覆盖Spring Cloud配置值与环境

Question

有没有办法覆盖通过Spring Cloud Config Server与其他属性源（特别是系统环境）设置的属性？我知道我可以通过循环访问Environment对象的PropertySource来手动执行此操作，但是如果我可以将其设置为bootstrapConfig来源为最低优先级，那将是理想的。

Answer 1

FWIW，我通过编写一个自定义的ApplicationListener来完成这个任务，这个自定义的事件在周期早期被触发，但是在配置服务的PropertySource被加载后。我附上了代码，以防万一有兴趣。如果有一个“官方”春办法做到这一点，我仍然有兴趣，但这个工程：

package com.example; 

import org.springframework.boot.context.event.ApplicationPreparedEvent; 
import org.springframework.context.ApplicationListener; 
import org.springframework.core.Ordered; 
import org.springframework.core.annotation.Order; 
import org.springframework.core.env.CompositePropertySource; 
import org.springframework.core.env.ConfigurableEnvironment; 
import org.springframework.core.env.MutablePropertySources; 
import org.springframework.core.env.PropertySource; 

@Order(Ordered.HIGHEST_PRECEDENCE) 
public class ConfigServicePropertyDeprioritizer 
     implements ApplicationListener<ApplicationPreparedEvent> 
{ 
    private static final String CONFIG_SOURCE = "bootstrap"; 

    private static final String PRIORITY_SOURCE = "systemEnvironment"; 

    @Override 
    public void onApplicationEvent(ApplicationPreparedEvent event) 
    { 
     ConfigurableEnvironment environment = event.getApplicationContext() 
       .getEnvironment(); 
     MutablePropertySources sources = environment.getPropertySources(); 
     PropertySource<?> bootstrap = findSourceToMove(sources); 

     if (bootstrap != null) 
     { 
      sources.addAfter(PRIORITY_SOURCE, bootstrap); 
     } 
    } 

    private PropertySource<?> findSourceToMove(MutablePropertySources sources) 
    { 
     boolean foundPrioritySource = false; 

     for (PropertySource<?> source : sources) 
     { 
      if (PRIORITY_SOURCE.equals(source.getName())) 
      { 
       foundPrioritySource = true; 
       continue; 
      } 

      if (CONFIG_SOURCE.equals(source.getName())) 
      { 
       // during bootstrapping, the "bootstrap" PropertySource 
       // is a simple MapPropertySource, which we don't want to 
       // use, as it's eventually removed. The real values will 
       // be in a CompositePropertySource 
       if (source instanceof CompositePropertySource) 
       { 
        return foundPrioritySource ? null : source; 
       } 
      } 
     } 

     return null; 
    } 
}