Dubbo参数验证

一时失言乱红尘 2024-04-17 22:52 79阅读 0赞

参数验证功能 \[备注1\] 是基于 JSR303 实现的，用户只需标识 JSR303 标准的验证 annotation，并通过声明 filter 来实现验证 \[备注2\] 。

## Maven 依赖 ##

<dependency>
        <groupId>javax.validation</groupId>
        <artifactId>validation-api</artifactId>
        <version>1.0.0.GA</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-validator</artifactId>
        <version>4.2.0.Final</version>
    </dependency>

# #

## 示例 ##

### 参数标注示例 ###

import java.io.Serializable;
    import java.util.Date;
     
    import javax.validation.constraints.Future;
    import javax.validation.constraints.Max;
    import javax.validation.constraints.Min;
    import javax.validation.constraints.NotNull;
    import javax.validation.constraints.Past;
    import javax.validation.constraints.Pattern;
    import javax.validation.constraints.Size;
     
    public class ValidationParameter implements Serializable {
        private static final long serialVersionUID = 7158911668568000392L;
     
        @NotNull // 不允许为空
        @Size(min = 1, max = 20) // 长度或大小范围
        private String name;
     
        @NotNull(groups = ValidationService.Save.class) // 保存时不允许为空，更新时允许为空 ，表示不更新该字段
        @Pattern(regexp = "^\\s*\\w+(?:\\.{0,1}[\\w-]+)*@[a-zA-Z0-9]+(?:[-.][a-zA-Z0-9]+)*\\.[a-zA-Z]+\\s*$")
        private String email;
     
        @Min(18) // 最小值
        @Max(100) // 最大值
        private int age;
     
        @Past // 必须为一个过去的时间
        private Date loginDate;
     
        @Future // 必须为一个未来的时间
        private Date expiryDate;
     
        。。。getter setter
    }

### 分组验证示例 ###

public interface ValidationService { // 缺省可按服务接口区分验证场景，如：@NotNull(groups = ValidationService.class)   
        @interface Save{} // 与方法同名接口，首字母大写，用于区分验证场景，如：@NotNull(groups = ValidationService.Save.class)，可选
        void save(ValidationParameter parameter);
        void update(ValidationParameter parameter);
    }

### 关联验证示例 ###

import javax.validation.GroupSequence;
     
    public interface ValidationService {   
        @GroupSequence(Update.class) // 同时验证Update组规则
        @interface Save{}
        void save(ValidationParameter parameter);
     
        @interface Update{} 
        void update(ValidationParameter parameter);
    }

### 参数验证示例 ###

import javax.validation.constraints.Min;
    import javax.validation.constraints.NotNull;
     
    public interface ValidationService {
        void save(@NotNull ValidationParameter parameter); // 验证参数不为空
        void delete(@Min(1) int id); // 直接对基本类型参数验证
    }

## 配置 ##

### 在客户端验证参数 ###

<dubbo:reference id="validationService" interface="org.apache.dubbo.examples.validation.api.ValidationService" validation="true" />

### 在服务器端验证参数 ###

<dubbo:service interface="org.apache.dubbo.examples.validation.api.ValidationService" ref="validationService" validation="true" />

## 验证异常信息 ##

import javax.validation.ConstraintViolationException;
    import javax.validation.ConstraintViolationException;
     
    import org.springframework.context.support.ClassPathXmlApplicationContext;
     
    import org.apache.dubbo.examples.validation.api.ValidationParameter;
    import org.apache.dubbo.examples.validation.api.ValidationService;
    import org.apache.dubbo.rpc.RpcException;
     
    public class ValidationConsumer {   
        public static void main(String[] args) throws Exception {
            String config = ValidationConsumer.class.getPackage().getName().replace('.', '/') + "/validation-consumer.xml";
            ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(config);
            context.start();
            ValidationService validationService = (ValidationService)context.getBean("validationService");
            // Error
            try {
                parameter = new ValidationParameter();
                validationService.save(parameter);
                System.out.println("Validation ERROR");
            } catch (RpcException e) { // 抛出的是RpcException
                ConstraintViolationException ve = (ConstraintViolationException) e.getCause(); // 里面嵌了一个ConstraintViolationException
                Set<ConstraintViolation<?>> violations = ve.getConstraintViolations(); // 可以拿到一个验证错误详细信息的集合
                System.out.println(violations);
            }
        } 
    }

--------------------

**备注**

1.  自 `2.1.0` 版本开始支持, 如何使用可以参考 [dubbo 项目中的示例代码][dubbo] [↩︎][Link 1]
2.  验证方式可扩展，扩展方式参见开发者手册中的[验证扩展][Link 2] [↩︎][Link 3]

[dubbo]: https://github.com/apache/dubbo-samples/tree/master/dubbo-samples-validation
[Link 1]: http://dubbo.apache.org/zh-cn/docs/user/demos/parameter-validation.html#fnref1
[Link 2]: http://dubbo.apache.org/zh-cn/docs/dev/impls/validation.html
[Link 3]: http://dubbo.apache.org/zh-cn/docs/user/demos/parameter-validation.html#fnref2