private void WriteCacheData(FileInfo file, DataLogCacheData cacheData)
{
// Create the cache location - Create() will no-op if it already exists
_cacheLocation.Create();
using (FileStream stream = file.Create())
{
// Using a DataContractSerializer instead of HP.ScalableTest.Framework.Serializer
// because it produces about 50% less data and will keep the cache smaller.
_serializer.WriteObject(stream, cacheData);
}
}
/// <summary>
/// Adds the specified log table data to the cache.
/// </summary>
/// <param name="table">The <see cref="LogTableDefinition" />.</param>
/// <param name="record">The <see cref="LogTableRecord" />.</param>
/// <param name="isInsert">if set to <c>true</c> this data should be processed as an insert.</param>
/// <exception cref="ArgumentNullException">
/// <paramref name="table" /> is null.
/// <para>or</para>
/// <paramref name="record" /> is null.
/// </exception>
public void Add(LogTableDefinition table, LogTableRecord record, bool isInsert)
{
if (table == null)
{
throw new ArgumentNullException(nameof(table));
}
if (record == null)
{
throw new ArgumentNullException(nameof(record));
}
string operation = isInsert ? "INSERT" : "UPDATE";
string fileName = $"{table.Name} {operation} {record[table.PrimaryKey]}.xml";
FileInfo file = new FileInfo(Path.Combine(_cacheLocation.FullName, fileName));
LogTrace($"Adding cache file {file.Name}");
DataLogCacheData cacheData = new DataLogCacheData(table, record, isInsert);
WriteCacheData(file, cacheData);
}
public IEnumerable <DataLogDatabaseResult> RetryFromCache()
{
if (!Directory.Exists(_cacheLocation.FullName))
{
return(Enumerable.Empty <DataLogDatabaseResult>());
}
// Ignore files that have exceeded the maximum retry time.
DateTime cutoff = DateTime.Now - _maximumRetryTime;
bool loggedStart = false;
int fileErrors = 0;
List <DataLogDatabaseResult> results = new List <DataLogDatabaseResult>();
foreach (FileInfo file in _cacheLocation.EnumerateFiles("*.xml").Where(n => n.CreationTime > cutoff).OrderBy(n => n.CreationTime))
{
if (!loggedStart)
{
LogDebug("Retrying from cache...");
loggedStart = true;
}
try
{
LogTrace($"Reading cache file {file.Name}");
DataLogCacheData data = ReadCacheData(file);
data.Retries++;
DataLogDatabaseResult result = data.IsInsert ?
_databaseWriter.Insert(data.Table, data.Record) :
_databaseWriter.Update(data.Table, data.Record);
bool operationSuccessful = result.Success;
if (!operationSuccessful && _alternateWriter != null)
{
DataLogDatabaseResult alternateResult = data.IsInsert ?
_alternateWriter.Insert(data.Table, data.Record) :
_alternateWriter.Update(data.Table, data.Record);
operationSuccessful = alternateResult.Success;
}
if (operationSuccessful)
{
LogTrace($"Cache operation successful. Deleting file {file.Name}.");
try
{
Retry.WhileThrowing <IOException>(() => file.Delete(), 5, TimeSpan.FromSeconds(1));
}
catch (IOException ex)
{
LogDebug($"File {file.Name} could not be deleted: {ex.Message}");
}
}
else
{
LogTrace($"Cache operation failed. {file.Name} has been retried {data.Retries} times.");
WriteCacheData(file, data);
}
result.Retries = data.Retries;
results.Add(result);
}
catch (Exception ex)
{
// Do nothing - could be a fluke, or a file that we can't read
LogTrace($"Unknown error: {ex.Message}");
fileErrors++;
}
}
if (results.Any())
{
LogDebug($"Cache retry results: {results.Count(n => n.Success)} succeeded, {results.Count(n => !n.Success)} failed, {fileErrors} cache errors.");
}
return(results);
}