Question

我有一个spring boot Web应用程序，它只打印一个在Kubernetes的ConfigMap中传递的属性。

这是我的主要课程：

@SpringBootApplication
@EnableDiscoveryClient
@RestController
public class DemoApplication {

    private MyConfig config;
    private DiscoveryClient discoveryClient;

    @Autowired
    public DemoApplication(MyConfig config, DiscoveryClient discoveryClient) {
        this.config = config;
        this.discoveryClient = discoveryClient;
    }

    @RequestMapping("/")
    public String info() {
        return config.getMessage();
    }

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

    @RequestMapping("/services")
    public String services() {
        StringBuilder b = new StringBuilder();
        discoveryClient.getServices().forEach((s) -> b.append(s).append(" , "));
        return b.toString();
    }

}

和MyConfig类是：

@Configuration
@ConfigurationProperties(prefix = "bean")
public class MyConfig {

    private String message = "a message that can be changed live";

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }
}

基本上，通过调用根资源，我总是得到：

可以实时更改的消息

然后调用/ services，我实际上得到了Kubernetes服务的列表。

我正在以kubectl create -f configmap-demo.yml作为内容创建ConfigMap：

apiVersion: v1
kind: ConfigMap
metadata:
  name: demo
data:
    bean.message: This is an info from k8

部署kubecetl create -f deploy-demo.yml，其内容为：

apiVersion: apps/v1
kind: Deployment
metadata:
  name: demo
  labels:
    app: demo
spec:
  replicas: 1
  selector:
    matchLabels:
      app: demo
  template:
    metadata:
      labels:
        app: demo
    spec:
      # this service account was created according to
      # https://kubernetes.io/docs/reference/access-authn-authz/rbac/#service-account-permissions
      # point 5 - Grant super-user access to all service accounts cluster-wide (strongly discouraged)
      serviceAccountName: i18n-spring-k8
      containers:
      - name: demo
        image: aribeiro/sck-demo
        imagePullPolicy: Never
        env:
        - name: JAVA_OPTS
          value:
        ports:
        - containerPort: 8080
      volumes:
      - name: demo
        configMap:
          name: demo

问题是，当访问根资源/时，我总是得到默认的硬编码值，而从来没有得到Kubernetes的ConfigMap中定义的值。

示例项目也包含https://drive.google.com/open?id=107IcwnYIbVpmwVgdgi8Dhx4nHEFAVxV8上可用的yaml文件和Docker文件。

还检查了启动DEBUG日志，但没有看到任何错误或线索为什么它不起作用。

Answer 1

Spring Cloud Kubernetes documentation不完整。它缺少包含此依赖项以启用从ConfigMap加载应用程序属性的说明：

<dependency>
  <groupId>org.springframework.cloud</groupId>
  <artifactId>spring-cloud-starter-kubernetes-config</artifactId>
</dependency>

Answer 2

您很亲密：

1）稍微定义ConfigMap，以便它包含属性文件。例如：

apiVersion: v1
kind: ConfigMap
metadata:
  name: demo
data:
  demo.properties: |
    bean.message: This is an info from k8

2）将ConfigMap挂载为卷：

...
spec:
  containers:
  - name: demo
    ...
    volumeMounts:
    - name: config
      mountPath: /demo/config
  volumes:
  - name: config
    configMap:
      name: demo

结果，在ConfigMap中定义的demo.properties文件将“出现”在运行容器的/demo/config目录中。

3）在@PropertySource类中添加MyConfig注释：

@Configuration
@PropertySource("file:/demo/config/demo.properties")
@ConfigurationProperties(prefix = "bean")
public class MyConfig {
  ...
}

Spring Cloud Kubernetes-Spring Boot不读取配置映射

2 个答案: