logback-spring 占位符无法被替换

[seqwait]

1. apollo-client: 0.10.0
2. application.properties

   apollo.bootstrap.enabled = true

3. apollo 配置中属性

   log.path = /data/logs/boot/

4. logback ${log.path} 无法被替换 目录为: log.path_IS_UNDEFINED

   <?xml version="1.0"?>
   <configuration>
   <springProperty scope="context" name="log.path" source="log.path"/>
   <property name="LOGS" value="${log.path}"/>
   <appender name="RollingFile" class="ch.qos.logback.core.rolling.RollingFileAppender">
       <file>${LOGS}/boot.log</file>
       <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
           <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
       </encoder>
       <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
           <fileNamePattern>${LOGS}/boot-%d{yyyy-MM-dd}.log.gz</fileNamePattern>
           <maxHistory>20</maxHistory>
           <CleanHistoryOnStart>true</CleanHistoryOnStart>
       </rollingPolicy>
   </appender>
   <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
       <layout class="ch.qos.logback.classic.PatternLayout">
           <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
       </layout>
   </appender>
   <root level="info">
       <appender-ref ref="STDOUT"/>
       <appender-ref ref="RollingFile"/>
   </root>
   </configuration>

[nobodyiam]

duplicated with https://github.com/ctripcorp/apollo/issues/3855