Question

我希望 log4j2-spring.xml 从 application.properties 文件中读取一个属性。但似乎 log4j2-spring.xml 无法读取此内容。我已阅读 https://logging.apache.org/log4j/2.x/manual/lookups.html#SpringLookup 来实现这一点。

我在本网站上看到了 this answer。也这样试过。但这对我没有帮助。

我的 build.gradle 是这样的：

plugins {
    id 'org.springframework.boot' version '2.5.0-SNAPSHOT'
    id 'io.spring.dependency-management' version '1.0.11.RELEASE'
    id 'java'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
    mavenCentral()
    maven { url 'https://repo.spring.io/milestone' }
    maven { url 'https://repo.spring.io/snapshot' }
}

ext {
    log4j2version = '2.14.1'
}

dependencies {

    compileOnly 'org.projectlombok:lombok:1.18.18'
    annotationProcessor 'org.projectlombok:lombok:1.18.18'

    implementation 'org.springframework.boot:spring-boot-starter'
    implementation 'org.springframework.boot:spring-boot-starter-log4j2'

    implementation "org.apache.logging.log4j:log4j-spring-cloud-config-client:${log4j2version}"
    implementation "org.apache.logging.log4j:log4j-api:${log4j2version}"
    implementation "org.apache.logging.log4j:log4j-core:${log4j2version}"
}

configurations {
    all {
        exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
        exclude group: "ch.qos.logback", module: "logback-classic"
        exclude group: "org.springframework.cloud", module: "spring-cloud-bus"
    }
}

application.properties 文件是：

commission.base.path1=C:/Users/user1/Downloads/demo1
logging.config=classpath:log4j2-spring.xml

spring.cloud.config.enabled=false

log4j2-spring.xml 是这样的：

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    
    <Appenders>
        <Console name="console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss:SSS} [%thread] %-5level %logger{2}:%L - %msg%n"/>
        </Console>

        <RollingFile name="CATALINA-FILE" fileName="$${spring:commission.base.path1}/logs/catalina.log"
                     filePattern="$${spring:commission.base.path1}/logs/archived/catalina_%d{yyyy-MM-dd}.log.gz">
            <PatternLayout>
                <Pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{20}:%L - %msg%n</Pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy interval="1"/>
                <SizeBasedTriggeringPolicy size="1 GB" />
            </Policies>
        </RollingFile>
    </Appenders>

    <Loggers>
        <root level="debug">
            <appender-ref ref="CATALINA-FILE"/>
            <appender-ref ref="console"/>
        </root>
    </Loggers>
</configuration>

但是每次我运行代码时，我都会收到这个异常：

2021-05-21 21:28:38,409 main ERROR Unable to create file ${spring:commission.base.path1}/logs/catalina.log java.io.IOException: The filename, directory name, or volume label syntax is incorrect
    at java.io.WinNTFileSystem.canonicalize0(Native Method)
    at java.io.WinNTFileSystem.canonicalize(WinNTFileSystem.java:428)
    at java.io.File.getCanonicalPath(File.java:618)
    at java.io.File.getCanonicalFile(File.java:643)
    at org.apache.logging.log4j.core.util.FileUtils.makeParentDirs(FileUtils.java:135)
    at org.apache.logging.log4j.core.appender.rolling.RollingFileManager$RollingFileManagerFactory.createManager(RollingFileManager.java:720)
    at org.apache.logging.log4j.core.appender.rolling.RollingFileManager$RollingFileManagerFactory.createManager(RollingFileManager.java:704)
    at org.apache.logging.log4j.core.appender.AbstractManager.getManager(AbstractManager.java:113)
    at org.apache.logging.log4j.core.appender.OutputStreamManager.getManager(OutputStreamManager.java:100)
    at org.apache.logging.log4j.core.appender.rolling.RollingFileManager.getFileManager(RollingFileManager.java:217)
    at org.apache.logging.log4j.core.appender.RollingFileAppender$Builder.build(RollingFileAppender.java:146)
    at org.apache.logging.log4j.core.appender.RollingFileAppender$Builder.build(RollingFileAppender.java:62)
    at org.apache.logging.log4j.core.config.plugins.util.PluginBuilder.build(PluginBuilder.java:122)
    at org.apache.logging.log4j.core.config.AbstractConfiguration.createPluginObject(AbstractConfiguration.java:1000)
    at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:940)
    at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:932)
    at org.apache.logging.log4j.core.config.AbstractConfiguration.doConfigure(AbstractConfiguration.java:551)
    at org.apache.logging.log4j.core.config.AbstractConfiguration.initialize(AbstractConfiguration.java:241)
    at org.apache.logging.log4j.core.config.AbstractConfiguration.start(AbstractConfiguration.java:287)
    at org.apache.logging.log4j.core.LoggerContext.setConfiguration(LoggerContext.java:627)
    at org.apache.logging.log4j.core.LoggerContext.start(LoggerContext.java:304)
    at org.apache.logging.log4j.spring.boot.Log4j2CloudConfigLoggingSystem.loadConfiguration(Log4j2CloudConfigLoggingSystem.java:123)
    at org.springframework.boot.logging.log4j2.Log4J2LoggingSystem.loadConfiguration(Log4J2LoggingSystem.java:181)
    at org.springframework.boot.logging.AbstractLoggingSystem.initializeWithConventions(AbstractLoggingSystem.java:80)
    at org.springframework.boot.logging.AbstractLoggingSystem.initialize(AbstractLoggingSystem.java:60)
    at org.springframework.boot.logging.log4j2.Log4J2LoggingSystem.initialize(Log4J2LoggingSystem.java:163)
    at org.apache.logging.log4j.spring.boot.Log4j2CloudConfigLoggingSystem.initialize(Log4j2CloudConfigLoggingSystem.java:80)
    at org.springframework.boot.context.logging.LoggingApplicationListener.initializeSystem(LoggingApplicationListener.java:312)
    at org.springframework.boot.context.logging.LoggingApplicationListener.initialize(LoggingApplicationListener.java:281)
    at org.springframework.boot.context.logging.LoggingApplicationListener.onApplicationEnvironmentPreparedEvent(LoggingApplicationListener.java:239)
    at org.springframework.boot.context.logging.LoggingApplicationListener.onApplicationEvent(LoggingApplicationListener.java:216)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:176)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:169)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:143)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:131)
    at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:82)
    at org.springframework.boot.SpringApplicationRunListeners.lambda$environmentPrepared$2(SpringApplicationRunListeners.java:63)
    at java.util.ArrayList.forEach(ArrayList.java:1259)
    at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:117)
    at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:111)
    at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:62)
    at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:373)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:331)
    at org.springframework.boot.builder.SpringApplicationBuilder.run(SpringApplicationBuilder.java:144)
    at org.springframework.cloud.bootstrap.BootstrapApplicationListener.bootstrapServiceContext(BootstrapApplicationListener.java:212)
    at org.springframework.cloud.bootstrap.BootstrapApplicationListener.onApplicationEvent(BootstrapApplicationListener.java:117)
    at org.springframework.cloud.bootstrap.BootstrapApplicationListener.onApplicationEvent(BootstrapApplicationListener.java:74)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:176)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:169)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:143)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:131)
    at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:82)
    at org.springframework.boot.SpringApplicationRunListeners.lambda$environmentPrepared$2(SpringApplicationRunListeners.java:63)
    at java.util.ArrayList.forEach(ArrayList.java:1259)
    at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:117)
    at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:111)
    at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:62)
    at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:373)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:331)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1336)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1325)
    at com.example.demo1.Demo1Application.main(Demo1Application.java:12)

