如何使用Apache HTTPClient 4.5发送带有JSON参数的POST。获得415不支持的媒体类型

Question

我尝试使用一组JSON参数向我的服务器发送POST请求（使用Apache HTTPClient 4.5）。我已经关注了一些SO问题，但遇到了问题。

当我使用javascript控制台发送请求时，它可以正常工作！像这样：

//Using JS console, I send a POST request and it works.
$.post('/createConfigData', {
    "tailSign": "A7ALE",
    "active": "Y"
});
//Get back 201

当我使用 Apache HTTPClient 4.5 尝试执行上述操作时，我会返回 415不支持的媒体类型：

HttpPost httppost = new HttpPost('/createConfigData');
String jsondata = "{\"tailSign\": \"A7ALE\",\"active\": \"Y\"}";

StringEntity jsonparam = new StringEntity(jsondata);
jsonparam.setContentType("application/json;charset=utf-8");
jsonparam.setChunked(true);

httppost.addHeader("content-type", "application/x-www-form-urlencoded;charset=UTF-8");
httppost.setEntity(jsonparam);

httpresponse = httpclient.execute(target, httppost);

我从工作请求获得的数据是：

• 请求标题：
  • 主持人：＆＃34; mysite.com＆＃34;
  • User-Agent：＆＃34; Mozilla / 5.0（X11; Ubuntu; Linux x86_64; rv：25.0）Gecko / 20100101 Firefox / 25.0＆＃34;
  • 接受："*/*"
  • 接受语言：＆＃34; en-US，en; q = 0.5＆＃34;
  • 接受编码：＆＃34; gzip，deflate＆＃34;
  • 内容类型：＆＃34; application / x-www-form-urlencoded;字符集= UTF-8＆＃34;
  • Referer：＆＃34; mysite.com/index.html"
  • 内容长度：＆＃34; 288＆＃34;
  • Cookie：＆＃34; JSESSIONID = ...＆＃34;
  • 代理授权：＆＃34;基本......＆＃34;
  • 连接：＆＃34; keep-alive＆＃34;
  • Pragma：＆＃34; no-cache＆＃34;
  • 缓存控制：＆＃34; no-cache＆＃34;
• 响应标题：
  • 年龄：＆＃34; 0＆＃34;
  • 连接：＆＃34; Keep-Alive＆＃34;
  • 内容类型：＆＃34; application / json; charset = UTF-8＆＃34;
  • 日期：＆＃34; 2016年10月19日星期三17:57:34 GMT＆＃34;
  • 服务器：＆＃34; Apache-Coyote / 1.1＆＃34;
  • 转移编码：＆＃34; chunked＆＃34;

我对设置内容类型的位置感到有点困惑，无论是实体还是 httppost

=======================

更多测试用例

将 httpost＆＃39; 内容类型设置为 json ，可以 400

HttpPost httppost = new HttpPost('/createConfigData');
String jsondata = "{\"tailSign\": \"A7ALE\",\"active\": \"Y\"}";

StringEntity jsonparam = new StringEntity(jsondata);
jsonparam.setChunked(true);

httppost.addHeader("content-type", "application/json;charset=UTF-8");
httppost.setEntity(jsonparam);

httpresponse = httpclient.execute(target, httppost);

将 httpost 内容类型设置为 x-www-form-urlencoded ，可以 415

HttpPost httppost = new HttpPost('/createConfigData');
String jsondata = "{\"tailSign\": \"A7ALE\",\"active\": \"Y\"}";

StringEntity jsonparam = new StringEntity(jsondata);
jsonparam.setChunked(true);

httppost.addHeader("content-type", "application/x-www-form-urlencoded;charset=UTF-8");
httppost.setEntity(jsonparam);

httpresponse = httpclient.execute(target, httppost);

我也尝试添加这一行：

httppost.addHeader("Accept", "*/*");

==================

解

使用 wireshark 我能够发现有一条错误消息与400错误请求一起出现！这只是我的JSON不正确。

HTTP/1.1 400 Bad Request
Server: Apache-Coyote/1.1
Content-Type: application/json;charset=UTF-8
Transfer-Encoding: chunked
Date: Wed, 19 Oct 2016 21:33:25 GMT
Proxy-Connection: Keep-Alive
Connection: Keep-Alive

{"code":400,"message":"Field ConfigName is Null, Invalid Value for Seat Count, Missing counts for DSU, ICMT, SVDU, TPMU, Login user details not found, Please enter valid lruData","fleetData":{"airlineData":null,"dimAircraftJson":null,"configData":null}}

Answer 1

您获得 415不支持的媒体类型，因为您已将内容类型标头覆盖为 application / x-www-form-urlencoded;字符集= UTF-8 即可。只需将其更改为：

HttpPost httppost = new HttpPost('/createConfigData');
String jsondata = "{\"tailSign\": \"A7ALE\",\"active\": \"Y\"}";
StringEntity jsonparam = new StringEntity(jsondata);
jsonparam.setChunked(true);

httppost.addHeader("content-type", "application/json;charset=UTF-8");
httppost.setEntity(jsonparam);

httpresponse = httpclient.execute(target, httppost);