// The Page_Load method fetches the context token and the access token.
// The access token is used by all of the data retrieval methods.
protected void Page_Load(object sender, EventArgs e)
{
string contextTokenString = TokenHelper.GetContextTokenFromRequest(Request);
if(contextTokenString != null)
{
contextToken =
TokenHelper.ReadAndValidateContextToken(
contextTokenString,
Request.Url.Authority);
sharepointUrl = new Uri(Request.QueryString["SPHostUrl"]);
accessToken =
TokenHelper.GetAccessToken(
contextToken,
sharepointUrl.Authority).AccessToken;
// For simplicity, this sample assigns the access token to the buton's CommandArgument property.
// In a production add-in, this would not be secure. The access token should be cached on the server-side.
CSOM.CommandArgument = accessToken;
}
else if (!IsPostBack)
{
Response.Write("Could not find a context token.");
return;
}
}
public SharePointAcsContext(Uri spHostUrl, Uri spAppWebUrl, string spLanguage, string spClientTag, string spProductNumber, string contextToken, SharePointContextToken contextTokenObj)
: base(spHostUrl, spAppWebUrl, spLanguage, spClientTag, spProductNumber)
{
if (string.IsNullOrEmpty(contextToken))
{
throw new ArgumentNullException("contextToken");
}
if (contextTokenObj == null)
{
throw new ArgumentNullException("contextTokenObj");
}
this.contextToken = contextToken;
this.contextTokenObj = contextTokenObj;
}
/// <summary>
/// Retrieves an access token from ACS to call the source of the specified context token at the specified
/// targetHost. The targetHost must be registered for the principal that sent the context token.
/// </summary>
/// <param name="contextToken">Context token issued by the intended access token audience</param>
/// <param name="targetHost">Url authority of the target principal</param>
/// <returns>An access token with an audience matching the context token's source</returns>
public static OAuth2AccessTokenResponse GetAccessToken(SharePointContextToken contextToken, string targetHost)
{
string targetPrincipalName = contextToken.TargetPrincipalName;
// Extract the refreshToken from the context token
string refreshToken = contextToken.RefreshToken;
if (String.IsNullOrEmpty(refreshToken))
{
return null;
}
string targetRealm = Realm ?? contextToken.Realm;
return GetAccessToken(refreshToken,
targetPrincipalName,
targetHost,
targetRealm);
}
