public bool TryGetAccessToken(string verificationCode, out GoogleOAuthException error)
{
error = null;
try
{
GetAccessToken(verificationCode);
return true;
}
catch (GoogleOAuthException ex)
{
error = ex;
return false;
}
}
public bool GetAccessToken(string verificationCode)
{
var p = new NameValueCollection();
p.Add("client_id", this.ClientId);
p.Add("client_secret", this.ClientSecret);
p.Add("code", verificationCode);
p.Add("redirect_uri", string.IsNullOrEmpty(this.RedirectUrl) ? OobRedirectUrl : this.RedirectUrl);
p.Add("grant_type", "authorization_code");
var url = Util.BuildUrl(OobRedirectUrl, p);
var data = Util.DownloadUrl(url);
if (!parseToken(data))
{
var ex = new GoogleOAuthException("Failed to get Access Token. Check ServerResponse for Details.");
ex.ServerResponse = data;
throw ex;
}
return true;
}
public bool TryRefreshAccessToken(out GoogleOAuthException error)
{
error = null;
try
{
RefreshAccessToken();
return true;
}
catch (GoogleOAuthException ex)
{
error = ex;
return false;
}
}
public bool GetAccessToken(string verificationCode)
{
if (string.IsNullOrEmpty(verificationCode))
throw new GoogleOAuthException("Missing Verification Code!");
//Again make sure these are in alpha order
var p = new NameValueCollection();
p.Add("oauth_consumer_key", this.ConsumerKey);
p.Add("oauth_nonce", Util.RandomInt64().ToString());
p.Add("oauth_signature_method", "HMAC-SHA1");
p.Add("oauth_timestamp", Util.EpochNow().ToString());
p.Add("oauth_token", this.Token);
p.Add("oauth_verifier", verificationCode);
p.Add("oauth_version", "1.0");
//Generating the signature, this time we have a TokenSecret we must include
p.Add("oauth_signature", Util.GenerateSignature(OAuthGetAccessTokenUrl, p, this.ConsumerSecret, this.TokenSecret));
//Get the response
var url = Util.BuildUrl(OAuthGetAccessTokenUrl, p);
var data = Util.DownloadUrl(url);
var responseParameters = Util.ParseQueryString(data);
//Parse out the tokens in the response
this.Token = responseParameters["oauth_token"] ?? "";
this.TokenSecret = responseParameters["oauth_token_secret"] ?? "";
//If we have no tokens, we had an issue
if (string.IsNullOrEmpty(this.Token) || string.IsNullOrEmpty(this.TokenSecret))
{
var ex = new GoogleOAuthException("Missing Token or TokenSecret in response. Check ServerResponse.");
ex.ServerResponse = data;
throw ex;
}
//Everything went ok!
return true;
}
/// <summary>
/// Authorizes an account with OAuth for the specified Google scopes and gets the URL to display to the user for further authorization.
/// You should call GetAccessToken() next with the verification code returned after the user Grants your application access.
/// </summary>
/// <returns>Returns the Authorization URL to display for the user.</returns>
public string GetAuthUrl()
{
//Step 1: Get Request Token
// IMPORTANT NOTE: For the GenerateSignature to work properly all the parameters in this
// collection must be in alpha order!!!
