public IEnumerable <ModelValidationResult> Validate(ModelValidationContext context)
{
if (NotAllowed.Contains(context.Model as string))
{
return(new List <ModelValidationResult> {
new ModelValidationResult("", ErrorMessage)
});
}
else
{
return(Enumerable.Empty <ModelValidationResult>());
}
}
public string ShortenWithCustomHash(string url, string customHash)
{
if (String.IsNullOrWhiteSpace(customHash))
{
throw new ArgumentException("The custom short URL cannot be empty.");
}
if (customHash.Length > 100)
{
throw new ArgumentException("The custom short URL must be no longer than 100 characters.");
}
var unreserved = new Regex(@"[a-z]|[A-Z]|[0-9]|\-|\.|_|\~");
if (customHash.EndsWith(".") || !customHash.All(c => unreserved.IsMatch(c.ToString())))
{
throw new ArgumentException(
"The custom short URL must only contain letters A ... Z, numbers 0 ... 9 or " +
"dash (-), underscore (_), dot(.), or tilde (~)");
}
if (NotAllowed.Contains(customHash))
{
throw new ArgumentException("That custom short URL is not available.");
}
var directUrl = UrlUnwrapper.GetDirectUrl(url);
if (Repository.ContainsKey(customHash))
{
throw new ArgumentException("The given custom short URL is already in use.");
}
if (Repository.ContainsValue(directUrl))
{
var oldKey = Repository.GetKey(directUrl);
Repository.Remove(oldKey);
}
Repository.Add(customHash, directUrl);
return(CompleteUrl(customHash));
}