/// <summary>
/// Full constructor.
/// </summary>
/// <param name="primaryWriter">The <see cref="ILogWriter"/> instance to first attempt to write to.</param>
/// <param name="secondaryWriter">The <see cref="ILogWriter"/> instance to attempt to write to if the first write attempt fails.</param>
/// <exception cref="System.ArgumentNullException">Thrown if <paramref name="primaryWriter"/> or <paramref name="secondaryWriter"/> is null.</exception>
public FallbackWriter(ILogWriter primaryWriter, ILogWriter secondaryWriter)
{
if (primaryWriter == null)
{
throw new ArgumentNullException(nameof(primaryWriter));
}
if (secondaryWriter == null)
{
throw new ArgumentNullException(nameof(secondaryWriter));
}
var batchWriter = primaryWriter as IBatchLogWriter;
if (batchWriter == null)
{
batchWriter = new BatchLogWriterAdapter(primaryWriter);
}
_PrimaryWriter = batchWriter;
batchWriter = primaryWriter as IBatchLogWriter;
if (batchWriter == null)
{
batchWriter = new BatchLogWriterAdapter(secondaryWriter);
}
_SecondaryWriter = batchWriter;
}
/// <summary>
/// Full constructor.
/// </summary>
/// <param name="logWriter">The log writer to forward events to from the background thread. If multiple output locations are required, usea <see cref="AggregateLogWriter"/> instance.</param>
/// <param name="batchSize">The number of items in the queue before they are actually passed to <paramref name="logWriter"/>.</param>
/// <param name="writeTimeout">The time after the last event was logged to wait before writing items in the queue, even if the queue size is still less than <paramref name="batchSize"/>.</param>
/// <param name="errorHandler">An <see cref="ILoggingErrorHandler"/> implementation used to handle errors that occur.</param>
/// <exception cref="System.ArgumentNullException">Thrown if <paramref name="logWriter"/> is null.</exception>
/// <exception cref="System.ArgumentOutOfRangeException">Thrown if <paramref name="batchSize"/> is less than or equal to zero.</exception>
/// <remarks>
/// <para>If the <paramref name="errorHandler"/> is null then <see cref="SuppressingErrorHandler.DefaultInstance"/> will be used. Ideally the same error handler instance as provided to the parent logger should be used.</para>
/// </remarks>
public AsyncQueueLogWriter(ILogWriter logWriter, int batchSize, TimeSpan writeTimeout, ILoggingErrorHandler errorHandler)
{
#if !CONTRACTS_ONLY
if (logWriter == null)
{
throw new ArgumentNullException(nameof(logWriter));
}
if (batchSize <= 0)
{
throw new ArgumentOutOfRangeException(nameof(batchSize));
}
_ErrorHandler = errorHandler ?? SuppressingErrorHandler.DefaultInstance;
_BatchSize = batchSize;
_WriteTimeout = writeTimeout;
_LogEventPool = new LogEventPool(batchSize * 2);
if (writeTimeout.TotalMilliseconds > 0)
{
_BufferTimeoutTimer = new System.Threading.Timer((reserved) => SetWriteEventsSignal(), null, InfiniteTimespan, InfiniteTimespan);
}
_WriteBufferedEventsSignal = new System.Threading.ManualResetEvent(false);
_BufferedLogEvents = new System.Collections.Concurrent.ConcurrentQueue <PooledObject <LogEvent> >();
var batchedWriter = logWriter as IBatchLogWriter;
if (batchedWriter == null)
{
batchedWriter = new BatchLogWriterAdapter(logWriter);
}
_LogWriter = batchedWriter;
StartBackgroundWriterThread();
#if SUPPORTS_APPDOMAINS
AppDomain.CurrentDomain.DomainUnload += CurrentDomain_DomainUnload;
AppDomain.CurrentDomain.UnhandledException += CurrentDomain_UnhandledException;
AppDomain.CurrentDomain.ProcessExit += CurrentDomain_ProcessExit;
#endif
#endif
}