Java Spring Boot@ConditionalOnProperty未动态设置属性

我有一个Spring启动应用程序和一个外部库。应用程序导入库。库中有一个@Configuration类，该类根据此属性的值有条件地加载。 我使用的是Spring Boot 2.2.6

相关类别如下所示：

@Configuration
@ConditionalOnProperty(prefix = "custom", name = "enabled", havingValue = "true")
public class LibraryTrueConfiguration {

    // Load the Beans

}

应用程序的主类：

@Import(SharedLibConfiguration .class)
@SpringBootApplication
public class ServiceApp {

    public static void main(final String[] args) {
        SpringApplication.run(ServiceApp.class, args);
    }

}

在应用程序的下面配置中动态设置属性，这些属性集不会由库反映以加载相关配置

如果我的application.yml有custom.enabled=false，并且我在下面的代码中设置custom.enabled=true，则不会在正在加载的配置文件库中反映出来。正在加载自定义的文件。enabled=false

@Configuration
public class DynamicPropsConfig {

  // Service which fetch dynamic properties from DB
  @Autowired
  DynamicPropsLoader dynamicPropsLoader;
  @Autowired
  CustomProperties customProperties;
  
  @DependsOn("dynamicPropsLoader")
  @Autowired
  void setDynamicPropertiesInEnvironment(ConfigurableEnvironment environment) {
    System.out.println("[Before]customProperties = " + customProperties);

      environment.getPropertySources().addFirst(new MapPropertySource("custom",
          dynamicPropsLoader.getCustomPropertiesMap()));

    final HashMap<Object, Object> customPropertiesMap = dynamicPropsLoader
        .getCustomPropertiesMap().keySet()
        .stream()
        .collect(HashMap::new, (m, v) -> m.put(v, environment.getProperty(v)), HashMap::putAll);
    System.out.println("[After]customPropertiesMap = " + customPropertiesMap);

  }

}

---

这帮助我解决了这个问题。我们需要使用EnvironmentPostProcessor和前面提到的META-INF/spring.factories文件

@Import(SharedLibConfiguration .class)
@SpringBootApplication
public class ServiceApp {

    public static void main(final String[] args) {
        SpringApplication.run(ServiceApp.class, args);
    }

}

@Configuration
public class DynamicPropsConfig {

  // Service which fetch dynamic properties from DB
  @Autowired
  DynamicPropsLoader dynamicPropsLoader;
  @Autowired
  CustomProperties customProperties;
  
  @DependsOn("dynamicPropsLoader")
  @Autowired
  void setDynamicPropertiesInEnvironment(ConfigurableEnvironment environment) {
    System.out.println("[Before]customProperties = " + customProperties);

      environment.getPropertySources().addFirst(new MapPropertySource("custom",
          dynamicPropsLoader.getCustomPropertiesMap()));

    final HashMap<Object, Object> customPropertiesMap = dynamicPropsLoader
        .getCustomPropertiesMap().keySet()
        .stream()
        .collect(HashMap::new, (m, v) -> m.put(v, environment.getProperty(v)), HashMap::putAll);
    System.out.println("[After]customPropertiesMap = " + customPropertiesMap);

  }

}

@Component
public class DynamicCustomPropsClr implements CommandLineRunner {

  @Autowired
  Environment environment;
  @Autowired
  ConfigurableEnvironment configurableEnvironment;
  @Value("${custom.enabled:}")
  String customEnabled;

  @Override
  public void run(String... args) throws Exception {
    System.out.println("environment.getProperty(\"custom.enabled\") = " + environment
        .getProperty("custom.enabled"));
    System.out.println(
        "configurableEnvironment.getProperty(\"custom.enabled\") = " + configurableEnvironment
            .getProperty("custom.enabled"));
    System.out.println("customenabled = " + customenabled);
  }
}

output
------
environment.getProperty("custom.enabled") = true
configurableEnvironment.getProperty("custom.enabled") = true
customEnabled = false