5.2 Building our Spring Cloud configuration server

5.2.2 Using Spring Cloud configuration server with the filesystem

依赖

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>    
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-config-server</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-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

基本配置文件

spring:
  application:
    name: config-server
server:
  port: 8071

基于文件系统存储的配置
native：表示配置文件将从classpath或filesystem中获取

spring:
  application:
    name: config-server
  profiles:
    active: native
  cloud:
    config:
      server:
        native:
          search-locations:
            - file:///Users/illary.huaylupo
server:
  port: 8071

    server:
        native:
          search-locations:
            - classpath:/config

5.2.3 Setting up the configuration files for a service

在resources下创建config目录，并添加两个properties文件，如下图

example.property= I AM THE DEFAULT
spring.jpa.hibernate.ddl-auto=none
spring.jpa.database=POSTGRESQL
spring.datasource.platform=postgres
spring.jpa.show-sql = true
spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.PostgreSQLDialect
spring.database.driverClassName= org.postgresql.Driver
spring.datasource.testWhileIdle = true
spring.datasource.validationQuery = SELECT 1
management.endpoints.web.exposure.include=*
management.endpoints.enabled-by-default=true

example.property= I AM DEV
# DataSource settings: set here your own configurations for the database
spring.datasource.url = jdbc:postgresql://101.132.251.198:5432/test
spring.datasource.username = postgres
spring.datasource.password = root

启动项目并访问：http://localhost:8071/licensing-service/default

如果访问：http://localhost:8071/licensing-service/dev

查找dev的时候，会把default的属性一起查找出来，这是因为spring有个等级机制，当查找配置文件的时候，总是会优先找default的配置文件，然后再找相应的特定环境的文件，如果有属性冲突，就会覆盖默认的。

5.3 Integrating Spring Cloud Config with a Spring Boot Client

5.3.1 Setting up the licensing service spring cloud config service dependencies

添加依赖

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-config</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <version>42.3.1</version>
        </dependency>
    </dependencies>

5.3.2 Configuration the licensing service to use Spring Cloud Config

配置文件

spring:
  application:
    name:
      licensing-service
  profiles:
    active: dev
  cloud:
    config:
      uri: http://localhost:8071

启动项目并访问：http://localhost:8080/actuator/env

5.3.3 Wiring in a data source using Spring Cloud configuration server

引入依赖：

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-hateoas</artifactId>
        </dependency>

实体类：

@Data
@Entity
@Table(name = "licenses")
public class License extends RepresentationModel<License> {
    @Id
    @Column(name = "license_id", nullable = false)
    private String licenseId;
    private String description;
    @Column(name = "organization_id", nullable = false)
    private String organizationId;
    @Column(name = "product_name", nullable = false)
    private String productName;
    @Column(name = "license_type", nullable = false)
    private String licenseType;
    @Column(name = "comment")
    private String comment;
    public License withComment(String comment) {
        this.setComment(comment);
        return this;
    }
}

如果java类中的属性和数据库中表的字段属性相同，就可以不加@Column 注解

LicenseRepository interface定义：

@Repository
public interface LicenseRepository extends CrudRepository<License, String> {
    List<License> findByOrganizationId(String organizationId);
    License findByOrganizationIdAndLicenseId(String organizationId, String licenseId);
}

LicenseService定义：

@Service
public class LicenseService {
    @Autowired
    MessageSource messageSource;
    @Autowired
    private LicenseRepository licenseRepository;
    @Autowired
    ServiceConfig config;
    public License getLicense(String licenseId, String organizationId) {
        License license = licenseRepository.findByOrganizationIdAndLicenseId(licenseId, organizationId);
        if (null == license) {
            throw new IllegalArgumentException(String.format(messageSource.getMessage("license.search.error.message", null, null), licenseId, organizationId));
        }
        return license.withComment(config.getExampleProperty());
    }
    public License updateLicense(License license) {
        licenseRepository.save(license);
        return license.withComment(config.getExampleProperty());
    }
    public String deleteLicense(String licenseId) {
        String responseMessage = null;
        License license = new License();
        license.setLicenseId(licenseId);
        licenseRepository.delete(license);
        responseMessage = String.format(messageSource.getMessage("license.delete.message", null, null), licenseId);
        return responseMessage;
    }
}

5.3.4 Directly reading properties using the @Value annotation

上述代码中引用了config.getExampleProperty()方法

public License updateLicense(License license) {
        licenseRepository.save(license);
        return license.withComment(config.getExampleProperty());
    }

该方法的细节：

@Component
public class ServiceConfig {
    @Value("${example.property}")
    private String exampleProperty;
    public String getExampleProperty() {
        return exampleProperty;
    }
}

5.3.5 Refreshing your properties using Spring Cloud configuration server

为了改变配置的时候，动态的做出反应，需要在启动类上添加一个@RefreshScope

@SpringBootApplication
@RefreshScope
public class LicensingApplication {
    public static void main(String[] args) {
        SpringApplication.run(LicensingApplication.class, args);
    }
}

@RefreshScope该注解只会动态加载在配置文件中自定义的属性，像database configuration这样的配置不会动态的加载。为了执行refresh其他的属性，可以访问
http://:8080/refresh 端点

5.3.6 Using Spring Cloud configuration server with Git

在配置服务中的bootstrap.yml中添加：

5.4 Protecting sensitive configuration information

5.4.1 Setting up a symmetric encryption key

在配置服务模块的bootstrap.yml中添加：

5.4.2 Encrypting and decrypting a property

根据上述的步骤，可以将配置文件中需要加密的属性值加密

{cipher}告诉spring cloud配置服务，处理的是一个加密的值