HTTP连接如何保持登录状态？OkHttp或者HttpClient

上节我们讲过HTTP客户端，基于它们的优劣势，一般使用OkHttp或者HttpClient。所以这节我们主要针对这两个HTTP客户端实现登录一直保持功能。

OkHttp

设置cookie请求消息头的方式还可以实现身份认证功能。

// 创建HTTP客户端
OkHttpClient client = new OkHttpClient.Builder()
        .cookieJar(new CookieJar() {
            // 使用ConcurrentMap存储cookie信息，因为数据在内存中，所以只在程序运行阶段有效，程序结束后即清空
            private ConcurrentMap<String, List<Cookie>> storage = new ConcurrentHashMap<>();

            @Override
            public void saveFromResponse(HttpUrl url, List<Cookie> cookies) {
                String host = url.host();
                if (cookies != null && !cookies.isEmpty()) {
                    storage.put(host, cookies);
                }
            }

            @Override
            public List<Cookie> loadForRequest(HttpUrl url) {
                String host = url.host();
                List<Cookie> list = storage.get(host);
                return list == null ? new ArrayList<>() : list;
            }
        })
        .build();

final String userAgent = "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36";

// 模拟表单登录
Request request = new Request.Builder()
        .url("https://www.oschina.net/action/user/hash_login?from=")
        .post(new FormBody.Builder()
                .add("email", "修改为你自己的帐号")
                .add("pwd", "修改为你自己的密码，使用SHA-1加密")
                .add("verifyCode", "")
                .add("save_login", "1")
                .build())
        .addHeader("User-Agent", userAgent)
        .build();

// 执行模拟登录请求
Response response = client.newCall(request).execute();

// response status
if (!response.isSuccessful()) {
    log.info("code = {}, message = {}", response.code(), response.message());
    return;
} else {
    log.info("登录成功 !");
}


// 请求包含用户状态信息的网页，观察能否正确请求并取得状态信息
request = new Request.Builder()
        .url("https://www.oschina.net/")
        .addHeader("User-Agent", userAgent)
        .get()
        .build();

// 执行GET请求，并在异步回调中处理请求
response = client.newCall(request).execute();

// 打印登录用户名，验证是否获取到了用户的登录信息(状态信息)
if (response.isSuccessful()) {
    String content = response.body().string();

    Matcher matcher = Pattern.compile("<span class="name">(.*)</span>，您好&nbsp;").matcher(content);
    if (matcher.find()) {
        log.info("登录用户：{}", matcher.group(1));
    } else {
        log.info("用户未登录");
    }

}

HttpClient

import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
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.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
 
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
 
public class Test  {
 
    public static void main(String[] args) throws IOException {
        InputStreamReader inputStreamReader = null;
        BufferedReader reader = null;
        String line = null;
        //两个页面参数
        //据我观察这个url不变
        String backUrl = "http%3A%2F%2Fredmine.tvbanywhere.net%2Fredmine%2F";
        String authenticityToken = null;
 
        //创建httpclient对象
        CloseableHttpClient httpClient = HttpClients.createDefault();
 
        //get请求访问这个url是页面
        //获取auth_token
        HttpGet getParam = new HttpGet("http://redmine.tvbanywhere.net/redmine/login");
        CloseableHttpResponse response1 = httpClient.execute(getParam);
        InputStream inputStream1 = response1.getEntity().getContent();
        inputStreamReader = new InputStreamReader(inputStream1);
        reader = new BufferedReader(inputStreamReader);
        while ((line = reader.readLine())!= null){
            if (line.contains("name="authenticity_token"")){
                System.out.println(line);
                String sub1 = line.substring(line.indexOf("value="") + 7);
                authenticityToken = sub1.substring(0, sub1.indexOf("""));
            }
        }
        reader.close();
        inputStreamReader.close();
        inputStream1.close();
        //post 请求是登录操作
        HttpPost dologin = new HttpPost("http://redmine.tvbanywhere.net/redmine/login");
        List<NameValuePair> list = new ArrayList<NameValuePair>();
        list.add(new BasicNameValuePair("authenticity_token",authenticityToken));
        list.add(new BasicNameValuePair("back_url",backUrl));
        list.add(new BasicNameValuePair("username","zhongxiaojian@sunniwell.net"));
        list.add(new BasicNameValuePair("password","zhongxiaojian@sunniwell.net"));
        UrlEncodedFormEntity urlEncodedFormEntity = null;
        urlEncodedFormEntity = new UrlEncodedFormEntity(list);
        dologin.setEntity(urlEncodedFormEntity);
        CloseableHttpResponse response2 = httpClient.execute(dologin);
 
        HttpGet get1 = new HttpGet("http://redmine.tvbanywhere.net/redmine/search?issues=1&q=howard.tang@tvb.com.hk");
        CloseableHttpResponse response3 = httpClient.execute(get1);
        System.err.println("get" + get1.getURI());
        InputStream inputStream3 = response3.getEntity().getContent();
        inputStreamReader = new InputStreamReader(inputStream3);
        reader = new BufferedReader(inputStreamReader);
        while ((line = reader.readLine()) != null){
            System.out.println(line);
        }
    }
}