我尝试使用Log4j2配置JsonLayaout。我想在JSON中只有一条消息中的堆栈跟踪。我知道我必须使用属性＆＃34;完成＆＃34;。
我创建的示例类是：
public class MyApp {
private static final Logger logger = LogManager.getLogger(MyApp.class);
public static void main(final String... args) {
logger.debug("Entering application.");
try{
int i = 0;
int a = 5 / i;
}catch(Exception e){
//StringWriter sw = new StringWriter();
//e.printStackTrace(new PrintWriter(sw));
//String exceptionAsString = sw.toString();
logger.error(exceptionAsString);
}
}
}
log4j2.properties是：
name=PropertiesConfig
property.filename = logs
appenders = file, console
appender.console.type = Console
appender.console.name = STDOUT
appender.console.layout.type = JSONLayout
appender.console.layout.complete="false"
#appender.console.layout.compact = true
#appender.console.layout.pattern = [%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
appender.file.type = File
appender.file.name = LOGFILE
appender.file.fileName=/var/tmp/propertieslogs.log
appender.file.layout.type=JSONLayout
appender.file.layout.complete="true"
#appender.file.layout.pattern=[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
rootLogger.level = debug
rootLogger.appenderRefs = stdout, logfile
rootLogger.appenderRef.stdout.ref = STDOUT
rootLogger.appenderRef.logfile.ref = LOGFILE
输出我喜欢它：
[
{
"logger":"com.foo.Bar",
"timestamp":"1376681196470",
"level":"INFO",
"threadId":1,
"thread":"main",
"threadPriority":1,
"message":"Message flushed with immediate flush=true"
},
{
"logger":"com.foo.Bar",
"timestamp":"1376681196471",
"level":"ERROR",
"threadId":1,
"thread":"main",
"threadPriority":1,
"message":"Message flushed with immediate flush=true",
"throwable":"java.lang.IllegalArgumentException: badarg\\n\\tat org.apache.logging.log4j.core.appender.JSONCompleteFileAppenderTest.testFlushAtEndOfBatch(JSONCompleteFileAppenderTest.java:54)\\n\\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\\n\\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)\\n\\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\\n\\tat java.lang.reflect.Method.invoke(Method.java:606)\\n\\tat org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)\\n\\tat org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)\\n\\tat org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)\\n\\tat org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)\\n\\tat org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)\\n\\tat org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)\\n\\tat org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)\\n\\tat org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)\\n\\tat org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)\\n\\tat org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)\\n\\tat org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)\\n\\tat org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)\\n\\tat org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)\\n\\tat org.junit.runners.ParentRunner.run(ParentRunner.java:309)\\n\\tat org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)\\n\\tat org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)\\n\\tat org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)\\n\\tat org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)\\n\\tat org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)\\n\\tat org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)\\n"
}
]
但我明白了：
{
"timeMillis" : 1474362834903,
"thread" : "main",
"level" : "ERROR",
"loggerName" : "test.MyApp",
"message" : "Exception:",
"thrown" : {
"commonElementCount" : 0,
"localizedMessage" : "/ by zero",
"message" : "/ by zero",
"name" : "java.lang.ArithmeticException",
"extendedStackTrace" : [ {
"class" : "test.MyApp",
"method" : "main",
"file" : "MyApp.java",
"line" : 24,
"exact" : true,
"location" : "classes/",
"version" : "?"
}, {
"class" : "sun.reflect.NativeMethodAccessorImpl",
"method" : "invoke0",
"file" : "NativeMethodAccessorImpl.java",
"line" : -2,
"exact" : false,
"location" : "?",
"version" : "1.8.0_91"
}, {
"class" : "sun.reflect.NativeMethodAccessorImpl",
"method" : "invoke",
"file" : "NativeMethodAccessorImpl.java",
"line" : 62,
"exact" : false,
"location" : "?",
"version" : "1.8.0_91"
}, {
"class" : "sun.reflect.DelegatingMethodAccessorImpl",
"method" : "invoke",
"file" : "DelegatingMethodAccessorImpl.java",
"line" : 43,
"exact" : false,
"location" : "?",
"version" : "1.8.0_91"
}, {
"class" : "java.lang.reflect.Method",
"method" : "invoke",
"file" : "Method.java",
"line" : 498,
"exact" : false,
"location" : "?",
"version" : "1.8.0_91"
}, {
"class" : "com.intellij.rt.execution.application.AppMain",
"method" : "main",
"file" : "AppMain.java",
"line" : 147,
"exact" : true,
"location" : "idea_rt.jar",
"version" : "?"
