安全超文本傳輸協定， HTTPS以保密為目标研發，簡單講HTTPS協定是由SSL+HTTP協定建構的可進行加密傳輸、身份認證的網絡協定，其安全基礎是SSL協定，是以加密的詳細内容請看SSL。全稱Hypertext Transfer Protocol overSecure Socket Layer。句法類同http:體系。用于安全的HTTP資料傳輸。 https:URL表明它使用了HTTP，但HTTPS存在不同于HTTP的預設端口及一個加密/身份驗證層（在HTTP與TCP之間）。

HTTPS和HTTP的差別：

一、 https協定需要到ca申請證書，一般免費證書很少，需要交費。

二、 http是超文本傳輸協定，資訊是明文傳輸， https 則是具有安全性的ssl加密傳輸協定。

三、 http和https使用的是完全不同的連接配接方式，用的端口也不一樣，前者是80，後者是443。

四、 http的連接配接很簡單，是無狀态的； HTTPS協定是由SSL+HTTP協定建構的可進行加密傳輸、身份認證的網絡協定，比http協定安全。

https通路部落格園中的新聞頁面，實作代碼如下：

1 package com.httpclient;
 2 
 3 import java.io.IOException;
 4 import java.security.KeyManagementException;
 5 import java.security.KeyStoreException;
 6 import java.security.NoSuchAlgorithmException;
 7 import java.security.cert.CertificateException;
 8 import java.security.cert.X509Certificate;
 9 
10 import javax.net.ssl.SSLContext;
11 
12 import org.apache.http.HttpEntity;
13 import org.apache.http.client.ClientProtocolException;
14 import org.apache.http.client.methods.CloseableHttpResponse;
15 import org.apache.http.client.methods.HttpGet;
16 import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
17 import org.apache.http.conn.ssl.SSLContextBuilder;
18 import org.apache.http.conn.ssl.TrustStrategy;
19 import org.apache.http.impl.client.CloseableHttpClient;
20 import org.apache.http.impl.client.HttpClients;
21 import org.apache.http.util.EntityUtils;
22 
23 public class yihuqingjiu_https {
24 
25     public static CloseableHttpClient createSSLClientDefault(){
26         try {
27                 SSLContext sslContext = new SSLContextBuilder().loadTrustMaterial(null, new TrustStrategy(){
28                 //信任所有
29                 public boolean isTrusted(X509Certificate[] chain,String authType) throws CertificateException{
30                 return true;
31                 }
32             }).build();
33             SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext);
34             return HttpClients.custom().setSSLSocketFactory(sslsf).build();
35             } catch (KeyManagementException e) {
36                 e.printStackTrace();
37             } catch (NoSuchAlgorithmException e) {
38                 e.printStackTrace();
39             } catch (KeyStoreException e) {
40                 e.printStackTrace();
41             } 
42             return HttpClients.createDefault();
43             }
44     
45     public static void main(String[] args) throws ClientProtocolException, IOException {
46         CloseableHttpClient hp = createSSLClientDefault();
47         HttpGet hg = new HttpGet("https://news.cnblogs.com/");
48         CloseableHttpResponse response = hp.execute(hg);
49         HttpEntity entity = response.getEntity();
50         String content = EntityUtils.toString(entity,"utf-8");
51         System.out.println(content);
52         hp.close();
53 
54     }
55 
56 }

若不添加信任，createSSLClientDefault()方法，會通路失敗

代理，也稱網絡代理，是一種特殊的網絡服務，允許一個網絡終端（一般為用戶端）通過這個服務與另一個網絡終端（一般為伺服器）進行非直接的連接配接。一些網關、路由器等網絡裝置具備網絡代理功能。一般認為代理服務有利于保障網絡終端的隐私或安全，防止攻擊。在使用httpclient進行接口測試的時候，出現需要通路國外的接口請求位址、使用fiddler調試等時候需要先設定代理才能進行。

fiddler會自動給浏覽器加上127.0.0.1：8888，但java代碼中fiddler不會自動給加上。運作上述執行個體，但在fiddler中抓取不到，這就需要進行代理設定了。

