REST web服务已成为在web上应用程序集成的首选方式。在其核心中，REST定义了系统由客户端交互的资源组成。这些资源以超媒体驱动的方式实现。Spring MVC为构建这些服务提供了坚实的基础。但是，对于多域对象系统，即使实施REST web服务的最简单原则也可能相当乏味，并且导致大量样板代码。

Spring Data REST构建在Spring Data repositories之上，并自动将其导出为REST资源。它利用超媒体来允许客户端查找存储库暴露的功能，并将这些资源自动集成到相关的超媒体功能中。

• 根据model，生成HAL风格的restful API
• 根据model，维护实体之间的关系
• 支持分页
• 允许动态地过滤集合资源
• 允许通过处理Spring ApplicationEvents处理REST请求。
• 目前支持JPA，MongoDB，Neo4j，Solr，Cassandra，Gemfire。
• 支持自定义

将Spring Data REST添加到Spring Boot项目

dependencies {
    ...
    compile "org.springframework.boot:spring-boot-starter-data-rest:$spring_boot_version"
    ...
}

完整的build.gradle文件

group 'name.quanke.kotlin'
version '1.0-SNAPSHOT'

buildscript {
    ext.kotlin_version = '1.2.10'
    ext.spring_boot_version = '1.5.4.RELEASE'
    ext.springfox_swagger2_version = '2.7.0'
    ext.mysql_version = '5.1.21'
    ext.mybatis_version = '1.1.1'
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath("org.springframework.boot:spring-boot-gradle-plugin:$spring_boot_version")

//        Kotlin整合SpringBoot的默认无参构造函数，默认把所有的类设置open类插件
        classpath("org.jetbrains.kotlin:kotlin-noarg:$kotlin_version")
        classpath("org.jetbrains.kotlin:kotlin-allopen:$kotlin_version")
    }
}

apply plugin: 'kotlin'
apply plugin: "kotlin-spring" // See https://kotlinlang.org/docs/reference/compiler-plugins.html#kotlin-spring-compiler-plugin
apply plugin: 'org.springframework.boot'
apply plugin: "kotlin-jpa"  //https://stackoverflow.com/questions/32038177/kotlin-with-jpa-default-constructor-hell
jar {
    baseName = 'chapter11-6-7-service'
    version = '0.1.0'
}
repositories {
    mavenCentral()
}


dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-jre8:$kotlin_version"
    compile("org.jetbrains.kotlin:kotlin-reflect:${kotlin_version}")

    compile "org.springframework.boot:spring-boot-starter-data-jpa:$spring_boot_version"
    compile "org.springframework.boot:spring-boot-starter-data-rest:$spring_boot_version"
    compile "mysql:mysql-connector-java:$mysql_version"


    testCompile "org.springframework.boot:spring-boot-starter-test:$spring_boot_version"
    testCompile "org.jetbrains.kotlin:kotlin-test-junit:$kotlin_version"

}

compileKotlin {
    kotlinOptions.jvmTarget = "1.8"
}
compileTestKotlin {
    kotlinOptions.jvmTarget = "1.8"
}

创建对象User

import javax.persistence.*

/**
 * Created by http://quanke.name on 2018/1/10.
 */

@Entity
data class User(
        @Id
        @GeneratedValue(strategy = GenerationType.AUTO)
        var id: Long = -1,
        @Column(nullable = false)
        var username: String = "",

        var password: String = ""


)

创建UserRepository

• 增加@RepositoryRestResource注解 关于@RepositoryRestResource详细的使用介绍，请参考： https://springcloud.cc/spring-data-rest-zhcn.html

import name.quanke.kotlin.chaper11_6_7.entity.User
import org.springframework.data.jpa.repository.JpaRepository
import org.springframework.data.jpa.repository.Query
import org.springframework.data.repository.query.Param
import org.springframework.data.rest.core.annotation.RepositoryRestResource

