Http連接池PoolingHttpClientConnectionManager的應用

前言

Http連接需要的三次握手開銷很大, 傳統的HttpURLConnection並不支持連接池, HTTP1.1以上默認開啓keepalive, 對於現在springcloud橫行的社會, feign可以配置好http連接池, 不過總會有某些個別的接口不在服務中, 還有一些非springboot的老舊項目也要加入cloud大家族中, 對於內部頻繁訪問的url地址, 這就需要一款量身定做的工具類了.

講解

先來看看測試效果, 兩種工具類的時間消耗對比.

這個是測試用的方法, 前後分別調用了某一接口100次, 進行時間統計, 系統頁面按F12能看到平均握手速度大概是3ms

long start = System.currentTimeMillis();
for (int i = 0; i < 100; i++) {
    result = commonManager.getPolicyGoNew(inputStr);
}
long end = System.currentTimeMillis();
System.out.println(String.valueOf(end - start));

System.out.println("***********");

long start2 = System.currentTimeMillis();
for (int i = 0; i < 100; i++) {
    result = commonManager.getPolicyGo(inputStr);
}
long end2 = System.currentTimeMillis();
System.out.println(String.valueOf(end2 - start2));

100次快了647ms, 平均一次6ms, 握三次手大概要這麼久吧

9612
***********
10259

第二次我調換了順序, 500.for, 500次快了2341ms, 平均一次4.6ms, 更接近3ms了

50906
***********
48565
52327
***********
47021

錯誤的請求數據, 可以立馬返回數據, 更能說明是否節省了握手時間

9625
***********
8868
9251
***********
8718

不過我之前都是調用的生產環境的接口, 效率還是比較高的, 下面我在uat環境測試一下

正常查詢詳情數據消耗時間

500次快了4900ms, 平均一次10ms

72712
***********
67839

錯誤的請求數據, 可以立馬返回數據, 更能說明是否節省了握手時間

500次快了2400ms, 平均一次4.8ms

6439
***********
4063

代碼

原httputil, 看實現部分就好

import org.apache.http.HttpStatus;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.utils.HttpClientUtils;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;

import java.util.Map;

public class HttpUtils {

	public interface ResponseCallback {
		void onResponse(CloseableHttpResponse response) throws Exception;
		void onError(int resultCode, String resultStr) throws Exception;
	}

    public static void headerPost(String urlStr, String data, ResponseCallback callback, Map<String, String> headerMap) throws Exception {
		doPost(urlStr, data, callback, headerMap, 300000);
    }

    private static void doPost(String urlStr, String data, ResponseCallback callback, Map<String, String> headerMap, int timeOut) throws Exception {
        HttpUriRequest request = null;
        CloseableHttpClient client = null;
        CloseableHttpResponse response = null;
        try {
			request = new HttpPost(urlStr);
			if (headerMap != null) {
				for(Map.Entry<String, String> entry : headerMap.entrySet()){
					request.setHeader(entry.getKey(), entry.getValue());
				}
			}
			if (null != data && !"".equals(data)) {
				((HttpPost) request).setEntity(new ByteArrayEntity(data.getBytes("utf-8")));
			}
            RequestConfig config = RequestConfig.custom().setConnectionRequestTimeout(timeOut).setConnectTimeout(timeOut).setSocketTimeout(timeOut).build();
            client = HttpClientBuilder.create().setDefaultRequestConfig(config).build();
            response = client.execute(request);
            int resultCode = response.getStatusLine().getStatusCode();
            if (resultCode == HttpStatus.SC_OK) {
            	callback.onResponse(response);
            } else {
                throw new Exception(resultCode + ":system error");
            }
        } catch (Exception e) {
        	callback.onError(HttpStatus.SC_INTERNAL_SERVER_ERROR, e.toString());
        } finally {
            if (request != null && !request.isAborted()) {
                request.abort();
                request = null;
            }
            if (client != null) {
                HttpClientUtils.closeQuietly(client);
                client = null;
            }
            if (response != null) {
                HttpClientUtils.closeQuietly(response);
                response = null;
            }
        }
    }
}

帶連接池的httputil, 初版支持一個url連接, 可更改爲Map維護

import org.apache.http.*;
import org.apache.http.client.HttpRequestRetryHandler;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpRequestBase;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.config.Registry;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.conn.ConnectTimeoutException;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.socket.LayeredConnectionSocketFactory;
import org.apache.http.conn.socket.PlainConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.protocol.HttpContext;
import org.apache.http.util.EntityUtils;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLHandshakeException;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.net.UnknownHostException;
import java.util.Map;

public class HttpClientUtil {

    static final int timeOut = 10 * 1000;

    private static CloseableHttpClient httpClient = null;

    private final static Object syncLock = new Object();

    private static void config(HttpRequestBase httpRequestBase) {
        // 配置請求的超時設置
        RequestConfig requestConfig = RequestConfig.custom()
                .setConnectionRequestTimeout(timeOut)
                .setConnectTimeout(timeOut).setSocketTimeout(timeOut).build();
        httpRequestBase.setConfig(requestConfig);
    }

