GraphQL DGS 框架

netflix 已开放其 Domain Graph Service（DGS）框架的源代码 ，该框架是为了方便整合 GraphQL 使用，用于简化 GraphQL 的实现。

图片

GraphQL 主要是作用于数据接口，比如前端后端交互。无需定义或修改后台 Controller、Service 等业务代码即可实现灵活的数据变更，客户端可以自由获取服务端事先定义好的数据，提高了交互接口的灵活性

组件依赖

graphql-dgs-spring-boot-starter

com.netflix.graphql.dgs

3.5.1

DGS 必须从 jcenter 下载,不然部分依赖无法下载。踩坑很久

true

false

central

bintray

https://jcenter.bintray.com

bintray-plugins

定义接口 schema

/src/main/resources/schema/schema.graphqls

此文件定义了客户端请求入参格式和查询数据类型

type Query {

shows(title: String ,releaseYear: Int): [Show]

}

type Show {

title: String

releaseYear: Int

定义数据抽取规则

@DgsComponent

public class ShowsDatafetcher {

@DgsData(parentType = “Query”, field = “shows”)

public List shows(@InputArgument(“title”) String title, @InputArgument(“releaseYear”) Integer releaseYear) {

if (title == null) {

return shows;

return shows.stream().filter(s -> s.getTitle().contains(title)).collect(Collectors.toList());

private final List shows = List.of(

new Show(“java”, 1995),

new Show(“php”, 1995),

new Show(“python”, 1990),

new Show(“golang”, 2009),

new Show(“rust”, 2015)

);

UI 前端调试

访问: http://localhost:8080/graphiql

条件查询

接口调用

curl --location --request POST ‘http://localhost:8080/graphql’

–header ‘Content-Type: application/json’

–data-raw ‘{“query”:"{\n shows(title: “java”, releaseYear: 1995) {\n title\n releaseYear\n }\n}\n",“variables”:null}’

java 调用

@SpringBootTest(classes = {DgsAutoConfiguration.class, ShowsDatafetcher.class})

class ShowsDatafetcherTests {

@Autowired

DgsQueryExecutor dgsQueryExecutor;

@Test

void shows() {

List titles = dgsQueryExecutor.executeAndExtractJsonPath(

" { shows { title releaseYear }}",

“data.shows[*].title”);

assertThat(titles).contains(“java”);

本节源码

源码: https://github.com/lltx/dgs-demo

DGS 官网: https://netflix.github.io/dgs