如何獲取谷歌oauth的訪問令牌？

Question

我正在使用C＃（ASP.NET）。我想使用Google oauth在我的應用程序中訪問用戶個人資料的詳細信息。我成功獲取授權碼，但在獲取訪問令牌方面遇到問題。 我更喜歡Google tutorials。在教程中，我讀到我必須發送請求並從Google獲得響應。爲此，我使用System.Net.HttpWebRequest/HttpWebResponse（我是否正確）。我用這個代碼....

byte[] buffer = Encoding.ASCII.GetBytes("?code=" + code + "&client_id=xxx&client_secret=xxx&redirect_uri=xxxx&grant_type=authorization_code"); 
HttpWebRequest req = (HttpWebRequest)WebRequest.Create("http://accounts.google.com"); 
req.Method = "POST"; 
req.ContentType = "application/x-www-form-urlencoded"; 
req.ContentLength = buffer.Length; 

Stream strm = req.GetRequestStream(); 
strm.Write(buffer, 0, buffer.Length); 
strm.Close(); 

HttpWebResponse resp = (HttpWebResponse)req.GetResponse(); 
Response.Write(((HttpWebResponse)resp).StatusDescription); 

但是，我得到了錯誤：

The remote server returned an error: (405) Method Not Allowed.

更新：這裏變量code是授權碼。

Answer 1

我想您發送POST請求到錯誤的端點，正確的是https://accounts.google.com/o/oauth2/token

Answer 2

正如我曾在谷歌實施的權威性過程中類似的問題，我會後，工程的代碼..最後提到的問題：錯誤（400）錯誤的請求可能由導致'？'引起在上面的代碼..

string codeClient = "code="+ t +"&client_id=number.apps.googleusercontent.com&"; 
string secretUri = "client_secret=yoursecret&" + "redirect_uri=path&" 
     + "grant_type=authorization_code"; 
postString = codeClient + secretUri; 

string url = "https://accounts.google.com/o/oauth2/token"; 

HttpWebRequest request = (HttpWebRequest) WebRequest.Create(url.ToString()); 
request.Method = "POST"; 
request.ContentType = "application/x-www-form-urlencoded"; 

UTF8Encoding utfenc = new UTF8Encoding(); 
byte[] bytes = utfenc.GetBytes(postString); 
Stream os = null; 
try 
{ 
     request.ContentLength = bytes.Length; 
     os = request.GetRequestStream(); 
     os.Write(bytes, 0, bytes.Length); 
} 
catch 
{ } 

try 
{ 
     HttpWebResponse webResponse = (HttpWebResponse) request.GetResponse(); 
     Stream responseStream = webResponse.GetResponseStream(); 
     StreamReader responseStreamReader = new StreamReader(responseStream); 
     result = responseStreamReader.ReadToEnd();//parse token from result 

Answer 3

我的代碼工作，我在上面兩行中犯了錯誤。它應該是這樣的

byte[] buffer = Encoding.ASCII.GetBytes("code=" + code + "&client_id=xxx&client_secret=xxx&redirect_uri=xxxx&grant_type=authorization_code"); 
HttpWebRequest req = (HttpWebRequest)WebRequest.Create("https://accounts.google.com/o/oauth2/token"); 

剩餘的代碼是正確的。

Answer 4

最初的請求似乎有些過時。但是我發現Google的代碼示例包含很多「最佳實踐」管家代碼，這些代碼很難與基本操作分離。

我最近發佈了一個文檔，它將所有REST操作都表示爲curl命令。每種語言都很難懂，但捲曲看起來很普遍。大多數人都知道，否則，這很容易掌握。在我的捲曲示例中，-d標誌指示POST操作。否則，參數將附加到URL。

http://www.tqis.com/eloquency/googlecalendar.htm

Answer 5

public string ReceiveTokenGmail(string code, string GoogleWebAppClientID, string GoogleWebAppClientSecret, string RedirectUrl) 
{ 
    string postString = "code=" + code + "&client_id=" + GoogleWebAppClientID + @"&client_secret=" + GoogleWebAppClientSecret + "&redirect_uri=" + RedirectUrl; 

    string url = "https://accounts.google.com/o/oauth2/token"; 

    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url.ToString()); 
    request.Method = "POST"; 
    request.ContentType = "application/x-www-form-urlencoded"; 

    UTF8Encoding utfenc = new UTF8Encoding(); 
    byte[] bytes = utfenc.GetBytes(postString); 
    Stream os = null; 
    try 
    { 
     request.ContentLength = bytes.Length; 
     os = request.GetRequestStream(); 
     os.Write(bytes, 0, bytes.Length); 
    } 
    catch 
    { } 
    string result = ""; 

    HttpWebResponse webResponse = (HttpWebResponse)request.GetResponse(); 
    Stream responseStream = webResponse.GetResponseStream(); 
    StreamReader responseStreamReader = new StreamReader(responseStream); 
    result = responseStreamReader.ReadToEnd(); 

    return result; 
}