/// <summary>
/// Checks whether a contact is currently registered with the server
/// </summary>
/// <param name="token">The cancellaion token</param>
/// <param name="e164number">The contact to check.</param>
/// <returns>An optional ContactTokenDetails, present if registered, absent if not.</returns>
public async Task <May <ContactTokenDetails> > GetContact(CancellationToken token, string e164number)// throws IOException
{
string contactToken = CreateDirectoryServerToken(e164number, true);
ContactTokenDetails contactTokenDetails = await PushServiceSocket.GetContactTokenDetails(token, contactToken);
if (contactTokenDetails != null)
{
contactTokenDetails.Number = e164number;
}
return(new May <ContactTokenDetails>(contactTokenDetails));
}