Spotify:发布到 api/token 会给出错误的请求，但在 curl 中工作

Question

我正在尝试通过授权代码流从spotify Web api获取访问令牌。在 curl 中执行请求时，它会按预期返回我令牌：

curl -H "Authorization: Basic Mj...zk=" -d grant_type=authorization_code -d code=AQ...Ew -d redirect_uri=http://localhost:8081/callback https://accounts.spotify.com/api/token

但是，当我尝试在 java 代码中执行相同的请求时，我收到一个 400 错误请求：

    final String url = "https://accounts.spotify.com/api/token";
    CloseableHttpClient client = HttpClients.createDefault();
    HttpPost httpPost = new HttpPost(url);
    List<NameValuePair> params = new ArrayList<NameValuePair>();
    params.add(new BasicNameValuePair("grant_type", "authorization_code"));
    params.add(new BasicNameValuePair("code", req.getParameter("code")));
    params.add(new BasicNameValuePair("redirect_uri ", "http://localhost:8081/callback"));

    httpPost.setEntity(new UrlEncodedFormEntity(params, "UTF-8"));
    httpPost.setHeader(HttpHeaders.AUTHORIZATION,"Basic " +  Base64.encodeBase64String(("2...0" + ":" + "4...9").getBytes()));
    httpPost.setHeader(HttpHeaders.CONTENT_TYPE, "application/x-www-form-urlencoded");
    CloseableHttpResponse response = client.execute(httpPost);
    System.out.println(response);

这是我收到的错误响应：

HttpResponseProxy{HTTP/1.1 400 Bad Request [Server: nginx, Date: Fri, 06 Oct 2017 21:20:39 GMT, Content-Type: application/json, Content-Length: 68, Connection: keep-alive, Keep-Alive: timeout=600] ResponseEntityProxy{[Content-Type: application/json,Content-Length: 68,Chunked: false]}}

我错过了什么或做错了什么？

Answer 1

通过使用 StringEntity 而不是 UrlEncodedFormEntity 自行修复它：

    final String url = "https://accounts.spotify.com/api/token";
    CloseableHttpClient client = HttpClients.createDefault();
    HttpPost httpPost = new HttpPost(url);
    httpPost.setHeader(HttpHeaders.CONTENT_TYPE, "application/x-www-form-urlencoded");
    httpPost.setHeader(HttpHeaders.AUTHORIZATION, "Basic " + Base64.encodeBase64String(("2...0" + ":" + "4...9").getBytes()));
    StringEntity data = new StringEntity("grant_type=authorization_code&&code=" + req.getParameter("code") + "&&redirect_uri=http://localhost:8081/callback");
    httpPost.setEntity(data);
    HttpResponse response = client.execute(httpPost);