public override void OnActionExecuting(HttpActionContext actionContext)
{
if (actionContext == null)
{
throw new ArgumentNullException("actionContext");
}
if (WebAPIHelper.HasCacheEntry(actionContext.ControllerContext))
{
return;
}
else
{
actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.MethodNotAllowed, CoreResources.Services_AccessDenied);
return;
}
}
/// <summary>
/// This method needs to be called from a code behind of the SharePoint app startup page (default.aspx). It registers the calling
/// SharePoint app by calling a specific "Register" api in your WebAPI service.
///
/// Note:
/// Given that method is async you'll need to add the Async="true" page directive to the page that uses this method.
/// </summary>
/// <param name="context">The HttpContextBase object, needed to insert the services token cookie and read the querystring</param>
/// <param name="apiRequest">Route to the "Register" API</param>
/// <param name="serviceEndPoint">Optional Uri to the WebAPI service endpoint. If null then the assumption is taken that the WebAPI is hosted together with the page making this call</param>
public static void RegisterWebAPIService(HttpContextBase context, string apiRequest, Uri serviceEndPoint = null)
{
if (context == null)
{
throw new ArgumentNullException("context");
}
if (string.IsNullOrEmpty(apiRequest))
{
throw new ArgumentNullException("apiRequest");
}
HttpRequestBase request = context.Request;
try
{
if (request.QueryString.AsString(SERVICES_TOKEN, string.Empty).Equals(string.Empty))
{
// Construct a JsonWebSecurityToken so we can fetch the cachekey...implementation is copied from tokenhelper approach
string cacheKey = string.Empty;
string contextToken = TokenHelper.GetContextTokenFromRequest(request);
JsonWebSecurityTokenHandler tokenHandler = TokenHelper.CreateJsonWebSecurityTokenHandler();
SecurityToken securityToken = tokenHandler.ReadToken(contextToken);
JsonWebSecurityToken jsonToken = securityToken as JsonWebSecurityToken;
string appctx = GetClaimValue(jsonToken, "appctx");
if (appctx != null)
{
ClientContext ctx = new ClientContext("http://tempuri.org");
Dictionary <string, object> dict = (Dictionary <string, object>)ctx.ParseObjectFromJsonString(appctx);
cacheKey = (string)dict["CacheKey"];
}
// Remove special chars (=, +, /, {}) from cachekey as there's a flaw in CookieHeaderValue when the
// cookie is read. This flaw replaces special chars with a space.
cacheKey = RemoveSpecialCharacters(cacheKey);
bool httpOnly = true;
if (serviceEndPoint != null)
{
if (!serviceEndPoint.Host.Equals(context.Request.Url.Host, StringComparison.InvariantCultureIgnoreCase))
{
httpOnly = false;
}
}
else
{
serviceEndPoint = new Uri(String.Format("{0}://{1}:{2}", context.Request.Url.Scheme, context.Request.Url.Host, context.Request.Url.Port));
}
// Write the cachekey in a cookie
HttpCookie cookie = new HttpCookie(SERVICES_TOKEN)
{
Value = cacheKey,
Secure = true,
HttpOnly = httpOnly,
};
context.Response.AppendCookie(cookie);
//Register the ClientContext
WebAPIContext sharePointServiceContext = new WebAPIContext()
{
CacheKey = cacheKey,
ClientId = TokenHelper.ClientId,
ClientSecret = TokenHelper.ClientSecret,
Token = contextToken,
HostWebUrl = context.Request.QueryString.AsString("SPHostUrl", null),
AppWebUrl = context.Request.QueryString.AsString("SPAppWebUrl", null),
HostedAppHostName = String.Format("{0}:{1}", context.Request.Url.Host, context.Request.Url.Port),
};
WebAPIHelper.AddToCache(sharePointServiceContext);
}
}
catch (Exception ex)
{
throw new UnauthorizedAccessException("The context token cannot be validated.", ex);
}
}