    /**
     * 獲取HttpClient對象
     */
    public static CloseableHttpClient getHttpClient(String url) {
        String hostname = url.split("/")[2];
        int port = 80;
        if (hostname.contains(":")) {
            String[] arr = hostname.split(":");
            hostname = arr[0];
            port = Integer.parseInt(arr[1]);
        }
        if (httpClient == null) {
            synchronized (syncLock) {
                if (httpClient == null) {
                    httpClient = createHttpClient(200, 40, 100, hostname, port);
                }
            }
        }
        return httpClient;
    }

    public static CloseableHttpClient createHttpClient(int maxTotal, int maxPerRoute, int maxRoute, String hostname, int port) {
        ConnectionSocketFactory plainsf = PlainConnectionSocketFactory.getSocketFactory();
        LayeredConnectionSocketFactory sslsf = SSLConnectionSocketFactory.getSocketFactory();
        Registry<ConnectionSocketFactory> registry = RegistryBuilder
                .<ConnectionSocketFactory> create().register("http", plainsf).register("https", sslsf).build();
        PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager(registry);
        // 將最大連接數增加
        cm.setMaxTotal(maxTotal);
        // 將每個路由基礎的連接增加
        cm.setDefaultMaxPerRoute(maxPerRoute);
        HttpHost httpHost = new HttpHost(hostname, port);
        // 將目標主機的最大連接數增加
        cm.setMaxPerRoute(new HttpRoute(httpHost), maxRoute);

        // 請求重試處理
        HttpRequestRetryHandler httpRequestRetryHandler = new HttpRequestRetryHandler() {
            public boolean retryRequest(IOException exception, int executionCount, HttpContext context) {
                if (executionCount >= 5) {// 如果已經重試了5次，就放棄
                    return false;
                }
                if (exception instanceof NoHttpResponseException) {// 如果服務器丟掉了連接，那麼就重試
                    return true;
                }
                if (exception instanceof SSLHandshakeException) {// 不要重試SSL握手異常
                    return false;
                }
                if (exception instanceof InterruptedIOException) {// 超時
                    return false;
                }
                if (exception instanceof UnknownHostException) {// 目標服務器不可達
                    return false;
                }
                if (exception instanceof ConnectTimeoutException) {// 連接被拒絕
                    return false;
                }
                if (exception instanceof SSLException) {// SSL握手異常
                    return false;
                }

                HttpClientContext clientContext = HttpClientContext.adapt(context);
                HttpRequest request = clientContext.getRequest();
                // 如果請求是冪等的，就再次嘗試
                if (!(request instanceof HttpEntityEnclosingRequest)) {
                    return true;
                }
                return false;
            }
        };

        CloseableHttpClient httpClient = HttpClients.custom()
                .setConnectionManager(cm)
                .setRetryHandler(httpRequestRetryHandler).build();

        return httpClient;
    }

    public static String post(String url, String data, Map<String, String> headerMap) throws IOException {
        HttpPost httppost = new HttpPost(url);
        config(httppost);
        if (headerMap != null) {
            for(Map.Entry<String, String> entry : headerMap.entrySet()){
                httppost.setHeader(entry.getKey(), entry.getValue());
            }
        }
        if (null != data && !"".equals(data)) {
            httppost.setEntity(new ByteArrayEntity(data.getBytes("utf-8")));
        }
        CloseableHttpResponse response = null;
        try {
            response = getHttpClient(url).execute(httppost, HttpClientContext.create());
            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "utf-8");
            //EntityUtils.consume(entity);
            return result;
        } catch (Exception e) {
            throw e;
        } finally {
            try {
                if (response != null)
                    response.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static String get(String url) {
        HttpGet httpget = new HttpGet(url);
        config(httpget);
        CloseableHttpResponse response = null;
        try {
            response = getHttpClient(url).execute(httpget,
                    HttpClientContext.create());
            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "utf-8");
            EntityUtils.consume(entity);
            return result;
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (response != null)
                    response.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return null;
    }
}

總結

不管怎麼來回測試, 都有時間上的差別, 連接池明顯要快一些, 而且對服務器的資源消耗也小, 對接口提供者也比較友好, 當然這一切有個前提, 就是雙方都是http1.1以上, 默認開啓keepAlive, 畢竟http2.0協議還沒有太普及.