| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.beam.sdk.io.gcp.bigquery; |
| |
| import java.io.IOException; |
| import java.util.UUID; |
| import org.apache.beam.sdk.transforms.DoFn; |
| import org.apache.beam.sdk.transforms.windowing.BoundedWindow; |
| import org.apache.beam.sdk.values.KV; |
| import org.apache.beam.sdk.values.ShardedKey; |
| import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.annotations.VisibleForTesting; |
| |
| /** |
| * Fn that tags each table row with a unique id and destination table. To avoid calling |
| * UUID.randomUUID() for each element, which can be costly, a randomUUID is generated only once per |
| * bucket of data. The actual unique id is created by concatenating this randomUUID with a |
| * sequential number. |
| */ |
| @VisibleForTesting |
| class TagWithUniqueIds<ElementT> |
| extends DoFn<KV<ShardedKey<String>, ElementT>, KV<ShardedKey<String>, TableRowInfo>> { |
| private transient String randomUUID; |
| private transient long sequenceNo = 0L; |
| |
| @StartBundle |
| public void startBundle() { |
| randomUUID = UUID.randomUUID().toString(); |
| } |
| |
| /** Tag the input with a unique id. */ |
| @ProcessElement |
| public void processElement(ProcessContext context, BoundedWindow window) throws IOException { |
| String uniqueId = randomUUID + sequenceNo++; |
| // We output on keys 0-50 to ensure that there's enough batching for |
| // BigQuery. |
| context.output( |
| KV.of( |
| context.element().getKey(), new TableRowInfo(context.element().getValue(), uniqueId))); |
| } |
| } |