feat: Allow passing autodetect_schema on table update (#2661)

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-  Didn't open an issue because this seems trivial, happy to adapt if necessary.
- [x ] Ensure the tests and linter pass (mvn test verify
- [x ] Code coverage does not decrease (if any source code was changed)
- [x ] Appropriate docs were updated (if necessary)

Author: emkornfield

google-cloud-bigquery/src/main/java/com/google/cloud/bigquery/BigQuery.java

@@ -376,6 +376,14 @@ public static TableOption fields(TableField... fields) {
       return new TableOption(
           BigQueryRpc.Option.FIELDS, Helper.selector(TableField.REQUIRED_FIELDS, fields));
     }
+
+    /**
+     * Returns an option to specify the schema of the table (only applicable for external tables)
+     * should be autodetected when updating the table from the underlying source.
+     */
+    public static TableOption autodetectSchema(boolean autodetect) {
+      return new TableOption(BigQueryRpc.Option.AUTODETECT_SCHEMA, autodetect);
+    }
   }
 
   /*  Class for specifying IAM options. */

google-cloud-bigquery/src/main/java/com/google/cloud/bigquery/spi/v2/BigQueryRpc.java

@@ -46,6 +46,7 @@ enum Option {
     DELETE_CONTENTS("deleteContents"),
     ALL_DATASETS("all"),
     ALL_USERS("allUsers"),
+    AUTODETECT_SCHEMA("autodetectSchema"),
     LABEL_FILTER("filter"),
     MIN_CREATION_TIME("minCreationTime"),
     MAX_CREATION_TIME("maxCreationTime"),

google-cloud-bigquery/src/main/java/com/google/cloud/bigquery/spi/v2/HttpBigQueryRpc.java

@@ -279,6 +279,7 @@ public Table patch(Table table, Map<Option, ?> options) {
           .patch(reference.getProjectId(), reference.getDatasetId(), reference.getTableId(), table)
           .setPrettyPrint(false)
           .setFields(Option.FIELDS.getString(options))
+          .setAutodetectSchema(BigQueryRpc.Option.AUTODETECT_SCHEMA.getBoolean(options))
           .execute();
     } catch (IOException ex) {
       throw translate(ex);

google-cloud-bigquery/src/test/java/com/google/cloud/bigquery/BigQueryImplTest.java

@@ -1260,6 +1260,24 @@ public void testUpdateTableWithSelectedFields() {
         .patch(eq(updatedTableInfoWithProject.toPb()), capturedOptions.capture());
   }
 
+  @Test
+  public void testUpdateTableWithAutoDetectSchema() {
+    TableInfo updatedTableInfo = TABLE_INFO.toBuilder().setDescription("newDescription").build();
+    TableInfo updatedTableInfoWithProject =
+        TABLE_INFO_WITH_PROJECT.toBuilder().setDescription("newDescription").build();
+    when(bigqueryRpcMock.patch(eq(updatedTableInfoWithProject.toPb()), capturedOptions.capture()))
+        .thenReturn(updatedTableInfoWithProject.toPb());
+    bigquery = options.getService();
+    Table table = bigquery.update(updatedTableInfo, BigQuery.TableOption.autodetectSchema(true));
+    Boolean selector =
+        (Boolean) capturedOptions.getValue().get(BigQueryRpc.Option.AUTODETECT_SCHEMA);
+    assertTrue(selector);
+    assertEquals(
+        new Table(bigquery, new TableInfo.BuilderImpl(updatedTableInfoWithProject)), table);
+    verify(bigqueryRpcMock)
+        .patch(eq(updatedTableInfoWithProject.toPb()), capturedOptions.capture());
+  }
+
   @Test
   public void testInsertAllWithRowIdShouldRetry() {
     Map<String, Object> row1 = ImmutableMap.<String, Object>of("field", "value1");

google-cloud-bigquery/src/test/java/com/google/cloud/bigquery/it/ITBigQueryTest.java

@@ -1566,6 +1566,45 @@ public void testSetPermExternalTableSchema() {
     assertTrue(remoteTable.delete());
   }
 
+  @Test
+  public void testUpdatePermExternableTableWithAutodetectSchemaUpdatesSchema() {
+    String tableName = "test_create_external_table_perm_with_auto_detect";
+    TableId tableId = TableId.of(DATASET, tableName);
+    Schema setSchema = Schema.of(TIMESTAMP_FIELD_SCHEMA, STRING_FIELD_SCHEMA);
+
+    ExternalTableDefinition externalTableDefinition =
+        ExternalTableDefinition.newBuilder(
+                "gs://" + BUCKET + "/" + JSON_LOAD_FILE, FormatOptions.json())
+            .setSchema(setSchema)
+            .build();
+    TableInfo tableInfo = TableInfo.of(tableId, externalTableDefinition);
+    Table createdTable = bigquery.create(tableInfo);
+
+    assertNotNull(createdTable);
+    assertEquals(DATASET, createdTable.getTableId().getDataset());
+    assertEquals(tableName, createdTable.getTableId().getTable());
+    Table remoteTable = bigquery.getTable(DATASET, tableName);
+    assertNotNull(remoteTable);
+    assertEquals(setSchema, remoteTable.getDefinition().getSchema());
+
+    Table updatedTable =
+        bigquery.update(
+            createdTable
+                .toBuilder()
+                .setDefinition(
+                    ((ExternalTableDefinition) createdTable.getDefinition())
+                        .toBuilder()
+                        .setSchema(null)
+                        .setAutodetect(true)
+                        .build())
+                .build(),
+            BigQuery.TableOption.autodetectSchema(true));
+    // Schema should change.
+    assertTrue(!updatedTable.getDefinition().getSchema().equals(setSchema));
+
+    assertTrue(remoteTable.delete());
+  }
+
   @Test
   public void testCreateViewTable() throws InterruptedException {
     String tableName = "test_create_view_table";