如何解决这个问题？提前致谢。

Answer 1

问题是你需要在 Spring Cloud 上配置 Log4j 吗？

问题

如果没有，我会说 org.apache.logging.log4j:2.14.1 依赖是一种矫枉过正。它带来了您不需要的 Spring Cloud 依赖项。以我仍然没有弄清楚的方式，它还会干扰 spring-boot-starter-log4j2 导致多次初始化日志上下文，然后作为副作用，您在启动时会遇到这种情况来自 Spring 的属性未解析。

解决方案

请注意，您不需要整个 log4j-spring-cloud-config-client 甚至 spring-boot-starter-log4j2。

以下依赖项将设置您的日志记录上下文：

log4j
log4j-slf4j-impl
log4j-spring-boot

我放了一个 example program in GitHub repository。变量名称略有更改，并有注释解释每个依赖项的用途。

Gradle 构建文件摘录

dependencies {

  compileOnly 'org.projectlombok:lombok:1.18.18'
  annotationProcessor 'org.projectlombok:lombok:1.18.18'

  // Spring Boot dependency
  implementation 'org.springframework.boot:spring-boot-starter'
  testImplementation 'org.springframework.boot:spring-boot-starter-test'

  // Logging dependencies

  // Base Log4j 2
  implementation "org.apache.logging.log4j:log4j-api:${log4j2version}"

  // Will resolve spring properties
  implementation "org.apache.logging.log4j:log4j-spring-boot:${log4j2version}"

  // Log4j 2 to Slf4j binder
  implementation "org.apache.logging.log4j:log4j-slf4j-impl:${log4j2version}"
}

Official documentation 应该说 log4j-spring-boot 依赖项足以解析 Spring 配置文件中的查找变量。

但是，如果您真的需要通过云配置来配置 Log4J，那么您必须再次仔细查看依赖项是如何解决的，以及您真正需要哪些依赖项。

Answer 2

我刚刚添加

<块引用>

实现“org.apache.logging.log4j:log4j-spring-boot”

在 build.gradle 中，它现在可以工作了。

实施

<块引用>

实现'org.springframework.boot:spring-boot-starter-log4j2'

足以使用 log4j2 版本 2.14.1，因为 Spring Boot 版本是 2.5.0-SNAPSHOT。无需为此显式添加 org.apache.logging.log4j 的依赖项。

所以我最终的 build.gradle 是：

export function userFacingLibraryFunction<T extends ValidSomeShape<T>>(someShape: T): void {
  // now that someShape has been validated, we can pass it to our internal functions:
  internalLibraryFunction(someShape);
}

// not exported
function internalLibraryFunction(alreadyValidatedSomeShape: Record<string, boolean>): void {  
  Object.keys(alreadyValidatedSomeShape).filter(k => alreadyValidatedSomeShape[k]);
}

并且不需要需要将其保留在application.properties中：

var components = [component1, component2, component3, component4]
var dots = []
for (var i = 0; i < 17; ++i) dots.push(components[_.random(3)]);

是的，Official Documentation of log4j 应该添加 log4j-spring-boot 依赖项足以实现 spring 查找。

log4j2 spring boot 查找无法从 application.properties 读取属性

2 个答案: