    001    /*
    002     * Licensed to the Apache Software Foundation (ASF) under one or more
    003     * contributor license agreements. See the NOTICE file distributed with
    004     * this work for additional information regarding copyright ownership.
    005     * The ASF licenses this file to You under the Apache license, Version 2.0
    006     * (the "License"); you may not use this file except in compliance with
    007     * the License. You may obtain a copy of the License at
    008     *
    009     *      http://www.apache.org/licenses/LICENSE-2.0
    010     *
    011     * Unless required by applicable law or agreed to in writing, software
    012     * distributed under the License is distributed on an "AS IS" BASIS,
    013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014     * See the license for the specific language governing permissions and
    015     * limitations under the license.
    016     */
    017    package org.apache.logging.log4j.core.net.server;
    018
    019    import java.io.IOException;
    020    import java.io.InputStream;
    021    import java.nio.charset.Charset;
    022
    023    import org.apache.logging.log4j.core.LogEvent;
    024    import org.apache.logging.log4j.core.LogEventListener;
    025    import org.apache.logging.log4j.core.impl.Log4jLogEvent;
    026    import org.apache.logging.log4j.util.Strings;
    027
    028    import com.fasterxml.jackson.databind.ObjectMapper;
    029    import com.fasterxml.jackson.databind.ObjectReader;
    030
    031    /**
    032     * Reads and logs {@link LogEvent}s from an {@link InputStream}.
    033     */
    034    public abstract class InputStreamLogEventBridge extends AbstractLogEventBridge<InputStream> {
    035
    036        private final int bufferSize;
    037
    038        private final Charset charset;
    039
    040        private final String eventEndMarker;
    041
    042        private final ObjectReader objectReader;
    043
    044        public InputStreamLogEventBridge(final ObjectMapper mapper, final int bufferSize, final Charset charset, final String eventEndMarker) {
    045            this.bufferSize = bufferSize;
    046            this.charset = charset;
    047            this.eventEndMarker = eventEndMarker;
    048            this.objectReader = mapper.reader(Log4jLogEvent.class);
    049        }
    050
    051        abstract protected int[] getEventIndices(final String text, int beginIndex);
    052
    053        @Override
    054        public void logEvents(final InputStream inputStream, final LogEventListener logEventListener) throws IOException {
    055            String workingText = Strings.EMPTY;
    056            try {
    057                // Allocate buffer once
    058                final byte[] buffer = new byte[bufferSize];
    059                String textRemains = workingText = Strings.EMPTY;
    060                while (true) {
    061                    // Process until the stream is EOF.
    062                    final int streamReadLength = inputStream.read(buffer);
    063                    if (streamReadLength == END) {
    064                        // The input stream is EOF
    065                        break;
    066                    }
    067                    final String text = workingText = textRemains + new String(buffer, 0, streamReadLength, charset);
    068                    int beginIndex = 0;
    069                    while (true) {
    070                        // Extract and log all XML events in the buffer
    071                        final int[] pair = getEventIndices(text, beginIndex);
    072                        final int eventStartMarkerIndex = pair[0];
    073                        if (eventStartMarkerIndex < 0) {
    074                            // No more events or partial XML only in the buffer.
    075                            // Save the unprocessed string part
    076                            textRemains = text.substring(beginIndex);
    077                            break;
    078                        }
    079                        final int eventEndMarkerIndex = pair[1];
    080                        if (eventEndMarkerIndex > 0) {
    081                            final int eventEndXmlIndex = eventEndMarkerIndex + eventEndMarker.length();
    082                            final String textEvent = workingText = text.substring(eventStartMarkerIndex, eventEndXmlIndex);
    083                            final LogEvent logEvent = unmarshal(textEvent);
    084                            logEventListener.log(logEvent);
    085                            beginIndex = eventEndXmlIndex;
    086                        } else {
    087                            // No more events or partial XML only in the buffer.
    088                            // Save the unprocessed string part
    089                            textRemains = text.substring(beginIndex);
    090                            break;
    091                        }
    092                    }
    093                }
    094            } catch (final IOException ex) {
    095                logger.error(workingText, ex);
    096            }
    097        }
    098
    099        protected Log4jLogEvent unmarshal(final String jsonEvent) throws IOException {
    100            return this.objectReader.readValue(jsonEvent);
    101        }
    102
    103    }