cloudevents 学习二 java 代码集成试用

主要是测试cloudevents 与java 的集成（client 使用nodejs）

nodejs client

const axios = require("axios").default;

const { emitterFor, Mode, HTTP,CloudEvent } = require("cloudevents");

 

const type = "userlogin"

const source = "itmd_cust"

const subject = "demo"

const datacontenttype = "application/json"

const data  = {

    name:"dalongdemo",

    age:333

}

const ce = new CloudEvent({ type, source, data:data ,datacontenttype,subject });

const message = HTTP.binary(ce); // Or HTTP.structured(ce)

console.log(message.headers)

function sendWithAxios2(message) {

    // Do what you need with the message headers

    // and body in this function, then send the

    // event

    axios({

        method: "post",

        url: "http://localhost:8080/echo2",

        data: message.body,

        headers: message.headers,

      });

 

  }

const emit2 = emitterFor(sendWithAxios2, { mode: Mode.BINARY });

emit2(ce);

java 集成

主要集成了spring jackson

• pom 文件

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <parent>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-parent</artifactId>

        <version>2.5.3</version>

        <relativePath/> <!-- lookup parent from repository -->

    </parent>

    <groupId>com.dalong</groupId>

    <artifactId>batchapp</artifactId>

    <version>0.0.1-SNAPSHOT</version>

    <name>batchapp</name>

    <description>mybatch app</description>

    <properties>

        <java.version>1.8</java.version>

    </properties>

    <dependencies>

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

        </dependency>

        <dependency>

            <groupId>com.h2database</groupId>

            <artifactId>h2</artifactId>

            <version>1.3.156</version>

        </dependency>

        <dependency>

            <groupId>io.cloudevents</groupId>

            <artifactId>cloudevents-json-jackson</artifactId>

            <version>2.2.0</version>

        </dependency>

        <dependency>

            <groupId>io.cloudevents</groupId>

            <artifactId>cloudevents-http-basic</artifactId>

            <version>2.2.0</version>

        </dependency>

        <dependency>

            <groupId>io.cloudevents</groupId>

            <artifactId>cloudevents-spring</artifactId>

            <version>2.2.0</version>

        </dependency>

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-test</artifactId>

            <scope>test</scope>

        </dependency>

    </dependencies>

 

    <build>

        <plugins>

            <plugin>

                <groupId>org.springframework.boot</groupId>

                <artifactId>spring-boot-maven-plugin</artifactId>

            </plugin>

        </plugins>

    </build>

 

</project>

• convert 配置
  CloudEventHandlerConfiguration

 

@Configuration

public class CloudEventHandlerConfiguration implements WebMvcConfigurer {

    @Override

    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {

        converters.add(0,new CloudEventHttpMessageConverter());

    }

}

• controller 定义

package com.dalong.batchapp;

 

import com.fasterxml.jackson.databind.ObjectMapper;

import io.cloudevents.CloudEvent;

import io.cloudevents.core.builder.CloudEventBuilder;

import io.cloudevents.core.data.PojoCloudEventData;

import io.cloudevents.jackson.PojoCloudEventDataMapper;

import io.cloudevents.spring.http.CloudEventHttpUtils;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.http.HttpHeaders;

import org.springframework.http.ResponseEntity;

import org.springframework.web.bind.annotation.PostMapping;

import org.springframework.web.bind.annotation.RequestBody;

import org.springframework.web.bind.annotation.RequestHeader;

import org.springframework.web.bind.annotation.RestController;

 

import java.net.URI;

import java.util.UUID;

 

import static io.cloudevents.core.CloudEventUtils.mapData;

 

@RestController

public class EventController {

    private static final  ObjectMapper objectMapper  = new ObjectMapper();

    @PostMapping("/echo2")

    public void ce(@RequestBody CloudEvent event) {

       //  此处集成jackson 以及cloudevent 数据格式，方便消息体处理

        CloudEvent event1 = CloudEventBuilder.from(event)

                .withId(UUID.randomUUID().toString())

                .withSource(URI.create("https://spring.io/foos"))

                .withType("io.spring.event.Foo")

                .withData(event.getData().toBytes())

                .build();

        PojoCloudEventData<MyUser> cloudEventData = mapData(

                event,

                PojoCloudEventDataMapper.from(objectMapper,MyUser.class)

        );

        MyUser user = cloudEventData.getValue();

        System.out.println(user.toString());

    }

    @PostMapping("/echo")

    public ResponseEntity<MyUser> echo(@RequestBody MyUser foo, @RequestHeader HttpHeaders headers) {

        CloudEvent attributes = CloudEventHttpUtils.fromHttp(headers)

                .withId(UUID.randomUUID().toString())

                .withSource(URI.create("https://spring.io/foos"))

                .withType("io.spring.event.Foo")

                .build();

        System.out.println(foo.toString());

        System.out.println(headers.toString());

        HttpHeaders outgoing = CloudEventHttpUtils.toHttp(attributes);

        return ResponseEntity.ok().headers(outgoing).body(foo);

    }

}

效果

• node client

• spring boot 消息

参考资料

https://stackoverflow.com/questions/3907929/should-i-declare-jacksons-objectmapper-as-a-static-field
https://cloudevents.github.io/sdk-java/json-jackson.html
https://cloudevents.io/
https://cloudevents.github.io/sdk-java/http-basic.html
https://cloudevents.github.io/sdk-java/spring.html