} ]
},
"endOfBatch" : false,
"loggerFqcn" : "org.apache.logging.log4j.spi.AbstractLogger",
"threadId" : 1,
"threadPriority" : 5
}
我应该像在代码中一样为消息构建一个String，或者如何在日志中使用所有堆栈跟踪来完成throwable属性？
如果我使用此代码：
public static void main(final String... args) {
// Set up a simple configuration that logs on the console.
logger.debug("Entering application.");
try{
int i = 0;
int a = 5 / i;
}catch(Exception e){
StringWriter sw = new StringWriter();
e.printStackTrace(new PrintWriter(sw));
String exceptionAsString = sw.toString();
logger.error(exceptionAsString);
}
}
}
我几乎得到了我想要的东西：
{
"timeMillis" : 1474542115319,
"thread" : "main",
"level" : "DEBUG",
"loggerName" : "MyApp",
"message" : "Entering application.",
"endOfBatch" : false,
"loggerFqcn" : "org.apache.logging.log4j.spi.AbstractLogger",
"contextMap" : [ ]
}{
"timeMillis" : 1474542115573,
"thread" : "main",
"level" : "ERROR",
"loggerName" : "MyApp",
"message" : "java.lang.ArithmeticException: / by zero\n\tat MyApp.main(MyApp.java:23)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)\n",
"endOfBatch" : false,
"loggerFqcn" : "org.apache.logging.log4j.spi.AbstractLogger",
"contextMap" : [ ]
}
但是，我想我可以自动完成，而无需将stacktrace解析为String。
答案 0 :(得分：2)
我使用自定义Log4j布局解决了这个问题：
@Plugin(name = "FlatJsonLayout", category = "Core", elementType = "layout", printObject = true)
public class FlatJsonLayout extends AbstractStringLayout {
private final ObjectMapper objectMapper;
FlatJsonLayout(Charset charset) {
super(charset);
SimpleModule module = new SimpleModule();
module.addSerializer(LogEvent.class, new LogEventSerializer());
module.addSerializer(Throwable.class, new ThrowableSerializer());
module.addSerializer(ReadOnlyStringMap.class, new ContextDataSerializer() {
});
objectMapper = new ObjectMapper();
objectMapper.registerModule(module);
objectMapper.setSerializationInclusion(JsonInclude.Include.NON_EMPTY);
}
@Override
public String toSerializable(LogEvent logEvent) {
try {
return objectMapper.writeValueAsString(logEvent);
} catch (JsonProcessingException e) {
throw new IllegalStateException(e);
}
}
private static class LogEventSerializer extends StdSerializer<LogEvent> {
LogEventSerializer() {
super(LogEvent.class);
}
@Override
public void serialize(LogEvent value, JsonGenerator gen, SerializerProvider provider) throws IOException {
gen.writeStartObject();
gen.writeNumberField("timeMillis", value.getTimeMillis());
gen.writeStringField("threadName", value.getThreadName());
gen.writeStringField("level", value.getLevel().name());
gen.writeStringField("loggerName", value.getLoggerName());
gen.writeObjectField("marker", value.getMarker());
gen.writeObjectField("message", value.getMessage().getFormattedMessage());
gen.writeObjectField("thrown", value.getThrown());
gen.writeObjectField("ContextMap", value.getContextData());
gen.writeObjectField("ContextStack", value.getContextStack());
gen.writeStringField("loggerFQCN", value.getLoggerFqcn());
gen.writeObjectField("Source", value.getSource());
gen.writeBooleanField("endOfBatch", value.isEndOfBatch());
gen.writeEndObject();
}
}
private static class ThrowableSerializer extends StdSerializer<Throwable> {
ThrowableSerializer() {
super(Throwable.class);
}
@Override
public void serialize(Throwable value, JsonGenerator gen, SerializerProvider provider) throws IOException {
try (StringWriter stringWriter = new StringWriter()) {
try (PrintWriter printWriter = new PrintWriter(stringWriter)) {
value.printStackTrace(printWriter);
gen.writeString(stringWriter.toString());
}
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
}
@PluginBuilderFactory
public static <B extends Builder<B>> B newBuilder() {
return new Builder<B>().asBuilder();
}
public static class Builder<B extends Builder<B>> extends org.apache.logging.log4j.core.layout.AbstractStringLayout.Builder<B> implements org.apache.logging.log4j.core.util.Builder<FlatJsonLayout> {
Builder() {
this.setCharset(StandardCharsets.UTF_8);
}
public FlatJsonLayout build() {
return new FlatJsonLayout(this.getCharset());
}
}
}
该类必须位于应用程序的类路径中。然后可以像log4j2.xml这样配置它：
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="info">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<FlatJsonLayout/>
</Console>
</Appenders>
<Loggers>
<Root level="info">
<AppenderRef ref="Console"/>
</Root>
</Loggers>
</Configuration>
答案 1 :(得分：1)
设置compact="true"和eventEol="true"适合我
<JsonLayout complete="false" compact="true" eventEol="true">
答案 2 :(得分：1)
<JsonLayout compact="true" eventEol="true" stacktraceAsString="true" >
这会有所帮助。
答案 3 :(得分：0)
在属性文件appender.console.layout.complete上是布尔型而不是字符串，因此请更改：
appender.console.layout.complete="false"
收件人：
appender.console.layout.complete = false
答案 4 :(得分：0)
今天使用 - log4j 2.9.0 或更高版本在设置 stacktraceAsString="true" 时会将 stacktrace 打印为单行