org.apache.unomi.extensions.log4j.SafeExtendedThrowablePatternConverter Maven / Gradle / Ivy
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/*
* 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.unomi.extensions.log4j;
import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.impl.ThrowableProxy;
import org.apache.logging.log4j.core.pattern.ConverterKeys;
import org.apache.logging.log4j.core.pattern.PatternConverter;
import org.apache.logging.log4j.core.pattern.ThrowablePatternConverter;
import org.apache.logging.log4j.util.Strings;
/**
* Outputs the Throwable portion of the LoggingEvent as a full stack trace
* unless this converter's option is 'short', where it just outputs the first line of the trace, or if
* the number of lines to print is explicitly specified.
*
* The extended stack trace will also include the location of where the class was loaded from and the
* version of the jar if available.
*
* If the message of the throwable contains a carriage return or line feed character, it gets encoded
* to prevent log injection.
*
* Originally written by Benjamin Papez (Jahia) [email protected]
* Contributed to Apache Unomi by Jahia Solutions Group SA
*/
@Plugin(
name = "SafeExtendedThrowablePatternConverter",
category = PatternConverter.CATEGORY,
elementType = "converter",
printObject = true
)
@ConverterKeys({ "sxEx", "sxThrowable", "sxException" })
public final class SafeExtendedThrowablePatternConverter extends ThrowablePatternConverter {
private static final String STACKTRACE_LINE_START = "\n\tat";
private static final String NESTED_STACKTRACE_LINE_START = "\n\t\tat";
/**
* Private constructor.
*
* @param config
* @param options options, may be null.
*/
private SafeExtendedThrowablePatternConverter(final Configuration config, final String[] options) {
super("SafeExtendedThrowable", "throwable", options, config);
}
/**
* Gets an instance of the class.
*
* @param config The current Configuration.
* @param options pattern options, may be null. If first element is "short",
* only the first line of the throwable will be formatted.
* @return instance of class.
*/
public static SafeExtendedThrowablePatternConverter newInstance(final Configuration config, final String[] options) {
return new SafeExtendedThrowablePatternConverter(config, options);
}
/**
* {@inheritDoc}
*/
@Override
public void format(final LogEvent event, final StringBuilder toAppendTo) {
final ThrowableProxy proxy = event.getThrownProxy();
final Throwable throwable = event.getThrown();
if ((throwable != null || proxy != null) && options.anyLines()) {
if (proxy == null) {
super.format(event, toAppendTo);
return;
}
final String suffix = getSuffix(event);
final String extStackTrace = proxy.getExtendedStackTraceAsString(options.getIgnorePackages(), options.getTextRenderer(), suffix);
final int len = toAppendTo.length();
if (len > 0 && !Character.isWhitespace(toAppendTo.charAt(len - 1))) {
toAppendTo.append(' ');
}
this.appendExtendedStackTrace(toAppendTo, extStackTrace);
}
}
private void appendExtendedStackTrace(final StringBuilder toAppendTo, final String extStackTrace) {
if (!options.allLines() || !Strings.LINE_SEPARATOR.equals(options.getSeparator())) {
toAppendTo.append(replaceLineSeparator(extStackTrace));
} else {
int firstMessageWithCRLFIndex = indexOfMessageWithCRLF(extStackTrace);
if (firstMessageWithCRLFIndex != -1) {
toAppendTo.append(replaceLineSeparatorInMessages(extStackTrace, firstMessageWithCRLFIndex));
} else {
toAppendTo.append(extStackTrace);
}
}
}
private String replaceLineSeparator(String extStackTrace) {
String[] array = extStackTrace.split(Strings.LINE_SEPARATOR);
return StringUtils.join(array, options.getSeparator(), 0, options.minLines(array.length));
}
private int indexOfMessageWithCRLF(String extStackTrace) {
int messageStartIndex = 0;
int stackTraceStartIndex;
do {
stackTraceStartIndex = getNextIndex(extStackTrace.indexOf(STACKTRACE_LINE_START, messageStartIndex),
extStackTrace.indexOf(NESTED_STACKTRACE_LINE_START, messageStartIndex));
if (stackTraceStartIndex != -1) {
stackTraceStartIndex--;
if (StringUtils.lastIndexOf(extStackTrace, '\r', stackTraceStartIndex) >= messageStartIndex
|| StringUtils.lastIndexOf(extStackTrace, '\n', stackTraceStartIndex) >= messageStartIndex) {
return messageStartIndex;
} else if (stackTraceStartIndex != -1) {
messageStartIndex = getNextNestedMessageIndex(extStackTrace, stackTraceStartIndex);
}
}
} while (messageStartIndex != -1 && stackTraceStartIndex != -1);
return -1;
}
private int getNextNestedMessageIndex(String extStackTrace, int stackTraceStartIndex) {
return getNextIndex(extStackTrace.indexOf("Caused by:", stackTraceStartIndex),
extStackTrace.indexOf("Suppressed:", stackTraceStartIndex));
}
private int getNextNestedMessageIndex(StringBuilder extStackTrace, int stackTraceStartIndex) {
return getNextIndex(extStackTrace.indexOf("Caused by:", stackTraceStartIndex),
extStackTrace.indexOf("Suppressed:", stackTraceStartIndex));
}
private int getNextIndex(int firstIndex, int secondIndex) {
if (secondIndex == -1) {
return firstIndex;
} else if (firstIndex == -1) {
return secondIndex;
} else {
return Math.min(firstIndex, secondIndex);
}
}
private String replaceLineSeparatorInMessages(String extStackTrace, int messageWithCRLFIndex) {
final StringBuilder sb = new StringBuilder(extStackTrace);
do {
int beginningOfStackTrace = getNextIndex(sb.indexOf(STACKTRACE_LINE_START, messageWithCRLFIndex),
sb.indexOf(NESTED_STACKTRACE_LINE_START, messageWithCRLFIndex));
replaceCRLF(sb, messageWithCRLFIndex, beginningOfStackTrace);
messageWithCRLFIndex = indexOfNestedExceptionMessageWithCRLF(sb, beginningOfStackTrace);
} while (messageWithCRLFIndex != -1);
return sb.toString();
}
private int indexOfNestedExceptionMessageWithCRLF(StringBuilder extStackTrace, int startIndex) {
int stackTraceStartIndex;
do {
startIndex = getNextNestedMessageIndex(extStackTrace, startIndex);
if (startIndex == -1) {
return startIndex;
}
stackTraceStartIndex = getNextIndex(extStackTrace.indexOf(STACKTRACE_LINE_START, startIndex),
extStackTrace.indexOf(NESTED_STACKTRACE_LINE_START, startIndex));
if (stackTraceStartIndex != -1) {
stackTraceStartIndex--;
if (StringUtils.lastIndexOf(extStackTrace, '\r', stackTraceStartIndex) >= startIndex
|| StringUtils.lastIndexOf(extStackTrace, '\n', stackTraceStartIndex) >= startIndex) {
return startIndex;
}
}
startIndex = stackTraceStartIndex;
} while (startIndex != -1 && stackTraceStartIndex != -1);
return -1;
}
private void replaceCRLF(StringBuilder toAppendTo, int start, int end) {
for (int i = end - 1; i >= start; i--) {
final char c = toAppendTo.charAt(i);
switch (c) {
case '\r':
toAppendTo.setCharAt(i, '\\');
toAppendTo.insert(i + 1, 'r');
break;
case '\n':
toAppendTo.setCharAt(i, '\\');
toAppendTo.insert(i + 1, 'n');
break;
default:
break;
}
}
}
}