ESA RestClient

ESA RestClient is an asynchronous event-driven http client based on netty.

Features

• Http1/H2/H2cUpgrade
• Https
• Epoll/NIO
• Serialize and Deserialize
• Interceptor
• Filter
• Retry, Redirect, 100-expect-continue
• Segmented read/write
• Multipart
• Metrics
• more features...

Maven Dependency

Note：netty 4.1.52.Final and tcnative 2.0.34.Final are directly dependent on.

Note: Please make sure the version of tcnative matches the version of netty.

<dependency>
    <groupId>io.esastack</groupId>
    <artifactId>restclient</artifactId>
    <version>${esa-restclient.version}</version>
</dependency>

Quick Start

final RestClient client = RestClient.ofDefault();

final String entity = client.post("http://127.0.0.1:8081/")
                        .maxRetries(3)     //设置重试次数
                        .readTimeout(3000)      //读超时
                        .entity("Hello Server")
                        .execute()
                        .toCompletableFuture()
                        .get()
                        .bodyToEntity(String.class);

Performance

Test cases

• We built an echo server by ESA-HTTPServer and used ESA-RestClient(1.0.0)、ESA-HttpClient(1.0.0) to do the requests for RPS testing with fixed string:'OK' and different ratio of asynchronous to synchronous requests.This is because if all requests are executed asynchronously, many requests are requesting to obtain connections, resulting in errors. Therefore, the test method is to use asynchronous and synchronous alternately to make requests, so as to achieve the best performance.
• Also we used Apache HttpComponents(5.1.2) and OK-HttpClient(4.9.2) to build a client which is same with above for RPS testing.

Hardware Used

We used the following software for the testing:

	OS	CPU	Mem(G)
client	CentOS Linux release 7.6.1810(docker)	4	8
server	CentOS Linux release 7.6.1810(docker)	8	16

JVM Options

-Xms1024m -Xmx1024m -XX:MetaspaceSize=128m -XX:MaxMetaspaceSize=256m -XX:+UseConcMarkSweepGC -XX:+UseCMSInitiatingOccupancyOnly -XX:CMSInitiatingOccupancyFraction=70

Ping Result

Client Options

Framework	Options
ESA-HttpClient	System.setProperty("io.esastack.httpclient.ioThreads", "4"); HttpClient.create()   .connectTimeout(1000)   .readTimeout(3000)   .connectionPoolSize(connectionPoolSize)   .connectionPoolWaitingQueueLength(512).build();
ESA-RestClient	System.setProperty("io.esastack.httpclient.ioThreads", "4"); RestClient.create()   .connectTimeout(1000)   .readTimeout(3000)   .connectionPoolSize(connectionPoolSize)   .connectionPoolWaitingQueueLength(512).build();
Apache HttpComponents	PoolingAsyncClientConnectionManager connectionManager = PoolingAsyncClientConnectionManagerBuilder.create()   .setMaxConnTotal(connectionPoolSize)   .setConnectionTimeToLive(TimeValue.ofMinutes(1L))   .build(); IOReactorConfig ioReactorConfig =IOReactorConfig.custom()   .setIoThreadCount(4)   .build(); client = HttpAsyncClients.custom()   .setConnectionManager(connectionManager)   .setIOReactorConfig(ioReactorConfig)   .setDefaultRequestConfig(RequestConfig.custom()     .setConnectTimeout(Timeout.ofSeconds(1))     .setResponseTimeout(Timeout.ofSeconds(3))     .build())   .build();
OK-HttpClient	client = new OkHttpClient.Builder()   .connectTimeout(1, TimeUnit.SECONDS)   .readTimeout(3, TimeUnit.SECONDS)   .build(); client.dispatcher().setMaxRequests(maxRequest); client.dispatcher().setMaxRequestsPerHost(maxRequest);

Best RPS

	ESA-HttpClient	ESA-RestClient	Apache HttpComponents	OK-HttpClient
Best RPS	116013.75	111217.98	89633.73	70501.59
ratio of async to sync	800	800	50	300
num of io threads	4	4	4	10(MaxRequestsPerHost)
num of biz threads	1	1	10	1

See more details in Reference Doc