java - 无法解析值 'message' 中的占位符 "${message}"

Question

我正在实现本指南:https://spring.io/guides/gs/centralized-configuration/关于Spring Cloud配置。

服务器:

@EnableConfigServer
@SpringBootApplication
public class SpringCloudConfigExampleServiceApplication {

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

服务器应用程序.属性:

server.port=8888
spring.cloud.config.server.git.uri=https://github.com/stavalfi/MySpringCloudConfigContentRepository.git

使用 Chrome 进行测试时:(HTTP GET http://localhost:8888/a-bootiful-client/default )

{"name":"a-bootiful-client","profiles":["default"],"label":null,"version":"2a26730fb12930f13d1cc22c01f31e73e7549c8e","state":null,"propertySources":[{"name":"https://github.com/stavalfi/MySpringCloudConfigContentRepository.git/a-bootiful-client.properties","source":{"message":"Hello world"}}]}

如您所见，我得到:{"message":"Hello world"}

客户:

@SpringBootApplication
public class SpringCloudConfigExampleClientApplication {
    @Value("${message}")
    private String message;

    public static void main(String[] args) {
        ConfigurableApplicationContext run = SpringApplication.run(SpringCloudConfigExampleClientApplication.class, args);
        SpringCloudConfigExampleClientApplication bean = run.getBean(SpringCloudConfigExampleClientApplication.class);
        System.out.println(bean.message);
    }
}

客户端应用程序属性:

management.endpoints.web.exposure.include=*
server.port=8889

客户端 Bootstrap .properties:

spring.application.name=a-bootiful-client
# N.B. this is the default:
spring.cloud.config.uri=http://localhost:8888

客户端pom:

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-config</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
</dependencies>

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>Finchley.M8</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

客户端日志:

2018-04-02 16:58:47.179  INFO 12920 --- [           main] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@1ab3a8c8: startup date [Mon Apr 02 16:58:47 IDT 2018]; root of context hierarchy
2018-04-02 16:58:47.572  INFO 12920 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'configurationPropertiesRebinderAutoConfiguration' of type [org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration$$EnhancerBySpringCGLIB$$a73efeaf] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.0.0.RELEASE)

