| /* |
| * 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.runners.dataflow.worker.logging; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.io.OutputStream; |
| import java.io.PrintStream; |
| import java.io.UnsupportedEncodingException; |
| import java.nio.charset.StandardCharsets; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| import java.util.logging.Handler; |
| import java.util.logging.Level; |
| import java.util.logging.LogRecord; |
| import java.util.logging.Logger; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.annotations.VisibleForTesting; |
| |
| /** |
| * A {@link PrintStream} factory that creates {@link PrintStream}s which output to the specified JUL |
| * {@link Handler} at the specified {@link Level}. |
| */ |
| class JulHandlerPrintStreamAdapterFactory { |
| private static final AtomicBoolean outputWarning = new AtomicBoolean(false); |
| |
| /** |
| * Creates a {@link PrintStream} which redirects all output to the JUL {@link Handler} with the |
| * specified {@code loggerName} and {@code level}. |
| */ |
| static PrintStream create(Handler handler, String loggerName, Level messageLevel) { |
| try { |
| return new PrintStream( |
| new JulHandlerAdapterOutputStream(handler, loggerName, messageLevel), |
| false, |
| StandardCharsets.UTF_8.name()); |
| } catch (UnsupportedEncodingException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| |
| /** |
| * An output stream adapter which is able to take a stream of UTF-8 data and output to a named JUL |
| * log handler. The log messages will be buffered until the system dependent new line separator is |
| * seen, at which point the buffered string will be output. |
| */ |
| private static class JulHandlerAdapterOutputStream extends OutputStream { |
| private static final String LOGGING_DISCLAIMER = |
| String.format( |
| "Please use a logger instead of System.out or System.err.%n" |
| + "Please switch to using org.slf4j.Logger.%n" |
| + "See: https://cloud.google.com/dataflow/pipelines/logging"); |
| // This limits the number of bytes which we buffer in case we don't see a newline character. |
| private static final int BUFFER_LIMIT = 1 << 14; // 16384 bytes |
| private static final byte[] NEW_LINE = System.lineSeparator().getBytes(StandardCharsets.UTF_8); |
| |
| /** Hold reference of named logger to check configured {@link Level}. */ |
| private Logger logger; |
| |
| private Handler handler; |
| private String loggerName; |
| private ByteArrayOutputStream baos; |
| private Level messageLevel; |
| private int matched = 0; |
| |
| private JulHandlerAdapterOutputStream(Handler handler, String loggerName, Level logLevel) { |
| this.handler = handler; |
| this.loggerName = loggerName; |
| this.messageLevel = logLevel; |
| this.logger = Logger.getLogger(loggerName); |
| this.baos = new ByteArrayOutputStream(BUFFER_LIMIT); |
| } |
| |
| @Override |
| public void write(int b) { |
| if (outputWarning.compareAndSet(false, true)) { |
| publish(Level.WARNING, LOGGING_DISCLAIMER); |
| } |
| |
| baos.write(b); |
| // Check to see if the next byte matches further into new line string. |
| if (NEW_LINE[matched] == b) { |
| matched += 1; |
| // If we have matched the entire new line, output the contents of the buffer. |
| if (matched == NEW_LINE.length) { |
| output(); |
| } |
| } else { |
| // Reset the match |
| matched = 0; |
| } |
| if (baos.size() == BUFFER_LIMIT) { |
| output(); |
| } |
| } |
| |
| @Override |
| public void flush() throws IOException { |
| output(); |
| } |
| |
| @Override |
| public void close() throws IOException { |
| output(); |
| } |
| |
| private void output() { |
| // If nothing was output, do not log anything |
| if (baos.size() == 0) { |
| return; |
| } |
| try { |
| String message = baos.toString(StandardCharsets.UTF_8.name()); |
| // Strip the new line if it exists |
| if (message.endsWith(System.lineSeparator())) { |
| message = message.substring(0, message.length() - System.lineSeparator().length()); |
| } |
| |
| publish(messageLevel, message); |
| } catch (UnsupportedEncodingException e) { |
| publish( |
| Level.SEVERE, String.format("Unable to decode string output to stdout/stderr %s", e)); |
| } |
| matched = 0; |
| baos.reset(); |
| } |
| |
| private void publish(Level level, String message) { |
| if (logger.isLoggable(level)) { |
| LogRecord log = new LogRecord(level, message); |
| log.setLoggerName(loggerName); |
| handler.publish(log); |
| } |
| } |
| } |
| |
| @VisibleForTesting |
| static void reset() { |
| outputWarning.set(false); |
| } |
| } |