//
// Copyright (c) 2004-2006 Jaroslaw Kowalski <jaak@jkowalski.net>
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
//
// * Neither the name of Jaroslaw Kowalski nor the names of its
// contributors may be used to endorse or promote products derived from this
// software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
// THE POSSIBILITY OF SUCH DAMAGE.
//
using System;
using System.Text;
using System.IO;
using NLog.Internal;
using System.ComponentModel;
using NLog.Config;
namespace NLog.LayoutRenderers
{
/// <summary>
/// Contents of the specified file.
/// </summary>
[LayoutRenderer("file-contents")]
public class FileContentsLayoutRenderer: LayoutRenderer
{
private Layout _fileName;
private System.Text.Encoding _encoding = System.Text.Encoding.Default;
private string _lastFileName = "";
private string _fileContents;
/// <summary>
/// Returns the estimated number of characters that are needed to
/// hold the rendered value for the specified logging event.
/// </summary>
/// <param name="logEvent">Logging event information.</param>
/// <returns>The number of characters.</returns>
/// <remarks>
/// If the exact number is not known or
/// expensive to calculate this function should return a rough estimate
/// that's big enough in most cases, but not too big, in order to conserve memory.
/// </remarks>
protected internal override int GetEstimatedBufferSize(LogEventInfo logEvent)
{
return 8;
}
/// <summary>
/// Name of the file.
/// </summary>
[DefaultParameter]
public Layout FileName
{
get { return _fileName; }
set { _fileName = value; }
}
/// <summary>
/// File encoding.
/// </summary>
/// <value>The encoding.</value>
public string Encoding
{
get { return _encoding.WebName; }
set { _encoding = System.Text.Encoding.GetEncoding(value); }
}
/// <summary>
/// Renders the contents of the specified file and appends it to the specified <see cref="StringBuilder" />.
/// </summary>
/// <param name="builder">The <see cref="StringBuilder"/> to append the rendered data to.</param>
/// <param name="logEvent">Logging event.</param>
protected internal override void Append(StringBuilder builder, LogEventInfo logEvent)
{
lock (this)
{
string fileName = _fileName.GetFormattedMessage(logEvent);
if (fileName != _lastFileName)
{
ReadFileContents(fileName);
_lastFileName = fileName;
}
}
builder.Append(_fileContents);
}
private void ReadFileContents(string fileName)
{
_fileContents = "";
try
{
using (StreamReader sr = new StreamReader(fileName, _encoding))
{
_fileContents = sr.ReadToEnd();
}
}
catch (Exception ex)
{
InternalLogger.Warn("Cannot read file {0}: {1}", FileName, ex);
}
}
}
}