Spring Boot与Kotlin使用Spring Data Rest创建HAL风格Restful接口

摘要: 《Spring Boot 与 kotlin 实战》之使用Spring Data Rest创建HAL风格Restful接口

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