# spring-cloud-openfeign-async 

**Repository Path**: RemoteControl/spring-cloud-openfeign

## Basic Information

- **Project Name**: spring-cloud-openfeign-async 
- **Description**: spring-cloud-openfeign-async 支持hc5异步通讯
- **Primary Language**: Java
- **License**: Apache-2.0
- **Default Branch**: 3.1.x
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 4
- **Forks**: 2
- **Created**: 2023-05-19
- **Last Updated**: 2024-03-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

////
DO NOT EDIT THIS FILE. IT WAS GENERATED.
Manual changes to this file will be lost when it is generated again.
Edit the files in the src/main/asciidoc/ directory instead.
////


image::https://github.com/spring-cloud/spring-cloud-openfeign/workflows/Build/badge.svg?branch=main&style=svg["Build",link="https://github.com/spring-cloud/spring-cloud-openfeign/actions"]



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== 异步模块

=== 3.0/3.1版添加模块 spring-cloud-openfeign-core-asyn 以支持异步，3.0/3.1版本openfeign支持异步
=== 使用方法：
	-  pom.xml引入（务必在spring-cloud-starter-openfeign之前）：
[source,xml]
----
	<dependency>
    			<groupId>org.springframework.cloud</groupId>
    			<artifactId>spring-cloud-openfeign-core-asyn</artifactId>
    			<version>3.0.8-SNAPSHOT</version>
    			<scope>compile</scope>
    		</dependency>
    		<!-- 以及真异步通讯模块 -->
    		<dependency>
            	<groupId>io.github.openfeign</groupId>
            	<artifactId>feign-hc5</artifactId>
            </dependency>
----
	- 注解：@EnableFeignClientsWithAsync() 启动openfeign
	- 配置添加（3.1版本不要配置 httpclient.hc5、okhttp、httpclient，否则可能启动失败）：
----
	feign:
      client:
        #启动异步（默认是同步的）
        asyn-enabled: true
      httpclient:
        hc5-async:
          #启用hc5的真异步通讯（默认是基于线程的伪异步）
          enabled: true
----
	- 具体接口添加<CompletableFuture>即可,如下，如果是同步的一样可以用，只是纯同步
----
        @RequestMapping(value ="/system/sysParam/paramValueAndDelaySecond/{paramName}", method = RequestMethod.GET)
       	CompletableFuture<Result<String>> paramValueAndDelaySecondAsyn(@PathVariable("paramName") String paramName, @RequestParam("seconds") Integer seconds);
----
===  已支持http2 性能应该能更上一层楼（异步长连接）
- 自建添加http2 client：
----
	@Bean
	public CloseableHttpAsyncClient httpAsyncClient5http2(FeignHttpClientProperties httpClientProperties) {
		log.info("CloseableHttpAsyncClient http2 1.0!");
		IOReactorConfig ioReactorConfig = IOReactorConfig.custom().setSoTimeout(Timeout.ofMilliseconds(250)) // 1.1
				.setSelectInterval(TimeValue.ofMilliseconds(50)) // 1.2
				.setSoTimeout(Timeout.of(httpClientProperties.getHc5().getSocketTimeout(),
						httpClientProperties.getHc5().getSocketTimeoutUnit()))
				.build();

		httpAsyncClient5 = HttpAsyncClients.customHttp2()
				.disableCookieManagement()
				.disableAutomaticRetries()
				.useSystemProperties()
				.setIOReactorConfig(ioReactorConfig)
				.setDefaultRequestConfig(RequestConfig.custom()
						.setRedirectsEnabled(httpClientProperties.isFollowRedirects())
						.setConnectTimeout(100, TimeUnit.MILLISECONDS)
						.build())
				.build();

		httpAsyncClient5.start();

		return httpAsyncClient5;
	}
----
- 后期通过属性支持支持http2


=== 以及准备把异步模块完全抽离成独立项目

=== 打包：mvn clean install -Dpmd.skip=true -Dcheckstyle.skip=true

=== 注意事项

-  异步导致的结果是发送也是异步（接口返回其实请求还未发送完）
-  RequestConfig 中 connectionRequestTimeout，影响异步发送超时（目前设置在connectTimeout，即设置ConnectTimeout即可）
-  影响并发的吞吐量的maxConnPerRoute,maxConnTotal(http1),当设置为1的场景下，基本上就是一条条的发送接受（实际感受到的瞬发，但是结果是依次累加实际返回）
-  http2吞吐量不受maxConnPerRoute,maxConnTotal影响，但是使劲发可能会存在上游拥堵

=== spring-cloud-openfeign 其他模块以、功能、描述见:
https://github.com/spring-cloud/spring-cloud-openfeign[Spring Cloud Openfeign]