@RepositoryRestResource(path="user")
interface UserRepository : JpaRepository<User, Long> {

    fun findByUsername(username: String): List<User>

    fun findByUsernameAndPassword(username: String, password: String?): User

    @Query("from User u where u.username=:username")
    fun findUser(@Param("username") username: String): User

}

配置

在application.yml文件中增加

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/test
    username: root
    password: 123456
    driver-class-name: com.mysql.jdbc.Driver

启动

import org.springframework.boot.SpringApplication
import org.springframework.boot.autoconfigure.SpringBootApplication


/**
 * Created by http://quanke.name on 2018/1/9.
 */

//参考：http://blog.csdn.net/soul_code/article/details/54108105

@SpringBootApplication
class Application

fun main(args: Array<String>) {
    SpringApplication.run(Application::class.java, *args)
}

测试

访问 127.0.0.1:8080/user

返回：

{
    "_embedded": {
        "users": [
            {
                "username": "http://gof.quanke.name",
                "password": "1111",
                "_links": {
                    "self": {
                        "href": "http://127.0.0.1:8083/user/73"
                    },
                    "user": {
                        "href": "http://127.0.0.1:8083/user/73"
                    }
                }
            },
            {
                "username": "java.quanke.name",
                "password": "12",
                "_links": {
                    "self": {
                        "href": "http://127.0.0.1:8083/user/74"
                    },
                    "user": {
                        "href": "http://127.0.0.1:8083/user/74"
                    }
                }
            },
            {
                "username": "test.quanke.name",
                "password": "aa",
                "_links": {
                    "self": {
                        "href": "http://127.0.0.1:8083/user/75"
                    },
                    "user": {
                        "href": "http://127.0.0.1:8083/user/75"
                    }
                }
            },
            {
                "username": "es.quanke.name",
                "password": "12",
                "_links": {
                    "self": {
                        "href": "http://127.0.0.1:8083/user/76"
                    },
                    "user": {
                        "href": "http://127.0.0.1:8083/user/76"
                    }
                }
            },
            {
                "username": "as.quanke.name",
                "password": "12",
                "_links": {
                    "self": {
                        "href": "http://127.0.0.1:8083/user/77"
                    },
                    "user": {
                        "href": "http://127.0.0.1:8083/user/77"
                    }
                }
            },
            {
                "username": "vertx.quanke.name",
                "password": "12",
                "_links": {
                    "self": {
                        "href": "http://127.0.0.1:8083/user/78"
                    },
                    "user": {
                        "href": "http://127.0.0.1:8083/user/78"
                    }
                }
            }
        ]
    },
    "_links": {
        "self": {
            "href": "http://127.0.0.1:8083/user{?page,size,sort}",
            "templated": true
        },
        "profile": {
            "href": "http://127.0.0.1:8083/profile/user"
        },
        "search": {
            "href": "http://127.0.0.1:8083/user/search"
        }
    },
    "page": {
        "size": 20,
        "totalElements": 6,
        "totalPages": 1,
        "number": 0
    }
}

访问 127.0.0.1:8083/user/73

注意： 73 是user id 根据自己的实际情况测试

返回：

{
    "username": "http://gof.quanke.name",
    "password": "1111",
    "_links": {
        "self": {
            "href": "http://127.0.0.1:8083/user/73"
        },
        "user": {
            "href": "http://127.0.0.1:8083/user/73"
        }
    }
}

Spring Data REST 能做的事情很多，这篇文章先介绍到这里，先在这里埋个坑，之后会出更加详细的文章说Spring Data REST。

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参考

• https://springcloud.cc/spring-data-rest-zhcn.html
• https://www.jianshu.com/p/84f2bbffb885
• https://www.cnblogs.com/aguncn/p/6762392.html
• http://blog.csdn.net/soul_code/article/details/54108105
• https://github.com/spring-projects/spring-data-examples/tree/master/rest