spring-integration连接http spring调用http接口

在一些简单的应用中，可以用spring-integration来获取http请求内容，从而实现简单的http接口调用，相对于HttpClient要更简单一些，个人理解可以在一些简单的场景下使用，首先需要引入spring-integration-http

<dependency>
   <groupId>org.springframework.integration</groupId>
   <artifactId>spring-integration-http</artifactId>
   <version>5.3.1.RELEASE</version>
</dependency>

http的配置与其它的spring-integration配置有所区别，这里的入站管道实际上是http请求外网服务器，这里会立即返回数据，而不是像tcp或mqtt那样异步调用数据处理接口，配置如下：

package org.noka.serialservice.config;
 
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpMethod;
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.integration.config.EnableIntegration;
import org.springframework.integration.http.outbound.AbstractHttpRequestExecutingMessageHandler;
import org.springframework.integration.http.outbound.HttpRequestExecutingMessageHandler;
import org.springframework.integration.http.support.DefaultHttpHeaderMapper;
import org.springframework.messaging.MessageHandler;
 
/** ----------------------------------------------
 * http请求配置
 * @author xiefangjian@163.com
 * @version 1.0.0
 ** -------------------------------------------**/
@EnableIntegration
@Configuration
public class HttpConfig {
 
    private String url="http://192.168.50.46:8088/";//http服务器地址
    /**
     * http请求配置
     * 这量数据管道名称为 http_out
     * @return
     */
    @Bean
    @ServiceActivator(inputChannel = "http_out")
    public MessageHandler httpHandler(){
        AbstractHttpRequestExecutingMessageHandler http = new HttpRequestExecutingMessageHandler(url);
        DefaultHttpHeaderMapper httpHeaderMapper= new DefaultHttpHeaderMapper();
        httpHeaderMapper.setOutboundHeaderNames("*");//允许自定义协议的头部信息
        http.setHttpMethod(HttpMethod.POST);//post方式
        http.setCharset("UTF-8");//编码方式
        http.setHeaderMapper(httpHeaderMapper);
        http.setExpectedResponseType(String.class);//请求以纯字符串的方式返回
        return http;
    }
}

需要请求一个http服务时，同样是通过一个接口来完成，这个接口实现方式如下：

package org.noka.serialservice.service;
 
import org.springframework.integration.annotation.Gateway;
import org.springframework.integration.annotation.MessagingGateway;
import org.springframework.messaging.Message;
import org.springframework.stereotype.Component;
import java.util.Map;
/**----------------------------------------------------------------
 * 发送消息网关,其它需要发向服务器发送消息时，调用该接口
 * @author  xiefangjian@163.com
 * @version  1.0.0
 **--------------------------------------------------------------**/
@MessagingGateway
@Component
public interface MsgGateway {
    
    /**
     * http请求接口
     * @param out 需要发送的内容
     * @return
     */
    @Gateway(requestChannel = "http_out")
    String Post(Message<Map<String,String>> out);
}

后面在任何地方都可以使用MsgGateway接口来请求服务器的内容，像下面这样

//-----需要传到服务器上的参数----------------------------------------
Map<String,String> pars = new HashMap<>();
pars.put("par1","xiefangjian");//参数1
Message<Map<String,String>> ms = MessageBuilder.withPayload(pars)
     .setHeader(HttpHeaders.ACCEPT_LANGUAGE,"zh-CN")//Accept-Language 设置为zh-CN
     .setHeader("aaaa","xiefangjian")//自定义协议头
     .build();
String body = msgGateway.Post(ms);//这里body为服务器返回的内容