Cannot load System.Threading.Tasks assembly, using Google Calendar API
SOLVED !
Huge thank to Sam Leach
Here is a sample of my working app.config file:
<configuration>
...
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="System.Threading.Tasks" publicKeyToken="B03F5F7F11D50A3A" culture="neutral"/>
<bindingRedirect oldVersion="0.0.0.0-2.5.19.0" newVersion="2.5.19.0"/>
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Net.Http" publicKeyToken="B03F5F7F11D50A3A" culture="neutral"/>
<bindingRedirect oldVersion="0.0.0.0-2.1.10.0" newVersion="2.1.10.0"/>
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Net.Http.Primitives" publicKeyToken="B03F5F7F11D50A3A" culture="neutral"/>
<bindingRedirect oldVersion="0.0.0.0-2.1.10.0" newVersion="2.1.10.0"/>
</dependentAssembly>
</assemblyBinding>
</runtime>
</configuration>
I have also found that source
EDIT: The original question is below the line.
I am using the .NET 4.0 Framework and from my research I know that the System.Threading.Tasks assembly is no longer needed (because it's included automatically). Am I wrong about this?
If I am right, I am now pretty sure that the error is raised because the version of System.Threading.Tasks used by the developers of the google-api-dotnet-client and the one used by Visual Studio 2010 are different.
I noticed that when inspecting the behavior of my app when I remove some lines.
And these lines came out:
gcal = new CalendarService(new BaseClientService.Initializer()
{
Authenticator = auth,
ApplicationName = APP_NAME,
});
So, my new question is:
Is there a way to force the usage of one specific version of a reference assembly in VS2010 ?
Thank you for helping me, I am sure it will help lots of people because the google-calendar-api-v3 is badly documented.
Kind regards, Bruno.
My problem is that I can't get access to the Google API as a service through VisualStudio.
I get this error:
L'exception System.IO.FileLoadException n'a pas été gérée
Message=Impossible de charger le fichier ou l'assembly 'System.Threading.Tasks, Version=1.5.11.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' ou une de ses dépendances. La définition trouvée du manifeste de l'assembly ne correspond pas à la référence de l'assembly. (Exception de HRESULT : 0x80131040)
Source=MVMA
FileName=System.Threading.Tasks, Version=1.5.11.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
FusionLog==== Informations d'état de liaison préalable ===
JRN : utilisateur = MODAL\brbo
JRN : DisplayName = System.Threading.Tasks, Version=1.5.11.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
(Fully-specified)
JRN : Appbase = file:///C:/Users/brbo/Documents/Visual Studio 2010/Projects/MVMA-V5.0 (With Gantt)/MVMA/bin/Debug/
JRN : PrivatePath initial = NULL
Assembly appelant : Google.Apis, Version=1.4.0.28227, Culture=neutral, PublicKeyToken=null.
===
JRN : cette liaison démarre dans le contexte de chargement de default.
JRN : utilisation du fichier de configuration de l'application : C:\Users\brbo\Documents\Visual Studio 2010\Projects\MVMA-V5.0 (With Gantt)\MVMA\bin\Debug\MVMA.vshost.exe.Config
JRN : utilisation du fichier de configuration d'hôte :
JRN : utilisation du fichier de configuration de l'ordinateur à partir de C:\Windows\Microsoft.NET\Framework64\v4.0.30319\config\machine.config.
JRN : référence post-stratégie : System.Threading.Tasks, Version=1.5.11.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
JRN : tentative de téléchargement de la nouvelle URL file:///C:/Users/brbo/Documents/Visual Studio 2010/Projects/MVMA-V5.0 (With Gantt)/MVMA/bin/Debug/System.Threading.Tasks.DLL.
AVT : la comparaison du nom de l'assembly a entraîné l'incompatibilité : Version principale
ERR : impossible de terminer l'installation de l'assembly (hr = 0x80131040). Détection terminée.
