/// <summary>
/// Gets a SharePointContext instance associated with the specified HTTP context.
/// </summary>
/// <param name="httpContext">The HTTP context.</param>
/// <returns>The SharePointContext instance. Returns <c>null</c> if not found and a new instance can't be created.</returns>
public SharePointContext GetSharePointContext(HttpContext httpContext)
{
if (httpContext == null)
{
throw new ArgumentNullException(nameof(httpContext));
}
Uri spHostUrl = SharePointContext.GetUriFromQueryStringParameter(httpContext.Request, SharePointContext.SPHostUrlKey);
if (spHostUrl == null)
{
return(null);
}
SharePointContext spContext = LoadSharePointContext(httpContext);
if (spContext == null || !ValidateSharePointContext(spContext, httpContext))
{
spContext = CreateSharePointContext(httpContext.Request);
if (spContext != null)
{
SaveSharePointContext(spContext, httpContext);
}
}
return(spContext);
}
/// <summary>
/// Creates a SharePointContext instance with the specified HTTP request.
/// </summary>
/// <param name="httpRequest">The HTTP request.</param>
/// <returns>The SharePointContext instance. Returns <c>null</c> if errors occur.</returns>
public SharePointContext CreateSharePointContext(HttpRequest httpRequest)
{
if (httpRequest == null)
{
throw new ArgumentNullException(nameof(httpRequest));
}
// SPHostUrl
Uri spHostUrl = SharePointContext.GetUriFromQueryStringParameter(httpRequest, SharePointContext.SPHostUrlKey);
if (spHostUrl == null)
{
return(null);
}
// SPAppWebUrl
Uri spAppWebUrl = SharePointContext.GetUriFromQueryStringParameter(httpRequest, SharePointContext.SPAppWebUrlKey);
if (spAppWebUrl == null)
{
spAppWebUrl = null;
}
// SPLanguage
string spLanguage = httpRequest.Query[SharePointContext.SPLanguageKey];
if (string.IsNullOrEmpty(spLanguage))
{
return(null);
}
// SPClientTag
string spClientTag = httpRequest.Query[SharePointContext.SPClientTagKey];
if (string.IsNullOrEmpty(spClientTag))
{
return(null);
}
// SPProductNumber
string spProductNumber = httpRequest.Query[SharePointContext.SPProductNumberKey];
if (string.IsNullOrEmpty(spProductNumber))
{
return(null);
}
return(CreateSharePointContext(spHostUrl, spAppWebUrl, spLanguage, spClientTag, spProductNumber, httpRequest));
}
protected override bool ValidateSharePointContext(SharePointContext spContext, HttpContext httpContext)
{
SharePointAcsContext spAcsContext = spContext as SharePointAcsContext;
//Checks for the SPCacheKey cookie and gets the value
if (spAcsContext != null)
{
Uri spHostUrl = SharePointContext.GetUriFromQueryStringParameter
(httpContext.Request, SharePointContext.SPHostUrlKey);
string contextToken = TokenHandler.GetContextTokenFromRequest(httpContext.Request);
//read the cookie value
HttpCookie spCacheKeyCookie = new HttpCookie(SPCacheKeyKey, httpContext.Request.Cookies[SPCacheKeyKey]);
string spCacheKey = spCacheKeyCookie != null ? spCacheKeyCookie.Value : null;
return(spHostUrl == spAcsContext.SPHostUrl &&
!string.IsNullOrEmpty(spAcsContext.CacheKey) &&
spCacheKey == spAcsContext.CacheKey &&
!string.IsNullOrEmpty(spAcsContext.ContextToken) &&
(string.IsNullOrEmpty(contextToken) || contextToken == spAcsContext.ContextToken));
}
return(false);
}
/// <summary>
/// Checks if it is necessary to redirect to SharePoint for user to authenticate.
/// </summary>
/// <param name="httpContext">The HTTP context.</param>
/// <param name="redirectUrl">The redirect url to SharePoint if the status is ShouldRedirect. <c>Null</c> if the status is Ok or CanNotRedirect.</param>
/// <returns>Redirection status.</returns>
public static RedirectionStatus CheckRedirectionStatus(HttpContext httpContext, out Uri redirectUrl)
{
if (httpContext == null)
{
throw new ArgumentNullException(nameof(httpContext));
}
redirectUrl = null;
bool contextTokenExpired = false;
try
{
if (Current.GetSharePointContext(httpContext) != null)
{
return(RedirectionStatus.Ok);
}
}
catch (SecurityTokenExpiredException)
{
contextTokenExpired = true;
}
const string SPHasRedirectedToSharePointKey = "SPHasRedirectedToSharePoint";
if (!string.IsNullOrEmpty(httpContext.Request.Query[SPHasRedirectedToSharePointKey]) && !contextTokenExpired)
{
return(RedirectionStatus.CanNotRedirect);
}
Uri spHostUrl = SharePointContext.GetUriFromQueryStringParameter
(httpContext.Request, SharePointContext.SPHostUrlKey);
if (spHostUrl == null)
{
return(RedirectionStatus.CanNotRedirect);
}
if (StringComparer.OrdinalIgnoreCase.Equals(httpContext.Request.Method, "POST"))
{
return(RedirectionStatus.CanNotRedirect);
}
var uri = GetCurrentUrl(httpContext);
var queryNameValueCollection = Microsoft.AspNetCore.WebUtilities.QueryHelpers.ParseQuery(uri);
// Removes the values that are included in {StandardTokens}, as {StandardTokens} will be inserted at the beginning of the query string.
queryNameValueCollection.Remove(SharePointContext.SPHostUrlKey);
queryNameValueCollection.Remove(SharePointContext.SPAppWebUrlKey);
queryNameValueCollection.Remove(SharePointContext.SPLanguageKey);
queryNameValueCollection.Remove(SharePointContext.SPClientTagKey);
queryNameValueCollection.Remove(SharePointContext.SPProductNumberKey);
// Adds SPHasRedirectedToSharePoint=1.
queryNameValueCollection.Add(SPHasRedirectedToSharePointKey, "1");
UriBuilder returnUrlBuilder = new UriBuilder(uri);
returnUrlBuilder.Query = queryNameValueCollection.ToString();
// Inserts StandardTokens.
const string StandardTokens = "{StandardTokens}";
string returnUrlString = returnUrlBuilder.Uri.AbsoluteUri;
returnUrlString = returnUrlString.Insert(returnUrlString.IndexOf("?") + 1, StandardTokens + "&");
// Constructs redirect url.
string redirectUrlString = TokenHandler.GetAppContextTokenRequestUrl(spHostUrl.AbsoluteUri, Uri.EscapeDataString(returnUrlString));
redirectUrl = new Uri(redirectUrlString, UriKind.Absolute);
return(RedirectionStatus.ShouldRedirect);
}