代碼實作如下：

1 package com.httpclient;
 2 
 3 import java.io.IOException;
 4 
 5 import org.apache.http.HttpEntity;
 6 import org.apache.http.HttpHost;
 7 import org.apache.http.client.ClientProtocolException;
 8 import org.apache.http.client.config.RequestConfig;
 9 import org.apache.http.client.methods.CloseableHttpResponse;
10 import org.apache.http.client.methods.HttpGet;
11 import org.apache.http.impl.client.CloseableHttpClient;
12 import org.apache.http.impl.client.HttpClients;
13 import org.apache.http.util.EntityUtils;
14 
15 public class yihuqingjiu_Proxy {
16 
17     public static void main(String[] args) throws ClientProtocolException, IOException {
18         //建立httpclient對象
19         CloseableHttpClient httpClient = HttpClients.createDefault();
20         //代理對象
21         HttpHost proxy = new HttpHost("127.0.0.1", 8888, "http");
22         //配置對象
23         RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
24         //建立請求方法的執行個體， 并指定請求url
25         HttpGet httpget=new HttpGet("http://www.qq.com");
26         //使用配置
27         httpget.setConfig(config);
28         CloseableHttpResponse response=httpClient.execute(httpget);
29         HttpEntity entity=response.getEntity();
30         String content=EntityUtils.toString(entity, "utf-8");
31         System.out.println(content);
32         httpClient.close();
33 
34     }
35 
36 }

有很多伺服器，會辨識通路形式是否為浏覽器，若不是浏覽器，會拒絕通路，是以就需要設定請求頭

當我們打開一個網頁時，浏覽器要向網站伺服器發送一個HTTP請求頭，然後網站伺服器根據HTTP請求頭的内容生成當次請求的内容發送給浏覽器。HTTP請求頭提供了關于請求，響應或者其他的發送實體的資訊。 HTTP的頭資訊包括通用頭、請求頭、響應頭和實體頭四個部分。每個頭域由一個域名，冒号（:）和域值三部分組成。

部分請求頭屬性介紹：

accept：浏覽器通過這個頭告訴伺服器，它所支援的資料類型。如： text/html,image/jpeg

accept-Charset：浏覽器通過這個頭告訴伺服器，它支援哪種字元集

accept-encoding：浏覽器通過這個頭告訴伺服器，它支援哪種壓縮格式

accept-language：浏覽器通過這個頭告訴伺服器，它的語言環境

host：浏覽器通過這個頭告訴伺服器，它想通路哪台主機

Connection：表示用戶端與服務連接配接類型

User-Agent（使用者代理），簡稱 UA，它是一個特殊字元串頭，使得伺服器能夠識别用戶端使用的作業系統及版本、 CPU 類型、浏覽器及版本、浏覽器渲染引擎、浏覽器語言、浏覽器插件等

首先看httpclient發送的請求和浏覽器通路的不同之處

httpclient通路：

接口測試——HttpClient工具的https請求、代理設定、請求頭設定、擷取狀态碼和響應頭

浏覽器通路：

可以很清楚的看出，各自的請求頭不同

設定請求頭的方法有三種實作方法：

第一種實作代碼如下

package com.httpclient;

import java.io.IOException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.client.ClientProtocolException;
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.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class yihuqingjiu_header {

    public static void main(String[] args) throws ClientProtocolException, IOException {
        //建立httpclient對象
        CloseableHttpClient httpClient = HttpClients.createDefault();
        //代理對象
        HttpHost proxy = new HttpHost("127.0.0.1", 8888, "http");
        //配置對象
        RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
        //建立請求方法的執行個體， 并指定請求url
        HttpGet httpget=new HttpGet("http://www.qq.com");
        //使用配置
        httpget.setConfig(config);
        //設定請求頭
        httpget.setHeader("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8");
        httpget.setHeader("Accept-Encoding", "gzip, deflate");
        httpget.setHeader("Accept-Language", "zh-CN,zh;q=0.8");
        httpget.setHeader("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.91 Safari/537.36");
        CloseableHttpResponse response=httpClient.execute(httpget);
        HttpEntity entity=response.getEntity();
        String content=EntityUtils.toString(entity, "utf-8");
        System.out.println(content);
        httpClient.close();