var p = new NameValueCollection();
p.Add("oauth_callback", this.CallbackUrl);
p.Add("oauth_consumer_key", this.ConsumerKey);
p.Add("oauth_nonce", Util.RandomInt64().ToString());
p.Add("oauth_signature_method", "HMAC-SHA1");
p.Add("oauth_timestamp", Util.EpochNow().ToString());
p.Add("oauth_version", "1.0");
p.Add("scope", string.Join(" ", Scopes));
p.Add("xoauth_displayname", DisplayName);
//Add the last paramaeter which uses the existing ones to generate a signature
p.Add("oauth_signature", Util.GenerateSignature(OAuthGetRequestTokenUrl, p, this.ConsumerSecret, null));
//Build the url and download the data
var url = Util.BuildUrl(OAuthGetRequestTokenUrl, p);
var data = Util.DownloadUrl(url);
var responseParameters = Util.ParseQueryString(data);
//Parse out the tokens in the response
this.Token = responseParameters["oauth_token"] ?? "";
this.TokenSecret = responseParameters["oauth_token_secret"] ?? "";
//If the tokens aren't there, we had an issue
if (string.IsNullOrEmpty(this.Token) || string.IsNullOrEmpty(this.TokenSecret))
{
var ex = new GoogleOAuthException("Missing Token or TokenSecret in response. Check ServerResponse.");
ex.ServerResponse = data;
throw ex;
}
//Build the url to show the user
url = string.Format("{0}?oauth_token={1}", OAuthAuthorizeTokenUrl, this.Token);
//Mobile support can be forced
if (Mobile)
url += "&btmpl=mobile";
return url;
}
public bool TryGetAuthUrl(out string authUrl, out GoogleOAuthException error)
{
authUrl = string.Empty;
error = null;
try
{
authUrl = GetAuthUrl();
return true;
}
catch (GoogleOAuthException ex)
{
error = ex;
return false;
}
}
/// <summary>
/// Validates the given token and tokenSecret to ensure it is still valid for the given scopes
/// </summary>
/// <param name="token">Access Token returned from Authorization</param>
/// <param name="tokenSecret">Access Token Secret returned from Authorization</param>
/// <returns>True if the Token is still valid and is valid for the given scopes</returns>
public bool ValidateTokens(string token, string tokenSecret)
{
//This is largely unadvertised as a means to validate OAuth Token and token scope.
// This is the documented way to get AuthSub info, but it works for OAuth too!
//Important that these parameters are in alpha order
var p = new NameValueCollection();
p.Add("oauth_consumer_key", this.ConsumerKey);
p.Add("oauth_nonce", Util.RandomInt64().ToString());
p.Add("oauth_signature_method", "HMAC-SHA1");
p.Add("oauth_timestamp", Util.EpochNow().ToString());
p.Add("oauth_token", token);
p.Add("oauth_version", "1.0");
//Build the signature
p.Add("oauth_signature", Util.GenerateSignature(OAuthVerifyTokensUrl, p, this.ConsumerSecret, tokenSecret));
//Get a response
var url = Util.BuildUrl(OAuthVerifyTokensUrl, p);
var data = Util.DownloadUrl(url);
//The respone from google comes in lines
var lines = data.Split('\n');
//No lines parsed? had an issue
if (lines == null || lines.Length <= 0)
throw new GoogleOAuthException("Empty Response from Validation Call");
//We want to find all the valid scopes returned
// eg format: Scope=...\nScope2=... etc.
var validScopes = new List<string>();
//There will be a line Secure=true if the token is valid still
bool secure = false;
//Parse out the lines
foreach (var line in lines)
{
if (line.StartsWith("Scope", StringComparison.InvariantCultureIgnoreCase)
&& line.Contains('='))
{
var scope = line.Substring(line.IndexOf('=') + 1);
if (!string.IsNullOrEmpty(scope))
validScopes.Add(scope);
}
else if (line.StartsWith("Secure=true", StringComparison.InvariantCultureIgnoreCase))
secure = true;
}
//Find if any required scopes are missing from the valid scopes
var missingScopes = from s in this.Scopes
where !validScopes.Exists(vs => vs.Equals(s, StringComparison.InvariantCultureIgnoreCase))
select s;
if (missingScopes.Count() > 0)
{
var ex = new GoogleOAuthException("Access Token is not valid for one or more requested scopes");
ex.Data.Add("MissingScopes", missingScopes.ToArray());
throw ex;
}
if (!secure)
throw new GoogleOAuthException("Validation: Account not Secured");
return true;
}
public bool TryValidateTokens(string token, string tokenSecret, out GoogleOAuthException error)
{
error = null;
try
{
return ValidateTokens(token, tokenSecret);
}
catch (GoogleOAuthException ex)
{
error = ex;
return false;
}
}
