变量未被读取为系统属性

Question

我试图从系统属性中读取我的 logback 配置中的变量，但没有成功。我定义了一个非常简单的 logback.groovy 如下：

import ch.qos.logback.classic.encoder.PatternLayoutEncoder
import ch.qos.logback.core.FileAppender

import static ch.qos.logback.classic.Level.DEBUG

appender("FILE", FileAppender) {
  file = "${USER_HOME}/myApp.log"
  encoder(PatternLayoutEncoder) {
    pattern = "%msg%n" 
  }
}
root(DEBUG, ["FILE"])

然后一个简单的Test.scala:

import org.slf4j.LoggerFactory

object Test {

        val log = LoggerFactory.getLogger(getClass)

        def main(args: Array[String]): Unit = {

                log.debug("Where does the logging go?")

        }
}

然后运行

sbt -DUSER_HOME="/tmp"

但是 logback 不获取系统属性。下面是我运行程序时的输出：

22:03:30,768 |-INFO in ch.qos.logback.classic.LoggerContext[default] - Found resource [logback.groovy] at [file:/home/des/workspace/play/target/scala-2.10/classes/logback.groovy] 22:03:31,449 |-INFO in ch.qos.logback.classic.gaffer.ConfigurationDelegate@5c3286d0 - About to instantiate appender of type [ch.qos.logback.core.FileAppender] 22:03:31,450 |-INFO in ch.qos.logback.classic.gaffer.ConfigurationDelegate@5c3286d0 - Naming appender as [FILE] 22:03:31,515 |-ERROR in ch.qos.logback.classic.gaffer.AppenderDelegate@7930f0f9 - Appender [FILE] of type [ch.qos.logback.core.FileAppender] has no appplicable [USER_HOME] property 22:03:31,556 |-INFO in ch.qos.logback.core.FileAppender[FILE] - File property is set to [null/myApp.log] 22:03:31,562 |-INFO in ch.qos.logback.classic.gaffer.ConfigurationDelegate@5c3286d0 - Setting level of logger [ROOT] to DEBUG 22:03:31,569 |-INFO in ch.qos.logback.classic.gaffer.ConfigurationDelegate@5c3286d0 - Attaching appender named [FILE] to Logger[ROOT]

请注意，当我在我的 logback 文件中定义 USER_HOME 时，它工作正常

Answer 1

您需要执行以下操作

sbt '; set javaOptions += "-DUSER_HOME="/tmp" ; runMain Test'

或

更改您的 build.sbt 以包含

fork := true

envVars := Map("USER_HOME" -> "/tmp")

如果您想从生产环境运行不使用 sbt，您可以直接将其传递（使用 -DUSER_HOME="/tmp"）到运行创建 Play 分发（使用 dist）命令时生成的脚本。

Answer 2

因为我正在使用groovy。认为这是一个 logback 错误，我这样报告并解决了：http://jira.qos.ch/browse/LOGBACK-1041

变量未被读取为系统属性

Variable not being read as a system property

groovy

scala

logback