版本
2.2.x
日志系统初始化流程
- 应用启动时，ApplicationStartingEvent触发，屏蔽所有日志
- ApplicationEnvironmentPreparedEvent触发，清空所有日志配置，重新初始化日志系统
- 配置变更，EnvironmentChangeEvent触发，重新设置日志级别
源码
- org.springframework.cloud.bootstrap.LoggingSystemShutdownListener
public class LoggingSystemShutdownListener
implements ApplicationListener<ApplicationEnvironmentPreparedEvent>, Ordered {
@Override
public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
shutdownLogging();
}
private void shutdownLogging() {
LoggingSystem loggingSystem = LoggingSystem
.get(ClassUtils.getDefaultClassLoader());
loggingSystem.cleanUp();
loggingSystem.beforeInitialize();
}
}
- org.springframework.boot.context.logging.LoggingApplicationListener
// 应用启动时
private void onApplicationStartingEvent(ApplicationStartingEvent event) {
// 获取日志系统实例
this.loggingSystem = LoggingSystem.get(event.getSpringApplication().getClassLoader());
// 关闭所有日志
this.loggingSystem.beforeInitialize();
}
// 应用环境准备完成时
private void onApplicationEnvironmentPreparedEvent(ApplicationEnvironmentPreparedEvent event) {
if (this.loggingSystem == null) {
this.loggingSystem = LoggingSystem.get(event.getSpringApplication().getClassLoader());
}
// 初始化日志系统
initialize(event.getEnvironment(), event.getSpringApplication().getClassLoader());
}
protected void initialize(ConfigurableEnvironment environment, ClassLoader classLoader) {
new LoggingSystemProperties(environment).apply();
this.logFile = LogFile.get(environment);
if (this.logFile != null) {
this.logFile.applyToSystemProperties();
}
this.loggerGroups = new LoggerGroups(DEFAULT_GROUP_LOGGERS);
initializeEarlyLoggingLevel(environment);
// 初始化日志系统
initializeSystem(environment, this.loggingSystem, this.logFile);
initializeFinalLoggingLevels(environment, this.loggingSystem);
registerShutdownHookIfNecessary(environment, this.loggingSystem);
}
- org.springframework.boot.logging.LoggingSystem
根据系统属性org.springframework.boot.logging.LoggingSystem的值判断选用何种日志系统
private static final Map<String, String> SYSTEMS;
static {
Map<String, String> systems = new LinkedHashMap<>();
systems.put("ch.qos.logback.core.Appender", "org.springframework.boot.logging.logback.LogbackLoggingSystem");
systems.put("org.apache.logging.log4j.core.impl.Log4jContextFactory",
"org.springframework.boot.logging.log4j2.Log4J2LoggingSystem");
systems.put("java.util.logging.LogManager", "org.springframework.boot.logging.java.JavaLoggingSystem");
SYSTEMS = Collections.unmodifiableMap(systems);
}
public static LoggingSystem get(ClassLoader classLoader) {
// 获取日志系统类型
String loggingSystem = System.getProperty(SYSTEM_PROPERTY);
if (StringUtils.hasLength(loggingSystem)) {
if (NONE.equals(loggingSystem)) {
return new NoOpLoggingSystem();
}
return get(classLoader, loggingSystem);
}
// 获取存在的日志系统类
return SYSTEMS.entrySet().stream().filter((entry) -> ClassUtils.isPresent(entry.getKey(), classLoader))
.map((entry) -> get(classLoader, entry.getValue())).findFirst()
.orElseThrow(() -> new IllegalStateException("No suitable logging system located"));
}
// 创建日志系统实例
private static LoggingSystem get(ClassLoader classLoader, String loggingSystemClass) {
try {
Class<?> systemClass = ClassUtils.forName(loggingSystemClass, classLoader);
Constructor<?> constructor = systemClass.getDeclaredConstructor(ClassLoader.class);
constructor.setAccessible(true);
return (LoggingSystem) constructor.newInstance(classLoader);
}
catch (Exception ex) {
throw new IllegalStateException(ex);
}
}
- org.springframework.boot.logging.AbstractLoggingSystem
@Override
public void initialize(LoggingInitializationContext initializationContext, String configLocation, LogFile logFile) {
if (StringUtils.hasLength(configLocation)) {
initializeWithSpecificConfig(initializationContext, configLocation, logFile);
return;
}
// 没有指定配置文件
initializeWithConventions(initializationContext, logFile);
}
private void initializeWithConventions(LoggingInitializationContext initializationContext, LogFile logFile) {