StackTrace:
à MVMA.Classes.GoogleCalendar.BuildCalendarService()
à System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
à System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
à System.Threading.ThreadHelper.ThreadStart()
And here is my classes (same namespace) which tries to connect to the Google Calendar API v3 using Json Web Tokens:
public class GoogleCalendar
{
// Chaînes d'accès aux services Google
public const string APP_NAME = "HIDDEN";
public const string CLIENT_ID = "HIDDEN";
public const string CLIENT_SECRET = "HIDDEN";
public const string SERVICE_CLIENT_ID = "HIDDEN";
public const string EMAIL_ADDRESS = "HIDDEN";
public const string PUB_KEY = "HIDDEN";
public const string PRIV_KEY_PATH = @"C:\MVMA\HIDDEN-privatekey.p12";
public const string PRIV_KEY_SECRET = "notasecret";
public const string SIMPLE_API_KEY = "HIDDEN";
public const string SCOPE_CALENDAR = "https://www.googleapis.com/auth/calendar";
public const string SCOPE_CALENDAR_READONLY = "https://www.googleapis.com/auth/calendar.readonly";
private static CalendarService gcal;
public static void ImportFromMVMA()
{
Thread yat = new Thread(new ThreadStart(BuildCalendarService));
yat.Start();
}
// Permet de récupérer le service calendrier
// Define the method that receives a callback when the results are available.
private static void BuildCalendarService() {
var certificate = new X509Certificate2(PRIV_KEY_PATH, PRIV_KEY_SECRET, X509KeyStorageFlags.Exportable);
var privateKey = certificate.Export(X509ContentType.Cert);
var provider = new AssertionFlowClient(GoogleAuthenticationServer.Description, certificate)
{
ServiceAccountId = EMAIL_ADDRESS,
Scope = SCOPE_CALENDAR
};
var auth = new OAuth2Authenticator<AssertionFlowClient>(provider, AssertionFlowClient.GetState);
gcal = new CalendarService(new BaseClientService.Initializer()
{
Authenticator = auth,
ApplicationName = APP_NAME,
});
}
}
public enum JwtHashAlgorithm
{
RS256,
HS384,
HS512
}
public class JsonWebToken
{
private static Dictionary<JwtHashAlgorithm, Func<byte[], byte[], byte[]>> HashAlgorithms;
static JsonWebToken()
{
HashAlgorithms = new Dictionary<JwtHashAlgorithm, Func<byte[], byte[], byte[]>>
{
{ JwtHashAlgorithm.RS256, (key, value) => { using (var sha = new HMACSHA256(key)) { return sha.ComputeHash(value); } } },
{ JwtHashAlgorithm.HS384, (key, value) => { using (var sha = new HMACSHA384(key)) { return sha.ComputeHash(value); } } },
{ JwtHashAlgorithm.HS512, (key, value) => { using (var sha = new HMACSHA512(key)) { return sha.ComputeHash(value); } } }
};
}
public static string Encode(object payload, string key, JwtHashAlgorithm algorithm)
{
return Encode(payload, Encoding.UTF8.GetBytes(key), algorithm);
}
public static string Encode(object payload, byte[] keyBytes, JwtHashAlgorithm algorithm)
{
var segments = new List<string>();
var header = new { alg = algorithm.ToString(), typ = "JWT" };
byte[] headerBytes = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(header, Formatting.None));
byte[] payloadBytes = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(payload, Formatting.None));
segments.Add(Base64UrlEncode(headerBytes));
segments.Add(Base64UrlEncode(payloadBytes));
var stringToSign = string.Join(".", segments.ToArray());
var bytesToSign = Encoding.UTF8.GetBytes(stringToSign);
byte[] signature = HashAlgorithms[algorithm](keyBytes, bytesToSign);
segments.Add(Base64UrlEncode(signature));
return string.Join(".", segments.ToArray());
}
public static string Decode(string token, string key)
{
return Decode(token, key, true);
}
public static string Decode(string token, string key, bool verify)
