在代码中添加了Spring Boot Remove Logback Appender自动配置

问题描述

我想进行Spring自动配置，以添加LogstashTcpsocketAppender。

我所做的：

1. LogstashTcpsocketAppender已从LogstashAutoConfiguration.java添加到LoggerContext中。

@Configuration
@ConditionalOnProperty(name = "logging.logstash.url")
@requiredArgsConstructor
public class LogstashAutoConfiguration {
    
    @Value("${spring.application.name:null}")
    private String applicationName;
    
    @Value("${logging.logstash.url}")
    private String logstashUrl;
    
    @Bean
    public LogstashTcpsocketAppender logstashAppender() {
        LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();

        LogstashTcpsocketAppender logstashTcpsocketAppender = new LogstashTcpsocketAppender();
        logstashTcpsocketAppender.setName("LOGSTASH");
        logstashTcpsocketAppender.setContext(loggerContext);
        logstashTcpsocketAppender.addDestination(logstashUrl);

        LogstashEncoder encoder = new LogstashEncoder();
        encoder.setIncludeMdc(true);
        encoder.getFieldNames().setLevelValue(null);
        encoder.setCustomFields(String.format("{\"app_name\":\"%s\"}",applicationName));

        logstashTcpsocketAppender.setEncoder(encoder);
        logstashTcpsocketAppender.start();

        loggerContext.getLogger(Logger.ROOT_LOGGER_NAME).addAppender(logstashTcpsocketAppender);

        return logstashTcpsocketAppender;
    }
}

1. 过一会儿，Spring Boot触发一个事件将重新配置应用程序。 （例如，我使用Consul，所以我只更改键/值存储中的属性，然后春季刷新我的上下文）
2. 它在AbstractLoggingSystem.java中调用InitializeWithConventions
3. 然后它将在LogbackLoggingSystem.java中调用loadConfiguration
4. 然后它将停止stopAndReset（loggerContext）。在这里它将停止所有附加程序，并会重置resetAllListeners（）;,这将清除所有的Logback侦听器。 （所以我不能再将Logback侦听器用于添加附加程序）

是否有通过Spring自动配置添加Appender的正确方法？ 春天使应用程序重新配置时，如何防止从LoggerContext中删除LogstashTcpsocketAppender？

解决方法

在上述Configuration类中，目的是为appender添加一个Logstash，并负责发送日志。

如果环境变量发生更改或上下文得到刷新，则可以侦听相关事件，然后检查是否已配置Logstash附加程序。确保仅在缺少Logstash附加程序时添加它。

这里是可以做的事情。

@Configuration
@ConditionalOnProperty(name = "logging.logstash.url")
public class LogstashAppenderConfiguration {

    @Value("${spring.application.name:null}")
    private String applicationName;

    @Value("${logging.logstash.url}")
    private String logstashUrl;

    @EventListener(ContextRefreshedEvent.class)
    public void onContextRefreshedEvent(ContextRefreshedEvent event) {
        this.addLogStashAppenderIfMissing();
    }

    @EventListener(RefreshScopeRefreshedEvent.class)
    public void onRefreshScopeRefreshedEvent(RefreshScopeRefreshedEvent event) {
        this.addLogStashAppenderIfMissing();
    }

    @EventListener(EnvironmentChangeEvent.class)
    public void onEnvironmentChangeEvent(EnvironmentChangeEvent event) {
        this.addLogStashAppenderIfMissing();
    }

    public void addLogStashAppenderIfMissing() {
        LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
        synchronized (this) {
            if (Objects.isNull(loggerContext.getLogger(Logger.ROOT_LOGGER_NAME).getAppender("LOGSTASH"))) {
                LogstashTcpSocketAppender logstashTcpSocketAppender = new LogstashTcpSocketAppender();
                logstashTcpSocketAppender.setName("LOGSTASH");
                logstashTcpSocketAppender.setContext(loggerContext);
                logstashTcpSocketAppender.addDestination(logstashUrl);

                LogstashEncoder encoder = new LogstashEncoder();
                encoder.setIncludeMdc(true);
                encoder.getFieldNames().setLevelValue(null);
                encoder.setCustomFields(String.format("{\"app_name\":\"%s\"}",applicationName));

                logstashTcpSocketAppender.setEncoder(encoder);
                logstashTcpSocketAppender.start();

                loggerContext.getLogger(Logger.ROOT_LOGGER_NAME).addAppender(logstashTcpSocketAppender);                                                                                      ;
            }
        }
    }
}