    }

}

然後到fiddler中檢視請求頭資訊，和浏覽器通路一樣了，如下圖所示：

第二中實作方式，建立代理對象，代碼如下：

1 package com.httpclient;
 2 
 3 import java.io.IOException;
 4 
 5 import org.apache.http.HttpEntity;
 6 import org.apache.http.HttpHost;
 7 import org.apache.http.client.ClientProtocolException;
 8 import org.apache.http.client.config.RequestConfig;
 9 import org.apache.http.client.methods.CloseableHttpResponse;
10 import org.apache.http.client.methods.HttpGet;
11 import org.apache.http.entity.mime.Header;
12 import org.apache.http.impl.client.CloseableHttpClient;
13 import org.apache.http.impl.client.HttpClients;
14 import org.apache.http.message.BasicHeader;
15 import org.apache.http.util.EntityUtils;
16 
17 import com.google.common.net.HttpHeaders;
18 
19 public class yihuqingjiu_header1 {
20 
21     public static void main(String[] args) throws ClientProtocolException, IOException {
22         //建立httpclient對象
23         CloseableHttpClient httpClient = HttpClients.createDefault();
24         //代理對象
25         HttpHost proxy = new HttpHost("127.0.0.1", 8888, "http");
26         //配置對象
27         RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
28         //建立請求方法的執行個體， 并指定請求url
29         HttpGet httpget=new HttpGet("http://www.qq.com");
30         //使用配置
31         httpget.setConfig(config);
32         //設定請求頭,對象實作
33         BasicHeader a = new BasicHeader(HttpHeaders.ACCEPT, "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8");
34         httpget.setHeader(a);
35         CloseableHttpResponse response=httpClient.execute(httpget);
36         HttpEntity entity=response.getEntity();
37         String content=EntityUtils.toString(entity, "utf-8");
38         System.out.println(content);
39         httpClient.close();
40 
41     }
42 
43 }

第三種實作方式，數組實作，代碼如下：

package com.httpclient;

import java.io.IOException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.client.ClientProtocolException;
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.entity.mime.Header;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicHeader;
import org.apache.http.util.EntityUtils;

import com.google.common.net.HttpHeaders;

public class yihuqingjiu_header2 {

    public static void main(String[] args) throws ClientProtocolException, IOException {
        //建立httpclient對象
        CloseableHttpClient httpClient = HttpClients.createDefault();
        //代理對象
        HttpHost proxy = new HttpHost("127.0.0.1", 8888, "http");
        //配置對象
        RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
        //建立請求方法的執行個體， 并指定請求url
        HttpGet httpget=new HttpGet("http://www.qq.com");
        //使用配置
        httpget.setConfig(config);
        //設定請求頭，數組實作
        BasicHeader[] header = new BasicHeader[2];
        //寫法1
        //BasicHeader a = new BasicHeader(HttpHeaders.ACCEPT, "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8");
        //header[0]=a;
        //寫法2
        header[0] = new BasicHeader(HttpHeaders.ACCEPT, "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8");
        header[1] = new BasicHeader(HttpHeaders.ACCEPT_LANGUAGE, "zh-CN,zh;q=0.8");
        httpget.setHeaders(header);
        CloseableHttpResponse response=httpClient.execute(httpget);
        HttpEntity entity=response.getEntity();
        String content=EntityUtils.toString(entity, "utf-8");
        System.out.println(content);
        httpClient.close();