// 获取自定义配置文件
String config = getSelfInitializationConfig();
if (config != null && logFile == null) {
// self initialization has occurred, reinitialize in case of property changes
reinitialize(initializationContext);
return;
}
// 获取spring配置
if (config == null) {
config = getSpringInitializationConfig();
}
if (config != null) {
loadConfiguration(initializationContext, config, logFile);
return;
}
// 不存在配置，加载默认配置
loadDefaults(initializationContext, logFile);
}
- org.springframework.boot.logging.logback.LogbackLoggingSystem
public void beforeInitialize() {
LoggerContext loggerContext = getLoggerContext();
if (isAlreadyInitialized(loggerContext)) {
return;
}
super.beforeInitialize();
// 屏蔽所有日志
loggerContext.getTurboFilterList().add(FILTER);
}
@Override
protected void loadDefaults(LoggingInitializationContext initializationContext, LogFile logFile) {
LoggerContext context = getLoggerContext();
// 此处重置上下文中原有配置
stopAndReset(context);
boolean debug = Boolean.getBoolean("logback.debug");
if (debug) {
StatusListenerConfigHelper.addOnConsoleListenerInstance(context, new OnConsoleStatusListener());
}
LogbackConfigurator configurator = debug ? new DebugLogbackConfigurator(context)
: new LogbackConfigurator(context);
Environment environment = initializationContext.getEnvironment();
context.putProperty(LoggingSystemProperties.LOG_LEVEL_PATTERN,
environment.resolvePlaceholders("${logging.pattern.level:${LOG_LEVEL_PATTERN:%5p}}"));
context.putProperty(LoggingSystemProperties.LOG_DATEFORMAT_PATTERN, environment.resolvePlaceholders(
"${logging.pattern.dateformat:${LOG_DATEFORMAT_PATTERN:yyyy-MM-dd HH:mm:ss.SSS}}"));
context.putProperty(LoggingSystemProperties.ROLLING_FILE_NAME_PATTERN, environment
.resolvePlaceholders("${logging.pattern.rolling-file-name:${LOG_FILE}.%d{yyyy-MM-dd}.%i.gz}"));
new DefaultLogbackConfiguration(initializationContext, logFile).apply(configurator);
context.setPackagingDataEnabled(true);
}
- org.springframework.boot.logging.logback.DefaultLogbackConfiguration
/**
* Default logback configuration used by Spring Boot. Uses {@link LogbackConfigurator} to
* improve startup time. See also the {@code defaults.xml}, {@code console-appender.xml}
* and {@code file-appender.xml} files provided for classic {@code logback.xml} use.
*
* @author Phillip Webb
* @author Madhura Bhave
* @author Vedran Pavic
* @author Robert Thornton
*/
class DefaultLogbackConfiguration {
private static final String CONSOLE_LOG_PATTERN = "%clr(%d{${LOG_DATEFORMAT_PATTERN:-yyyy-MM-dd HH:mm:ss.SSS}}){faint} "
+ "%clr(${LOG_LEVEL_PATTERN:-%5p}) %clr(${PID:- }){magenta} %clr(---){faint} "
+ "%clr([%15.15t]){faint} %clr(%-40.40logger{39}){cyan} "
+ "%clr(:){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}";
private static final String FILE_LOG_PATTERN = "%d{${LOG_DATEFORMAT_PATTERN:-yyyy-MM-dd HH:mm:ss.SSS}} "
+ "${LOG_LEVEL_PATTERN:-%5p} ${PID:- } --- [%t] %-40.40logger{39} : %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}";
private static final DataSize MAX_FILE_SIZE = DataSize.ofMegabytes(10);
private static final Integer MAX_FILE_HISTORY = 7;
private final PropertyResolver patterns;
private final LogFile logFile;
DefaultLogbackConfiguration(LoggingInitializationContext initializationContext, LogFile logFile) {
this.patterns = getPatternsResolver(initializationContext.getEnvironment());
this.logFile = logFile;
}
private PropertyResolver getPatternsResolver(Environment environment) {
if (environment == null) {
return new PropertySourcesPropertyResolver(null);
}
if (environment instanceof ConfigurableEnvironment) {
PropertySourcesPropertyResolver resolver = new PropertySourcesPropertyResolver(
((ConfigurableEnvironment) environment).getPropertySources());
resolver.setIgnoreUnresolvableNestedPlaceholders(true);
return resolver;
}
return environment;
}
void apply(LogbackConfigurator config) {
synchronized (config.getConfigurationLock()) {
base(config);
