName);
+ DeleteTable.deleteTable(BIGQUERY_DATASET_NAME, generatedSourceTableName);
+ }
+}