public RedisTokenCache(string signedInUserId)
{
// associate the cache to the current user of the web app
userId = signedInUserId;
this.AfterAccess = AfterAccessNotification;
this.BeforeAccess = BeforeAccessNotification;
this.BeforeWrite = BeforeWriteNotification;
// look up the entry in the cache
var cache = Redis.Connection.GetDatabase();
try
{
var cachedItem = cache.StringGet(userId);
if (cachedItem.HasValue)
{
Cache = JsonConvert.DeserializeObject <UserTokenCacheItem>(cachedItem);
this.Deserialize((Cache == null) ? null : MachineKey.Unprotect(Cache.cacheBits, "ADALCache"));
}
}
catch (Exception ex)
{
Trace.WriteLine("Exception in RedisTokenCache(id): " + ex.Message);
Cache = null;
}
}
// Notification raised before ADAL accesses the cache.
// This is your chance to update the in-memory copy from the cache, if the in-memory version is stale
void BeforeAccessNotification(TokenCacheNotificationArgs args)
{
try
{
var cache = Redis.Connection.GetDatabase();
var cachedItem = cache.StringGet(userId);
if (cachedItem.HasValue)
{
var status = JsonConvert.DeserializeObject <UserTokenCacheItem>(cachedItem);
if ((Cache != null) && (status.LastWrite > Cache.LastWrite))
{
Cache = status;
this.Deserialize((Cache == null) ? null : MachineKey.Unprotect(Cache.cacheBits, "ADALCache"));
}
}
}
catch (Exception ex)
{
Trace.WriteLine("Exception in RedisTokenCache.BeforeAccessNotification: " + ex.Message);
}
}
// Notification raised after ADAL accessed the cache.
// If the HasStateChanged flag is set, ADAL changed the content of the cache
void AfterAccessNotification(TokenCacheNotificationArgs args)
{
// if state changed
if (this.HasStateChanged)
{
Cache = new UserTokenCacheItem
{
cacheBits = MachineKey.Protect(this.Serialize(), "ADALCache"),
LastWrite = DateTime.Now
};
try
{
var cache = Redis.Connection.GetDatabase();
var cacheItemJson = JsonConvert.SerializeObject(Cache);
cache.StringSet(userId, cacheItemJson, TimeSpan.FromDays(1)); // could we use token expiry somehow?
}
catch (Exception ex)
{
Trace.WriteLine("Exception in RedisTokenCache.AfterAccessNotification: " + ex.Message);
}
this.HasStateChanged = false;
}
}
