protected override object GetInternal(string key)
{
object value = null;
try
{
if (_directoryValid)
{
//check for a non-expiring cache:
var cachePath = GetFilePath(key);
if (!File.Exists(cachePath))
{
cachePath = null;
//check for expired caches:
var fileName = GetFileNameSearchPattern(key);
var existingCaches = Directory.EnumerateFiles(_directory, fileName).OrderByDescending(x => x);
if (existingCaches.Count() > 0)
{
var mostRecentCache = existingCaches.ElementAt(0);
//if the most recent cache is live, return it -
//format is {key}.cache.{expiresAt}.expiry
if (mostRecentCache.EndsWith(".expiry"))
{
var expiresAt = mostRecentCache.Substring(mostRecentCache.IndexOf(".expiry") - 19, 19);
var expiresAtDate = expiresAt.Replace('-', '/').Replace('_', ':');
var expiryDate = DateTime.Parse(expiresAtDate);
if (expiryDate > DateTime.UtcNow)
{
cachePath = Path.Combine(_directory, mostRecentCache);
}
else
{
var deleteKey = key;
Task.Factory.StartNew(() => DeleteFile(deleteKey));
}
}
}
}
if (cachePath != null)
{
if (CacheConfiguration.Current.DiskCache.EncryptItems)
{
var encryptedBytes = File.ReadAllBytes(cachePath);
value = SimpleAes.Decrypt(encryptedBytes);
}
else
{
value = File.ReadAllText(cachePath);
}
}
}
}
catch (Exception ex)
{
Log.Warn("DiskCache.GetInternal - failed, item not returned. Message: {0}", ex.Message);
}
return(value);
}
public void TestSymetrical()
{
const string original = "this is a test string";
using (var aes = new SimpleAes())
{
var enc = aes.Encrypt(original);
Debug.WriteLine("encrypted = " + enc);
string decrypted = aes.Decrypt(enc);
Assert.AreEqual(original, decrypted);
var secondEnc = aes.Encrypt(original);
Assert.AreNotEqual(secondEnc, enc);
}
}
public string DecryptAESFromBase64String(string cipher)
{
string htmlUnsafeCipher = cipher.Replace('_', '/').Replace('-', '+');
switch (cipher.Length % 4)
{
case 2:
{
htmlUnsafeCipher += "==";
break;
}
case 3:
{
htmlUnsafeCipher += "=";
break;
}
}
var cipherBytes = Convert.FromBase64String(htmlUnsafeCipher);
return(SimpleAes.Decrypt(cipherBytes));
}
public string DecryptAES(byte[] cipherBytes)
{
return(SimpleAes.Decrypt(cipherBytes));
}