docs(samples): Convert tightly coupled local variable involved options inside of method into method arguments (#393)

As of the current version we can see that more options related to argument
are written inside of the test instead of included as arguments, so I think
as this is tightly coupled with argument, it will be better to pass it as well.

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Fixes #394 ☕️

Author: irvifa

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

@@ -34,10 +34,15 @@ public static void runCreatePartitionedTable() {
     // TODO(developer): Replace these variables before running the sample.
     String datasetName = "MY_DATASET_NAME";
     String tableName = "MY_TABLE_NAME";
-    createPartitionedTable(datasetName, tableName);
+    Schema schema =
+            Schema.of(
+                    Field.of("stringField", StandardSQLTypeName.STRING),
+                    Field.of("booleanField", StandardSQLTypeName.BOOL),
+                    Field.of("dateField", StandardSQLTypeName.DATE));
+    createPartitionedTable(datasetName, tableName, schema);
   }
 
-  public static void createPartitionedTable(String datasetName, String tableName) {
+  public static void createPartitionedTable(String datasetName, String tableName, Schema schema) {
     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.
@@ -47,12 +52,6 @@ public static void createPartitionedTable(String datasetName, String tableName)
 
       TimePartitioning partitioning = TimePartitioning.of(TimePartitioning.Type.DAY);
 
-      Schema schema =
-          Schema.of(
-              Field.of("stringField", StandardSQLTypeName.STRING),
-              Field.of("booleanField", StandardSQLTypeName.BOOL),
-              Field.of("dateField", StandardSQLTypeName.DATE));
-
       StandardTableDefinition tableDefinition =
           StandardTableDefinition.newBuilder()
               .setSchema(schema)

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

@@ -35,12 +35,19 @@ public static void runExtractTableToJson() {
     String tableName = "shakespeare";
     String bucketName = "my-bucket";
     String destinationUri = "gs://" + bucketName + "/path/to/file";
-    extractTableToJson(projectId, datasetName, tableName, destinationUri);
+    // For more information on export formats available see:
+    // https://cloud.google.com/bigquery/docs/exporting-data#export_formats_and_compression_types
+    // For more information on Job see:
+    // https://googleapis.dev/java/google-cloud-clients/latest/index.html?com/google/cloud/bigquery/package-summary.html
+
+    String dataFormat = "CSV";
+    extractTableToJson(projectId, datasetName, tableName, destinationUri, dataFormat);
   }
 
   // Exports datasetName:tableName to destinationUri as raw CSV
   public static void extractTableToJson(
-      String projectId, String datasetName, String tableName, String destinationUri) {
+      String projectId, String datasetName, String tableName, String destinationUri,
+      String dataFormat) {
     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.
@@ -49,11 +56,7 @@ public static void extractTableToJson(
       TableId tableId = TableId.of(projectId, datasetName, tableName);
       Table table = bigquery.getTable(tableId);
 
-      // For more information on export formats available see:
-      // https://cloud.google.com/bigquery/docs/exporting-data#export_formats_and_compression_types
-      // 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 = table.extract("CSV", destinationUri);
+      Job job = table.extract(dataFormat, destinationUri);
 
       // Blocks until this job completes its execution, either failing or succeeding.
       Job completedJob =
@@ -68,7 +71,7 @@ public static void extractTableToJson(
             "BigQuery was unable to extract due to an error: \n" + job.getStatus().getError());
         return;
       }
-      System.out.println("Table export successful. Check in GCS bucket for the CSV file.");
+      System.out.println("Table export successful. Check in GCS bucket for the " + dataFormat + " file.");
     } catch (BigQueryException | InterruptedException e) {
       System.out.println("Table extraction job was interrupted. \n" + e.toString());
     }

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

@@ -41,10 +41,11 @@ public static void runLoadLocalFile() throws IOException, InterruptedException {
     String datasetName = "MY_DATASET_NAME";
     String tableName = "MY_TABLE_NAME";
     Path csvPath = FileSystems.getDefault().getPath(".", "my-data.csv");
-    loadLocalFile(datasetName, tableName, csvPath);
+    loadLocalFile(datasetName, tableName, csvPath, FormatOptions.csv());
   }
 
-  public static void loadLocalFile(String datasetName, String tableName, Path csvPath)
+  public static void loadLocalFile(String datasetName, String tableName, Path csvPath,
+                                   FormatOptions formatOptions)
       throws IOException, InterruptedException {
     try {
       // Initialize client that will be used to send requests. This client only needs to be created
@@ -54,7 +55,7 @@ public static void loadLocalFile(String datasetName, String tableName, Path csvP
 
       WriteChannelConfiguration writeChannelConfiguration =
           WriteChannelConfiguration.newBuilder(tableId)
-              .setFormatOptions(FormatOptions.csv())
+              .setFormatOptions(formatOptions)
               .build();
 
       // The location and JobName must be specified; other fields can be auto-detected.

samples/snippets/src/test/java/com/example/bigquery/CreatePartitionedTableIT.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 org.junit.After;
@@ -58,8 +61,13 @@ public void tearDown() {
   @Test
   public void testCreatePartitionedTable() {
     String tableName = "MY_PARTITIONED_TABLE";
+    Schema schema =
+            Schema.of(
+                    Field.of("stringField", StandardSQLTypeName.STRING),
+                    Field.of("booleanField", StandardSQLTypeName.BOOL),
+                    Field.of("dateField", StandardSQLTypeName.DATE));
 
-    CreatePartitionedTable.createPartitionedTable(BIGQUERY_DATASET_NAME, tableName);
+    CreatePartitionedTable.createPartitionedTable(BIGQUERY_DATASET_NAME, tableName, schema);
 
     assertThat(bout.toString()).contains("Partitioned table created successfully");
 

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

@@ -61,10 +61,12 @@ public void testExtractTableToJson() {
     String datasetName = "samples";
     String tableName = "shakespeare";
     String destinationUri = "gs://" + GCS_BUCKET + "/extractTest.csv";
+    String dataFormat = "CSV";
 
     // Extract table content to GCS in CSV format
-    ExtractTableToJson.extractTableToJson(projectId, datasetName, tableName, destinationUri);
+    ExtractTableToJson.extractTableToJson(projectId, datasetName, tableName, destinationUri,
+            dataFormat);
     assertThat(bout.toString())
-        .contains("Table export successful. Check in GCS bucket for the CSV file.");
+        .contains("Table export successful. Check in GCS bucket for the " + dataFormat + " file.");
   }
 }

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

@@ -20,6 +20,7 @@
 import static junit.framework.TestCase.assertNotNull;
 
 import com.google.cloud.bigquery.Field;
+import com.google.cloud.bigquery.FormatOptions;
 import com.google.cloud.bigquery.LegacySQLTypeName;
 import com.google.cloud.bigquery.Schema;
 import java.io.ByteArrayOutputStream;
@@ -76,7 +77,7 @@ public void loadLocalFile() throws IOException, InterruptedException {
 
     Path csvPath = FileSystems.getDefault().getPath("src/test/resources", "bigquery_noheader.csv");
 
-    LoadLocalFile.loadLocalFile(BIGQUERY_DATASET_NAME, tableName, csvPath);
+    LoadLocalFile.loadLocalFile(BIGQUERY_DATASET_NAME, tableName, csvPath, FormatOptions.csv());
 
     assertThat(bout.toString()).contains("Successfully loaded");