Spring Boot Environment From file config

Spring Boot Environment From file config

主要流程

1. ​​SpringApplication​​​ run -> ​​ApplicationEnvironmentPreparedEvent​​
2. ​​ApplicationEnvironmentPreparedEvent​​​ ->​​EnvironmentPostProcessor​​
3. ​​EnvironmentPostProcessor​​​(​​ConfigFileApplicationListener​​) ->Load (​​application.yml​​ …)

Load Config

Load ​​application.yml​​​ … from ​​classpath:/,classpath:/config/,file:./,file:./config/​​

优先级逆序… ​​StringUtils.commaDelimitedListToStringArray​​​ ​​Collections.reverse(list);​​

1. query load profiles from

• JVM arguments:​​spring.profiles.active​​​ |​​spring.profiles.include​​
• Search Location || Load Location
• Load For​​prefix(location) + name + fileExtension​​
• ResourceLoader.getResource(Location)
• 顺序加载 application ->​​spring.profiles.active​​
• load DocumentsCache loaded
• 逆序DocumentsCache 然后逆序加载所有config file

Search Location

/**
   * The "config location" property name.
   */
  public static final String CONFIG_LOCATION_PROPERTY = "spring.config.location";

  /**
   * The "config additional location" property name.
   */
  public static final String CONFIG_ADDITIONAL_LOCATION_PROPERTY = "spring.config.additional-location";

        private Set<String> getSearchLocations() {
            //如果当前的Environment有spring.config.location 此时application.yml尚未加载哦!
      if (this.environment.containsProperty(CONFIG_LOCATION_PROPERTY)) {
        return getSearchLocations(CONFIG_LOCATION_PROPERTY);
      }
            //如果当前的Environment有spring.config.additional-location 则加载
            //Set<String> locations = new LinkedHashSet<>();
      Set<String> locations = getSearchLocations(
          CONFIG_ADDITIONAL_LOCATION_PROPERTY);
            //add `classpath:/,classpath:/config/,file:./,file:./config/`
      locations.addAll(
          asResolvedSet(ConfigFileApplicationListener.this.searchLocations,
              DEFAULT_SEARCH_LOCATIONS));
      return locations;
    }

模拟从classpath || file 加载文件

@Autowired
    private ResourceLoader resourceLoader;

     //或者new DefaultResourceLoader();
    private Resource getResource(ResourceLoader resourceLoader, String[] certificatePath, String fileName) {
        for (int i = certificatePath.length - 1; i >= 0; i--) {
            Resource resource = resourceLoader.getResource(certificatePath[i] + fileName);
            if (resource.exists()) {
                return resource;
            }
        }
        throw new ResourceRequestDeniedException(fileName + "资源未找到");
    }