Spring Cloud Kubernetes - Spring 启动时未读取配置映射

Question

我有一个 spring 启动网络应用程序，它只打印一个属性在 Kubernetes 的 ConfigMap 中传递的

这是我的主class:

@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();
    }

}

而 MyConfig class 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：

a message that can be changed live

然后调用 /services 我实际上得到了 Kubernetes 服务列表。

我正在创建内容为 kubectl create -f configmap-demo.yml 的 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 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

问题是在访问根资源时 / 我总是得到默认的硬编码值，而不是 Kubernetes 的 ConfigMap 中定义的值。

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

还检查了启动 DEBUG 日志，我没有看到任何错误或线索为什么它不应该工作。

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指令：

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

Answer 2

你很接近：

1) 对 ConfigMap 的定义略有不同，因此它包含一个属性文件。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

因此，ConfigMap 中定义的 demo.properties 文件将 "appear" 在运行容器内的 /demo/config 目录中。

3) 添加@PropertySource注解到MyConfig class:

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

Spring Cloud Kubernetes - Spring 启动时未读取配置映射

Spring Cloud Kubernetes - Spring boot not reading config map

spring

spring-boot

kubernetes

configmap

spring-cloud-kubernetes