JarCasting 
通过GraphQL Schema描述业务领域，并提供一套基于GraphQL+Dgraph的开发框架，快速落地DDD。
注: 基于 SpringBoot 2.x
Module
- core: 通用代码
- dgraph: 封装 Dgraph 数据库操作
- graphql: 为 Spring 项目封装 Graphql 接口
- graphql-client: 提供调用Graphql Server Api 的能力，只依赖spring web 可独立使用
- mq: 简易内嵌消息队列
- generator: 代码生成器。根据GraphQL Schema生成Java代码及DgraphSchema
如何使用
可根据需求单独使用各组件. 配置文件，可以参考 full-sample#application-default.properties
通用配置
# 开启zipkin监控，默认开启
spring.zipkin.enabled=true
# 设置zipkin上报地址
spring.zipkin.base-url=http://localhost:9411
1. 提供Graphql接口
1.1 添加依赖
<dependency>
<groupId>com.github.yituhealthcare</groupId>
<artifactId>arc-graphql</artifactId>
<version>1.5.0</version>
</dependency>
1.2 创建schema. 默认路径为 resources:graphql/schema.graphqls 可以通过配置文件修改
schema{
query: Query,
mutation: Mutation
}
type Query{
projects(name: String): [Project]
}
type Mutation{
createProject(payload: ProjectInput): Project
}
type Project{
id: String!
name: String!
description: String!
createTime: DateTime!
}
input ProjectInput{
name: String!
description: String!
}
1.3 编写java代码
如果有 Consumer 订阅，graphql调用之后会发送对应的领域事件给 Consumer 进行消费
服务启动后可以
- 访问 http://localhost:${port}/playground 进行方法调用
- 访问 http://localhost:${port}/voyager 查询领域关系
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
@GraphqlQuery
public DataFetcher<List<Project>> projects() {
return dataFetchingEnvironment -> {
String name = dataFetchingEnvironment.getArgument("name")
return Arrays.asList(new Project());
};
}
@GraphqlMutation
public DataFetcher<Project> createProject() {
return dataFetchingEnvironment -> {
ProjectInput input = GraphqlPayloadUtil.resolveArguments(dataFetchingEnvironment.getArguments(), ProjectInput.class);
OffsetDateTime now = OffsetDateTime.now();
Project project = new Project();
return project;
};
}
@Consumer(topic = "projects")
public void listener(Message<DomainEvent> record){}
static class Project {
public String id;
public String name;
public String description;
public OffsetDateTime createTime;
}
static class ProjectInput {
private String name;
private String description;
}
}
2. 调用dgraph数据库
可以通过docker命令在本地启动dgraph数据库
docker run --rm -it -p 8080:8080 -p 9080:9080 -p 8000:8000 -v ~/dgraph:/dgraph dgraph/standalone:v20.03.0
2.1 添加依赖
<dependency>
<groupId>com.github.yituhealthcare</groupId>
<artifactId>arc-dgraph</artifactId>
<version>1.5.0</version>
</dependency>
2.2 配置文件
# 配置dgraph数据库地址
arc.dgraph.urls=localhost:9080
2.3 编写查询语句和java代码
SimpleDgraphRepository 提供了 save() 、 getOne() 等常用方法，如果要进行复杂操作需要另外编写操作语句
查询语句
<dgraph>
<var id="type">
PROJECT
</var>
<var id="common">
uid
expand(PROJECT)
</var>
<query id="listByProjectId">
query listByName($name: string) {
listByName(func: eq(name, $name)) {
$common
}
}
</query>
<mutation id="updateName">
<![CDATA[
<$id> <PROJECT.name> "$name" .
]]>
</mutation>
</dgraph>
java代码
@Repository
public class ProjectRepository extends SimpleDgraphRepository<Project> {
public List<Project> listByName(String name) {
Map<String, String> vars = new HashMap<>();
vars.put("name", name);
return this.queryForList("project.listByName", vars);
}
public void updateName(String name) {
Map<String, String> vars = new HashMap<>();
vars.put("name", name);
this.mutation("project.updateName", vars);
}
}
3. 通过graphql-client调用graphql服务
3.1 添加依赖
<dependency>
<groupId>com.github.yituhealthcare</groupId>
<artifactId>arc-graphql-client</artifactId>
<version>1.5.0</version>
</dependency>
3.2 编写调用语句
新建文件 resources:ql/echo.graphql
query hello($echoText: String!) {
echo(text:$echoText)
}
3.3 编写java代码
@EnableGraphqlClients(basePackages = "com.github.yituhealthcare.arcgraphqlclientsample")
@RestController
@SpringBootApplication
public class ArcGraphqlClientSampleApplication {
public static void main(String[] args) {
SpringApplication.run(ArcGraphqlClientSampleApplication.class, args);
}
@Autowired
private GitlabGraphqlClient gitlabGraphqlClient;
@RequestMapping("rest")
public String rest(@RequestParam(required = false, defaultValue = "Arc") String name) {
return gitlabGraphqlClient.echo("Hello " + name).getData();
}
@GraphqlClient(value = "gitlabGraphqlClient", url = "https://gitlab.com/api/graphql")
interface GitlabGraphqlClient {
@GraphqlMapping(path = "ql/echo.graphql")
GraphqlResponse<String> echo(@GraphqlParam("echoText") String text);
}
}
4. 通过Generator生成代码
4.1 依赖中添加Maven插件
<build>
<plugins>
<plugin>
<groupId>com.github.yituhealthcare</groupId>
<artifactId>arc-maven-plugin</artifactId>
<version>1.5.0</version>
</plugin>
</plugins>
</build>
4.2 新建配置文件， 默认路径为 resources:arc-generator.json 可以通过plugin配置修改
{
"basePackage": "com.github.yituhealthcare.arcgeneratorsample",
"dropAll": false,
"genStrategies": [
{
"codeGenOperation": "SKIP",
"codeGenType": "REPO"
},
{
"codeGenOperation": "OVERRIDE",
"codeGenType": "API"
}
],
"ignoreJavaFileNames": [
"User"
],
"dgraphPath": "dgraph/schema.dgraph"
}
4.3 执行maven命令
mvn arc:generate
Manual
Sample
背景知识
示例
整体开发流程
- 定义GraphQL schema，产生GraphQL.schema文件
- 定义dgraph schema，修改类型并定义type。
- 创建javaBean并指定@DgraphType、@UidField、@RelationshipField
- 创建 SimpleDgraphRepository 的子类声明为@Repository
- 创建 @Graphql类及@GraphQLQuery、@GraphQLMutation 方法
- 通过 http://localhost:${port}/playground 直接create方法
- 编写xxDgraph.xml实现query方法
Support
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