docs(samples): fix CopyMultipleTables sample IT failure and improve a few other samples (#1817)

* docs(samples): fix CopyMultipleTables sample IT failure and improve a few other samples

Fixes issue: #1805

* 🦉 Updates from OwlBot

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: stephaniewang526

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

@@ -32,25 +32,30 @@ public static void main(String[] args) {
     // TODO(developer): Replace these variables before running the sample.
     String destinationDatasetName = "MY_DATASET_NAME";
     String destinationTableId = "MY_TABLE_NAME";
-    copyMultipleTables(destinationDatasetName, destinationTableId);
+    String sourceTable1Id = "MY_SOURCE_TABLE_1";
+    String sourceTable2Id = "MY_SOURCE_TABLE_2";
+    copyMultipleTables(destinationDatasetName, destinationTableId, sourceTable1Id, sourceTable2Id);
   }
 
-  public static void copyMultipleTables(String destinationDatasetName, String destinationTableId) {
+  public static void copyMultipleTables(
+      String destinationDatasetName,
+      String destinationTableId,
+      String sourceTable1Id,
+      String sourceTable2Id) {
     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 destinationTable = TableId.of(destinationDatasetName, destinationTableId);
+      TableId sourceTable1 = TableId.of(destinationDatasetName, sourceTable1Id);
+      TableId sourceTable2 = TableId.of(destinationDatasetName, sourceTable2Id);
 
       // 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,
-                  Arrays.asList(
-                      TableId.of(destinationDatasetName, "table1"),
-                      TableId.of(destinationDatasetName, "table2")))
+                  destinationTable, Arrays.asList(sourceTable1, sourceTable2))
               .build();
 
       // For more information on Job see:

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

@@ -17,6 +17,8 @@
 package com.example.bigquery;
 
 // [START bigquery_query_external_bigtable_perm]
+
+import com.google.api.client.util.Base64;
 import com.google.cloud.bigquery.BigQuery;
 import com.google.cloud.bigquery.BigQueryException;
 import com.google.cloud.bigquery.BigQueryOptions;
@@ -29,7 +31,6 @@
 import com.google.cloud.bigquery.TableInfo;
 import com.google.cloud.bigquery.TableResult;
 import com.google.common.collect.ImmutableList;
-import org.apache.commons.codec.binary.Base64;
 
 // Sample to queries an external bigtable data source using a permanent table
 public class QueryExternalBigtablePerm {

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

@@ -17,6 +17,8 @@
 package com.example.bigquery;
 
 // [START bigquery_query_external_bigtable_temp]
+
+import com.google.api.client.util.Base64;
 import com.google.cloud.bigquery.BigQuery;
 import com.google.cloud.bigquery.BigQueryException;
 import com.google.cloud.bigquery.BigQueryOptions;
@@ -27,7 +29,6 @@
 import com.google.cloud.bigquery.QueryJobConfiguration;
 import com.google.cloud.bigquery.TableResult;
 import com.google.common.collect.ImmutableList;
-import org.apache.commons.codec.binary.Base64;
 
 // Sample to queries an external bigtable data source using a temporary table
 public class QueryExternalBigtableTemp {

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

@@ -19,6 +19,9 @@
 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;
@@ -32,22 +35,27 @@
 public class CopyMultipleTablesIT {
 
   private final Logger log = Logger.getLogger(this.getClass().getName());
+  private String datasetName;
   private String tableName;
+  private String sourceTable1Name;
+  private String sourceTable2Name;
   private ByteArrayOutputStream bout;
   private PrintStream out;
   private PrintStream originalPrintStream;
 
-  private static final String BIGQUERY_DATASET_NAME = System.getenv("BIGQUERY_DATASET_NAME");
+  private static final String PROJECT_ID = requireEnvVar("GOOGLE_CLOUD_PROJECT");
 
-  private static void requireEnvVar(String varName) {
+  private static String requireEnvVar(String varName) {
+    String value = System.getenv(varName);
     assertNotNull(
         "Environment variable " + varName + " is required to perform these tests.",
         System.getenv(varName));
+    return value;
   }
 
   @BeforeClass
   public static void checkRequirements() {
-    requireEnvVar("BIGQUERY_DATASET_NAME");
+    requireEnvVar("GOOGLE_CLOUD_PROJECT");
   }
 
   @Before
@@ -56,15 +64,30 @@ public void setUp() throws Exception {
     out = new PrintStream(bout);
     originalPrintStream = System.out;
     System.setOut(out);
+
     // Create a new destination table for each test since existing table cannot be overwritten
+    datasetName = "MY_DATASET_NAME_TEST_" + UUID.randomUUID().toString().substring(0, 8);
     tableName = "COPY_MULTIPLE_TABLE_TEST" + UUID.randomUUID().toString().substring(0, 8);
-    CreateTable.createTable(BIGQUERY_DATASET_NAME, tableName, null);
+    sourceTable1Name =
+        "COPY_MULTIPLE_TABLE_SOURCE1_TEST" + UUID.randomUUID().toString().substring(0, 8);
+    sourceTable2Name =
+        "COPY_MULTIPLE_TABLE_SOURCE2_TEST" + UUID.randomUUID().toString().substring(0, 8);
+    CreateDataset.createDataset(datasetName);
+
+    Schema schema =
+        Schema.of(
+            Field.of("timestampField", StandardSQLTypeName.TIMESTAMP),
+            Field.of("stringField", StandardSQLTypeName.STRING),
+            Field.of("booleanField", StandardSQLTypeName.BOOL));
+    CreateTable.createTable(datasetName, tableName, schema);
+    CreateTable.createTable(datasetName, sourceTable1Name, schema);
+    CreateTable.createTable(datasetName, sourceTable2Name, schema);
   }
 
   @After
   public void tearDown() {
     // Clean up
-    DeleteTable.deleteTable(BIGQUERY_DATASET_NAME, tableName);
+    DeleteDataset.deleteDataset(PROJECT_ID, datasetName);
     // restores print statements in the original method
     System.out.flush();
     System.setOut(originalPrintStream);
@@ -73,7 +96,8 @@ public void tearDown() {
 
   @Test
   public void testCopyMultipleTables() {
-    CopyMultipleTables.copyMultipleTables(BIGQUERY_DATASET_NAME, tableName);
+    CopyMultipleTables.copyMultipleTables(
+        datasetName, tableName, sourceTable1Name, sourceTable2Name);
     assertThat(bout.toString()).contains("Table copied successfully.");
   }
 }