Appender<ILoggingEvent> consoleAppender = consoleAppender(config);
if (this.logFile != null) {
Appender<ILoggingEvent> fileAppender = fileAppender(config, this.logFile.toString());
config.root(Level.INFO, consoleAppender, fileAppender);
}
else {
config.root(Level.INFO, consoleAppender);
}
}
}
private void base(LogbackConfigurator config) {
config.conversionRule("clr", ColorConverter.class);
config.conversionRule("wex", WhitespaceThrowableProxyConverter.class);
config.conversionRule("wEx", ExtendedWhitespaceThrowableProxyConverter.class);
config.logger("org.apache.catalina.startup.DigesterFactory", Level.ERROR);
config.logger("org.apache.catalina.util.LifecycleBase", Level.ERROR);
config.logger("org.apache.coyote.http11.Http11NioProtocol", Level.WARN);
config.logger("org.apache.sshd.common.util.SecurityUtils", Level.WARN);
config.logger("org.apache.tomcat.util.net.NioSelectorPool", Level.WARN);
config.logger("org.eclipse.jetty.util.component.AbstractLifeCycle", Level.ERROR);
config.logger("org.hibernate.validator.internal.util.Version", Level.WARN);
}
private Appender<ILoggingEvent> consoleAppender(LogbackConfigurator config) {
ConsoleAppender<ILoggingEvent> appender = new ConsoleAppender<>();
PatternLayoutEncoder encoder = new PatternLayoutEncoder();
String logPattern = this.patterns.getProperty("logging.pattern.console", CONSOLE_LOG_PATTERN);
encoder.setPattern(OptionHelper.substVars(logPattern, config.getContext()));
config.start(encoder);
appender.setEncoder(encoder);
config.appender("CONSOLE", appender);
return appender;
}
private Appender<ILoggingEvent> fileAppender(LogbackConfigurator config, String logFile) {
RollingFileAppender<ILoggingEvent> appender = new RollingFileAppender<>();
PatternLayoutEncoder encoder = new PatternLayoutEncoder();
String logPattern = this.patterns.getProperty("logging.pattern.file", FILE_LOG_PATTERN);
encoder.setPattern(OptionHelper.substVars(logPattern, config.getContext()));
appender.setEncoder(encoder);
config.start(encoder);
appender.setFile(logFile);
setRollingPolicy(appender, config, logFile);
config.appender("FILE", appender);
return appender;
}
private void setRollingPolicy(RollingFileAppender<ILoggingEvent> appender, LogbackConfigurator config,
String logFile) {
SizeAndTimeBasedRollingPolicy<ILoggingEvent> rollingPolicy = new SizeAndTimeBasedRollingPolicy<>();
rollingPolicy.setCleanHistoryOnStart(
this.patterns.getProperty("logging.file.clean-history-on-start", Boolean.class, false));
rollingPolicy.setFileNamePattern(
this.patterns.getProperty("logging.pattern.rolling-file-name", logFile + ".%d{yyyy-MM-dd}.%i.gz"));
setMaxFileSize(rollingPolicy, getDataSize("logging.file.max-size", MAX_FILE_SIZE));
rollingPolicy
.setMaxHistory(this.patterns.getProperty("logging.file.max-history", Integer.class, MAX_FILE_HISTORY));
DataSize totalSizeCap = getDataSize("logging.file.total-size-cap",
DataSize.ofBytes(CoreConstants.UNBOUNDED_TOTAL_SIZE_CAP));
rollingPolicy.setTotalSizeCap(new FileSize(totalSizeCap.toBytes()));
appender.setRollingPolicy(rollingPolicy);
rollingPolicy.setParent(appender);
config.start(rollingPolicy);
}
private void setMaxFileSize(SizeAndTimeBasedRollingPolicy<ILoggingEvent> rollingPolicy, DataSize maxFileSize) {
try {
rollingPolicy.setMaxFileSize(new FileSize(maxFileSize.toBytes()));
}
catch (NoSuchMethodError ex) {
// Logback < 1.1.8 used String configuration
Method method = ReflectionUtils.findMethod(SizeAndTimeBasedRollingPolicy.class, "setMaxFileSize",
String.class);
ReflectionUtils.invokeMethod(method, rollingPolicy, String.valueOf(maxFileSize.toBytes()));
}
}
private DataSize getDataSize(String property, DataSize defaultSize) {
String value = this.patterns.getProperty(property);
if (value == null) {
return defaultSize;
}
try {
return DataSize.parse(value);
}
catch (IllegalArgumentException ex) {
FileSize fileSize = FileSize.valueOf(value);
return DataSize.ofBytes(fileSize.getSize());
}
}
}