Spring RestTemplate HTTP Post与参数导致400错误的请求错误

Question

。我 试图Instagram通过Spring Android 从API
获取访问令牌。来自Instagram文档的请求是这样的：

curl \-F 'client_id=CLIENT-ID' \
-F 'client_secret=CLIENT-SECRET' \
-F 'grant_type=authorization_code' \
-F 'redirect_uri=YOUR-REDIRECT-URI' \
-F 'code=CODE' \https://api.instagram.com/oauth/access_token

这是我的请求访问令牌（成功获取请求令牌后）：

 MultiValueMap<String, String> mvm = new LinkedMultiValueMap<String, String>();
    mvm.add("client_id", INSTAGRAM_CILENT_ID);
    mvm.add("client_secret", INSTAGRAM_SECRET);
    mvm.add("grant_type", "authorization_code");
    mvm.add("redirect_uri", CALLBACKURL);
    mvm.add("code", requestToken);

    InstagramResult result = restTemplate .postForObject("https://api.instagram.com/oauth/access_token", mvm, InstagramResult .class);

结果映射类：

public class InstagramLogin {
   public String access_token;
   public InstagramUser user;
}

public class InstagramUser {
   public String id;
   public String username;
   public String full_name;
   public String profile_picture;
}

其余模板：

   RestTemplate restTemplate = new RestTemplate();
    final List<HttpMessageConverter<?>> listHttpMessageConverters = new ArrayList< HttpMessageConverter<?> >();

    listHttpMessageConverters.add(new GsonHttpMessageConverter());
    listHttpMessageConverters.add(new FormHttpMessageConverter());
    listHttpMessageConverters.add(new StringHttpMessageConverter());
    restTemplate.setMessageConverters(listHttpMessageConverters);

但是我总是收到400错误的请求错误。这是我的堆栈跟踪：

04-03 09:32:45.366: W/RestTemplate(31709): POST request for "https://api.instagram.com/oauth/access_token" resulted in 400 (BAD REQUEST); invoking error handler
04-03 09:32:46.857: E//DefaultRequestRunner.java:138(31709): 09:32:46.862 Thread-32787 An exception occurred during request network execution :400 BAD REQUEST
04-03 09:32:46.857: E//DefaultRequestRunner.java:138(31709): org.springframework.web.client.HttpClientErrorException: 400 BAD REQUEST
04-03 09:32:46.857: E//DefaultRequestRunner.java:138(31709):    at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:76)
04-03 09:32:46.857: E//DefaultRequestRunner.java:138(31709):    at org.springframework.web.client.RestTemplate.handleResponseError(RestTemplate.java:524)
04-03 09:32:46.857: E//DefaultRequestRunner.java:138(31709):    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:481)
04-03 09:32:46.857: E//DefaultRequestRunner.java:138(31709):    at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:439)
04-03 09:32:46.857: E//DefaultRequestRunner.java:138(31709):    at org.springframework.web.client.RestTemplate.postForObject(RestTemplate.java:317)

P / s：我确定我的参数值正确，因为我通过curl进行了测试，并且效果很好。

Answer 1

如果请求的内容类型不可接受，则服务器通常会返回HTTP 400。instagram的curl示例使用-F指定多篇文章数据的参数：

-F, --form CONTENT  Specify HTTP multipart POST data (H)

因此，您可能想尝试在RestTemplate请求中显式设置Content-type HTTP标头：

HttpHeaders requestHeaders = new HttpHeaders();
requestHeaders.setContentType(MediaType.MULTIPART_FORM_DATA);
HttpEntity<MultiValueMap<String, String>> requestEntity = new HttpEntity<MultiValueMap<String, String>>(mvm, requestHeaders);
ResponseEntity<InstagramResult> response = restTemplate.exchange(url, HttpMethod.POST, requestEntity, InstagramResult.class);
InstagramResult result = response.getBody();

如注释中前面所述，像fiddler这样的代理工具对于html" target="_blank">调试确实非常有用。这种情况下的挑战是您正在使用SSL，因此如果没有特殊配置，这些工具将无法“查看”加密的通信。