{
var parts = token.Split('.');
var header = parts[0];
var payload = parts[1];
byte[] crypto = Base64UrlDecode(parts[2]);
var headerJson = Encoding.UTF8.GetString(Base64UrlDecode(header));
var headerData = JObject.Parse(headerJson);
var payloadJson = Encoding.UTF8.GetString(Base64UrlDecode(payload));
var payloadData = JObject.Parse(payloadJson);
if (verify)
{
var bytesToSign = Encoding.UTF8.GetBytes(string.Concat(header, ".", payload));
var keyBytes = Encoding.UTF8.GetBytes(key);
var algorithm = (string)headerData["alg"];
var signature = HashAlgorithms[GetHashAlgorithm(algorithm)](keyBytes, bytesToSign);
var decodedCrypto = Convert.ToBase64String(crypto);
var decodedSignature = Convert.ToBase64String(signature);
if (decodedCrypto != decodedSignature)
{
throw new ApplicationException(string.Format("Invalid signature. Expected {0} got {1}", decodedCrypto, decodedSignature));
}
}
return payloadData.ToString();
}
private static JwtHashAlgorithm GetHashAlgorithm(string algorithm)
{
switch (algorithm)
{
case "RS256": return JwtHashAlgorithm.RS256;
case "HS384": return JwtHashAlgorithm.HS384;
case "HS512": return JwtHashAlgorithm.HS512;
default: throw new InvalidOperationException("Algorithm not supported.");
}
}
// from JWT spec
private static string Base64UrlEncode(byte[] input)
{
var output = Convert.ToBase64String(input);
output = output.Split('=')[0]; // Remove any trailing '='s
output = output.Replace('+', '-'); // 62nd char of encoding
output = output.Replace('/', '_'); // 63rd char of encoding
return output;
}
// from JWT spec
private static byte[] Base64UrlDecode(string input)
{
var output = input;
output = output.Replace('-', '+'); // 62nd char of encoding
output = output.Replace('_', '/'); // 63rd char of encoding
switch (output.Length % 4) // Pad with trailing '='s
{
case 0: break; // No pad chars in this case
case 2: output += "=="; break; // Two pad chars
case 3: output += "="; break; // One pad char
default: throw new System.Exception("Illegal base64url string!");
}
var converted = Convert.FromBase64String(output); // Standard base64 decoder
return converted;
}
}
public class GoogleJsonWebToken
{
public static string GetAccessToken(string email, string certificateFilePath, string serviceScope)
{
var utc0 = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
var issueTime = DateTime.Now;
var iat = (int)issueTime.Subtract(utc0).TotalSeconds;
var exp = (int)issueTime.AddMinutes(55).Subtract(utc0).TotalSeconds; // Expiration time is up to 1 hour, but lets play on safe side
var payload = new
{
iss = email,
scope = serviceScope,
aud = "https://accounts.google.com/o/oauth2/token",
exp = exp,
iat = iat
};
var certificate = new X509Certificate2(certificateFilePath, GoogleCalendar.PRIV_KEY_SECRET);
var privateKey = certificate.Export(X509ContentType.Cert);
return JsonWebToken.Encode(payload, privateKey, JwtHashAlgorithm.RS256);
}
}
I don't understand why I have a FileLoadException on the System.Threading.Tasks assembly. I try to add a new functionality to an application which already use Tasks without problems. This app uses TabPage objects which run in different threads.
Answer
Remove all references to System.Threading.Tasks and then add in the one from whatever .NET version you are using (.NET 4.0).
The Google Calendar API might be using a different version of .NET
You can specify which version of the assembly to use in your app.config
<dependentAssembly>
<assemblyIdentity name="someAssembly"
publicKeyToken="32ab4ba45e0a69a1"
culture="en-us" />
<bindingRedirect oldVersion="7.0.0.0" newVersion="8.0.0.0" />
</dependentAssembly>