2018-04-02 16:58:49.969  INFO 12920 --- [           main] pringCloudConfigExampleClientApplication : No active profile set, falling back to default profiles: default
2018-04-02 16:58:49.984  INFO 12920 --- [           main] ConfigServletWebServerApplicationContext : Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@127a7a2e: startup date [Mon Apr 02 16:58:49 IDT 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@1ab3a8c8
2018-04-02 16:58:50.725  INFO 12920 --- [           main] o.s.b.f.s.DefaultListableBeanFactory     : Overriding bean definition for bean 'environmentWebEndpointExtension' with a different definition: replacing [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.actuate.autoconfigure.env.EnvironmentEndpointAutoConfiguration; factoryMethodName=environmentWebEndpointExtension; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/actuate/autoconfigure/env/EnvironmentEndpointAutoConfiguration.class]] with [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.cloud.autoconfigure.LifecycleMvcEndpointAutoConfiguration$EndpointConfiguration; factoryMethodName=environmentWebEndpointExtension; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/cloud/autoconfigure/LifecycleMvcEndpointAutoConfiguration$EndpointConfiguration.class]]
2018-04-02 16:58:51.037  INFO 12920 --- [           main] o.s.cloud.context.scope.GenericScope     : BeanFactory id=944851fc-58c8-3037-8f68-7acce53c9e18
2018-04-02 16:58:51.131  INFO 12920 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration' of type [org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration$$EnhancerBySpringCGLIB$$a73efeaf] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2018-04-02 16:58:52.760  INFO 12920 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8889 (http)
2018-04-02 16:58:52.768  INFO 12920 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2018-04-02 16:58:52.769  INFO 12920 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.28
2018-04-02 16:58:52.809  INFO 12920 --- [ost-startStop-1] o.a.catalina.core.AprLifecycleListener   : The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: [C:\Program Files\Java\jdk1.8.0_121\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\Python34\;C:\Python34\Scripts;C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\WebEx\Productivity Tools;C:\Program Files\apache-maven-3.3.9\bin;C:\Program Files\Microsoft SQL Server\110\Tools\Binn\;C:\Program Files\SourceGear\Common\DiffMerge\;C:\ProgramData\chocolatey\bin;C:\Program Files (x86)\Skype\Phone\;C:\Program Files\Spring\spring-1.5.2.RELEASE\bin;C:\Program Files\Microsoft SQL Server\Client SDK\ODBC\110\Tools\Binn\;C:\Program Files (x86)\Microsoft SQL Server\120\Tools\Binn\;C:\Program Files\Microsoft SQL Server\120\Tools\Binn\;C:\Program Files\Microsoft SQL Server\120\DTS\Binn\;C:\Program Files (x86)\Microsoft SQL Server\120\Tools\Binn\ManagementStudio\;C:\Program Files (x86)\Microsoft SQL Server\120\DTS\Binn\;C:\dev\tools\zookeeper-3.4.10\bin;C:\Program Files\MySQL\MySQL Utilities 1.6\;C:\GIT\6.7_rh-backend\deployment\ThirdPartydll;C:\Program Files\Java\jdk1.8.0_144\bin;C:\Program Files (x86)\Gow\bin;C:\opt\spark\spark-2.1.0-bin-hadoop2.7\bin;C:\Program Files\Microsoft SQL Server\130\Tools\Binn\;C:\Program Files\dotnet\;C:\Program Files\Java\jdk1.8.0_144\bin;C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\Common7\IDE\;C:\Program Files\nodejs\;C:\Windows\System32\inetsrv\;C:\Program Files\Microsoft\Web Platform Installer\;C:\Program Files\Git\cmd;C:\Program Files (x86)\Windows Live\Shared;C:\ProgramData\chocolatey\lib\elasticsearch\tools\elasticsearch-5.2.0\bin;C:\Users\stava\AppData\Roaming\npm;C:\Program Files (x86)\Nmap;.]
2018-04-02 16:58:53.043  INFO 12920 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2018-04-02 16:58:53.043  INFO 12920 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 3059 ms
2018-04-02 16:58:54.392  INFO 12920 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Servlet dispatcherServlet mapped to [/]
2018-04-02 16:58:54.392  INFO 12920 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2018-04-02 16:58:54.392  INFO 12920 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2018-04-02 16:58:54.392  INFO 12920 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2018-04-02 16:58:54.392  INFO 12920 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2018-04-02 16:58:54.392  INFO 12920 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpTraceFilter' to: [/*]
2018-04-02 16:58:54.392  INFO 12920 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'webMvcMetricsFilter' to: [/*]
2018-04-02 16:58:54.455  WARN 12920 --- [           main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'springCloudConfigExampleClientApplication': Injection of autowired dependencies failed; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'message' in value "${message}"
2018-04-02 16:58:54.455  INFO 12920 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2018-04-02 16:58:54.486  INFO 12920 --- [           main] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2018-04-02 16:58:54.486 ERROR 12920 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'springCloudConfigExampleClientApplication': Injection of autowired dependencies failed; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'message' in value "${message}"
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:379) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1344) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:502) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:312) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:310) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:760) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:868) ~[spring-context-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:388) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1246) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1234) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
    at com.nice.spring.cloud.config.example.client.SpringCloudConfigExampleClientApplication.main(SpringCloudConfigExampleClientApplication.java:14) [classes/:na]
Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder 'message' in value "${message}"
    at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:172) ~[spring-core-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.util.PropertyPlaceholderHelper.replacePlaceholders(PropertyPlaceholderHelper.java:124) ~[spring-core-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.core.env.AbstractPropertyResolver.doResolvePlaceholders(AbstractPropertyResolver.java:237) ~[spring-core-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.core.env.AbstractPropertyResolver.resolveRequiredPlaceholders(AbstractPropertyResolver.java:211) ~[spring-core-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.context.support.PropertySourcesPlaceholderConfigurer.lambda$processProperties$0(PropertySourcesPlaceholderConfigurer.java:175) ~[spring-context-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.resolveEmbeddedValue(AbstractBeanFactory.java:834) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1086) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1065) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:584) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:91) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:373) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    ... 17 common frames omitted


Process finished with exit code 1

项目的 Github 存储库:

https://github.com/stavalfi/spring-cloud-config-example

Answer 1

我猜你忘记了演示的一部分

Add a simple property and value, message = Hello world, to the newly created a-bootiful-client.properties file and then git commit the change

也许此时属性尚未加载。您下面的示例略有不同

@SpringBootApplication
public class ConfigClientApplication {

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

@RefreshScope
@RestController
class MessageRestController {

@Value("${message:Hello default}")
 private String message;

  @RequestMapping("/message")
  String getMessage() {
    return this.message;
  }
}

消息将在 Controller 中填充/刷新