protected override async Task WriteCacheBytesAsync(string cacheKey, byte[] bytes)
{
if (_cacheDbRecord == null)
{
_cacheDbRecord = new TokenCacheDbRecord
{
CacheKey = cacheKey
};
}
_cacheDbRecord.CacheBits = _dataProtector.Protect(bytes);
_cacheDbRecord.LastWrite = DateTime.Now;
try
{
// Update the DB and the lastwrite
_tokenCacheDb.Entry(_cacheDbRecord).State = _cacheDbRecord.TokenCacheId == 0 ? EntityState.Added : EntityState.Modified;
_tokenCacheDb.SaveChanges();
}
catch (DbUpdateConcurrencyException)
{
// Record already updated on a different thread, so just read the updated record
await ReadCacheBytesAsync(cacheKey).ConfigureAwait(false);
}
}
protected override async Task <byte[]> ReadCacheBytesAsync(string cacheKey)
{
if (_inMemoryCache == null) // first time access
{
try
{
_inMemoryCache = GetLatestRecordQuery(cacheKey).FirstOrDefault();
}
catch (SqlException ex) when(ex.Message == "Invalid object name 'Records'")
{
// Microsoft.Identity.Web changed from several tables (AppTokenCache, UserTokenCache) to one table (record)
// If you care about the cache, you can migrate them, otherwise re-create the database
throw new Exception("You need to migrate the AppTokenCache and UserTokenCache tables to Records, or run SqlTokenCacheProviderExtension.CreateTokenCachingTablesInSqlDatabase() to create the database", ex);
}
catch (SqlException ex) when(ex.Message.StartsWith("Cannot open database \"MY_TOKEN_CACHE_DATABASE\" requested by the login."))
{
throw new Exception("You need to run SqlTokenCacheProviderExtension.CreateTokenCachingTablesInSqlDatabase() to create the database", ex);
}
}
else
{
// retrieve last written record from the DB
var lastwriteInDb = GetLatestRecordQuery(cacheKey).Select(n => n.LastWrite).FirstOrDefault();
// if the persisted copy is newer than the in-memory copy
if (lastwriteInDb > _inMemoryCache.LastWrite)
{
// read from from storage, update in-memory copy
_inMemoryCache = GetLatestRecordQuery(cacheKey).FirstOrDefault();
}
}
// Send data to the TokenCache instance
return((_inMemoryCache == null) ? null : _dataProtector.Unprotect(_inMemoryCache.CacheBits));
}
protected override Task <byte[]> ReadCacheBytesAsync(string cacheKey)
{
try
{
_cacheDbRecord = GetLatestRecordQuery(cacheKey).FirstOrDefault();
}
catch (SqlException ex) when(ex.Message == "Invalid object name 'Records'")
{
// Microsoft.Identity.Web changed from several tables (AppTokenCache, UserTokenCache) to one table (record)
// If you care about the cache, you can migrate them, otherwise re-create the database
throw new Exception("You need to migrate the AppTokenCache and UserTokenCache tables to Records, or run SqlTokenCacheProviderExtension.CreateTokenCachingTablesInSqlDatabase() to create the database", ex);
}
catch (SqlException ex) when(ex.Message.StartsWith("Cannot open database"))
{
throw new Exception("You need to run SqlTokenCacheProviderExtension.CreateTokenCachingTablesInSqlDatabase() to create the database", ex);
}
// Send data to the TokenCache instance
return(Task.FromResult((_cacheDbRecord == null) ? null : _dataProtector.Unprotect(_cacheDbRecord.CacheBits)));
}