| /* |
| * 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.testutils.metrics; |
| |
| import org.apache.beam.sdk.metrics.Counter; |
| import org.apache.beam.sdk.metrics.Metrics; |
| import org.apache.beam.sdk.transforms.DoFn; |
| import org.apache.beam.sdk.values.KV; |
| |
| /** |
| * Monitor that records the number of bytes flowing through a PCollection. |
| * |
| * <p>To use: apply a monitor in a desired place in the pipeline. This will capture how many bytes |
| * flew through this DoFn. Such information can be then collected and written out and queried using |
| * {@link org.apache.beam.sdk.testutils.metrics.MetricsReader}. |
| */ |
| public class ByteMonitor extends DoFn<KV<byte[], byte[]>, KV<byte[], byte[]>> { |
| |
| private Counter totalBytes; |
| |
| public ByteMonitor(String namespace, String name) { |
| this.totalBytes = Metrics.counter(namespace, name); |
| } |
| |
| @ProcessElement |
| public void processElement(ProcessContext c) { |
| totalBytes.inc(c.element().getKey().length + c.element().getValue().length); |
| c.output(c.element()); |
| } |
| } |