    }

}

可以擷取Headers中的資訊，也就是Headers中的第一行資料，擷取狀态碼實作代碼如下：

1 package com.httpclient;
 2 
 3 import java.io.IOException;
 4 
 5 import org.apache.http.HttpEntity;
 6 import org.apache.http.HttpHost;
 7 import org.apache.http.client.ClientProtocolException;
 8 import org.apache.http.client.config.RequestConfig;
 9 import org.apache.http.client.methods.CloseableHttpResponse;
10 import org.apache.http.client.methods.HttpGet;
11 import org.apache.http.impl.client.CloseableHttpClient;
12 import org.apache.http.impl.client.HttpClients;
13 import org.apache.http.util.EntityUtils;
14 
15 public class yihuqingjiu_response1 {
16 
17     public static void main(String[] args) throws ClientProtocolException, IOException {
18         //建立httpclient對象
19         CloseableHttpClient httpClient = HttpClients.createDefault();
20         //代理對象
21         HttpHost proxy = new HttpHost("127.0.0.1", 8888, "http");
22         //配置對象
23         RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
24         //建立請求方法的執行個體， 并指定請求url
25         HttpGet httpget=new HttpGet("http://www.qq.com");
26         //使用配置
27         httpget.setConfig(config);
28         CloseableHttpResponse response=httpClient.execute(httpget);
29         HttpEntity entity=response.getEntity();
30         String content=EntityUtils.toString(entity, "utf-8");
31         System.out.println(content);
32         System.out.println("------------------------------------");
33         //擷取響應狀态碼
34         int code = response.getStatusLine().getStatusCode();
35         System.out.println("code:"+code);
36         String a = response.getStatusLine().toString();
37         System.out.println("a:"+a);    
38         httpClient.close();
39     }
40 
41 }

響應頭也是Headers中的内容，如下圖所示：

實作代碼如下所示，裡面包含多種實作方式，但輸出的内容都差不多

1 package com.httpclient;
 2 
 3 import java.io.IOException;
 4 
 5 import org.apache.http.Header;
 6 import org.apache.http.HttpEntity;
 7 import org.apache.http.HttpHost;
 8 import org.apache.http.client.ClientProtocolException;
 9 import org.apache.http.client.config.RequestConfig;
10 import org.apache.http.client.methods.CloseableHttpResponse;
11 import org.apache.http.client.methods.HttpGet;
12 import org.apache.http.impl.client.CloseableHttpClient;
13 import org.apache.http.impl.client.HttpClients;
14 import org.apache.http.util.EntityUtils;
15 
16 public class yihuqingjiu_response {
17 
18     public static void main(String[] args) throws ClientProtocolException, IOException {
19         //建立httpclient對象
20         CloseableHttpClient httpClient = HttpClients.createDefault();
21         //代理對象
22         HttpHost proxy = new HttpHost("127.0.0.1", 8888, "http");
23         //配置對象
24         RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
25         //建立請求方法的執行個體， 并指定請求url
26         HttpGet httpget=new HttpGet("http://www.qq.com");
27         //使用配置
28         httpget.setConfig(config);
29         CloseableHttpResponse response=httpClient.execute(httpget);
30         HttpEntity entity=response.getEntity();
31         String content=EntityUtils.toString(entity, "utf-8");
32         System.out.println(content);
33         System.out.println("------------------------------------");
34         //接收響應頭
35         //擷取一個響應頭，first和last兩個方法指的是，當裡面有兩個一樣的響應時，就去第一個或最後一個
36         String server = response.getFirstHeader("Server").toString();
37         System.out.println(server);
38         //擷取所有響應頭
39         Header[] header = response.getAllHeaders();
40         //周遊輸出所有
41         for(Header as:header){
42             System.out.println(as.toString());
43         }
44         System.out.println("------------------------------------");
45         //輸出name
46         for(Header name:header){
47             System.out.println(name.getName());
48         }
49         System.out.println("------------------------------------");
50         //輸出value
51         for(Header value:header){
52             System.out.println(value.getValue());
53         }
54         //輸出第一個
55         //System.out.println(header[0].toString());
56         //輸出數組大小
57         Header[] ha = response.getHeaders("Server");
58         System.out.println(ha.length);
59         httpClient.close();
60 
61     }
62 
63 }

周遊輸出所有響應頭内容，如下所示：

接口測試——HttpClient工具的https請求、代理設定、請求頭設定、擷取狀态碼和響應頭

目錄

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HttpClient post 請求執行個體

HttpComponents —— HTTP請求（HttpRequest）

HttpClient中，使用HttpDelete時無法攜帶body的解決辦法

接口自動化落地（二：HttpClient+testNG實作對接口的測試及校驗）

Python3内置http.client，urllib.request及三方庫requests發送請求對比

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