src/log4net/Layout/XmlLayout.cs - logging-log4net - Git at Google

 #region Apache License
 //
 // Licensed to the Apache Software Foundation (ASF) under one or more
 // contributor license agreements. See the NOTICE file distributed with
 // this work for additional information regarding copyright ownership.
 // The ASF licenses this file to you under the Apache License, Version 2.0
 // (the "License"); you may not use this file except in compliance with
 // the License. You may obtain a copy of the License at
 //
 // http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 //
 #endregion

 using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Xml;

 using log4net.Core;
 using log4net.Layout.Internal;
 using log4net.Util;

 namespace log4net.Layout
 {
   /// <summary>
   /// Layout that formats the log events as XML elements.
   /// </summary>
   /// <remarks>
   /// <para>
   /// The output of the <see cref="XmlLayout" /> consists of a series of
   /// log4net:event elements. It does not output a complete well-formed XML
   /// file. The output is designed to be included as an <em>external entity</em>
   /// in a separate file to form a correct XML file.
   /// </para>
   /// <para>
   /// For example, if <c>abc</c> is the name of the file where
   /// the <see cref="XmlLayout" /> output goes, then a well-formed XML file would
   /// be:
   /// </para>
   /// <code lang="XML">
   /// &lt;?xml version="1.0" ?&gt;
   ///
   /// &lt;!DOCTYPE log4net:events SYSTEM "log4net-events.dtd" [&lt;!ENTITY data SYSTEM "abc"&gt;]&gt;
   ///
   /// &lt;log4net:events version="1.2" xmlns:log4net="http://logging.apache.org/log4net/schemas/log4net-events-1.2&gt;
   ///     &amp;data;
   /// &lt;/log4net:events&gt;
   /// </code>
   /// <para>
   /// This approach enforces the independence of the <see cref="XmlLayout" />
   /// and the appender where it is embedded.
   /// </para>
   /// <para>
   /// The <c>version</c> attribute helps components to correctly
   /// interpret output generated by <see cref="XmlLayout" />. The value of
   /// this attribute should be "1.2" for release 1.2 and later.
   /// </para>
   /// <para>
   /// Alternatively the <c>Header</c> and <c>Footer</c> properties can be
   /// configured to output the correct XML header, open tag and close tag.
   /// When setting the <c>Header</c> and <c>Footer</c> properties it is essential
   /// that the underlying data store not be appendable otherwise the data
   /// will become invalid XML.
   /// </para>
   /// </remarks>
   /// <author>Nicko Cadell</author>
   /// <author>Gert Driesen</author>
   public class XmlLayout : XmlLayoutBase
   {
     /// <summary>
     /// Constructs an XmlLayout
     /// </summary>
     public XmlLayout()
     {
     }

     /// <summary>
     /// Constructs an XmlLayout.
     /// </summary>
     /// <remarks>
     /// <para>
     /// The <b>LocationInfo</b> option takes a boolean value. By
     /// default, it is set to false which means there will be no location
     /// information output by this layout. If the option is set to
     /// true, then the file name and line number of the statement
     /// at the origin of the log statement will be output.
     /// </para>
     /// <para>
     /// If you are embedding this layout within an SmtpAppender
     /// then make sure to set the <b>LocationInfo</b> option of that
     /// appender as well.
     /// </para>
     /// </remarks>
     public XmlLayout(bool locationInfo) : base(locationInfo)
     {
     }

     /// <summary>
     /// The prefix to use for all element names
     /// </summary>
     /// <remarks>
     /// <para>
     /// The default prefix is <b>log4net</b>. Set this property
     /// to change the prefix. If the prefix is set to an empty string
     /// then no prefix will be written.
     /// </para>
     /// </remarks>
     public string Prefix { get; set; } = PREFIX;

     /// <summary>
     /// Set whether to base64 encode the message.
     /// </summary>
     /// <remarks>
     /// <para>
     /// By default the log message will be written as text to the xml
     /// output. This can cause problems when the message contains binary
     /// data. By setting this to true the contents of the message will be
     /// base64 encoded. If this is set then invalid character replacement
     /// (see <see cref="XmlLayoutBase.InvalidCharReplacement"/>) will not be performed
     /// on the log message.
     /// </para>
     /// </remarks>
     public bool Base64EncodeMessage { get; set; }

     /// <summary>
     /// Set whether to base64 encode the property values.
     /// </summary>
     /// <remarks>
     /// <para>
     /// By default the properties will be written as text to the xml
     /// output. This can cause problems when one or more properties contain
     /// binary data. By setting this to true the values of the properties
     /// will be base64 encoded. If this is set then invalid character replacement
     /// (see <see cref="XmlLayoutBase.InvalidCharReplacement"/>) will not be performed
     /// on the property values.
     /// </para>
     /// </remarks>
     public bool Base64EncodeProperties { get; set; }

     /// <summary>
     /// Initialize layout options
     /// </summary>
     /// <remarks>
     /// <para>
     /// This is part of the <see cref="IOptionHandler"/> delayed object
     /// activation scheme. The <see cref="ActivateOptions"/> method must
     /// be called on this object after the configuration properties have
     /// been set. Until <see cref="ActivateOptions"/> is called this
     /// object is in an undefined state and must not be used.
     /// </para>
     /// <para>
     /// If any of the configuration properties are modified then
     /// <see cref="ActivateOptions"/> must be called again.
     /// </para>
     /// <para>
     /// Builds a cache of the element names
     /// </para>
     /// </remarks>
     public override void ActivateOptions()
     {
       base.ActivateOptions();

       // Cache the full element names including the prefix
       if (Prefix.Length > 0)
       {
         m_elmEvent = Prefix + ":" + ELM_EVENT;
         m_elmMessage = Prefix + ":" + ELM_MESSAGE;
         m_elmProperties = Prefix + ":" + ELM_PROPERTIES;
         m_elmData = Prefix + ":" + ELM_DATA;
         m_elmException = Prefix + ":" + ELM_EXCEPTION;
         m_elmLocation = Prefix + ":" + ELM_LOCATION;
       }
     }

     /// <summary>
     /// Does the actual writing of the XML.
     /// </summary>
     /// <param name="writer">The writer to use to output the event to.</param>
     /// <param name="loggingEvent">The event to write.</param>
     /// <remarks>
     /// <para>
     /// Override the base class <see cref="XmlLayoutBase.FormatXml"/> method
     /// to write the <see cref="LoggingEvent"/> to the <see cref="XmlWriter"/>.
     /// </para>
     /// </remarks>
     protected override void FormatXml(XmlWriter writer, LoggingEvent loggingEvent)
     {
       writer.WriteStartElement(m_elmEvent, Prefix, ELM_EVENT, Prefix);
       writer.WriteAttributeString(ATTR_LOGGER, loggingEvent.LoggerName!);

       writer.WriteAttributeString(ATTR_TIMESTAMP, XmlConvert.ToString(loggingEvent.TimeStamp, XmlDateTimeSerializationMode.Local));

       writer.WriteAttributeString(ATTR_LEVEL, loggingEvent.Level.DisplayName);
       writer.WriteAttributeString(ATTR_THREAD, loggingEvent.ThreadName!);

       if (loggingEvent.Domain != null && loggingEvent.Domain.Length > 0)
       {
         writer.WriteAttributeString(ATTR_DOMAIN, loggingEvent.Domain);
       }
       if (loggingEvent.Identity != null && loggingEvent.Identity.Length > 0)
       {
         writer.WriteAttributeString(ATTR_IDENTITY, loggingEvent.Identity);
       }
       if (loggingEvent.UserName.Length > 0)
       {
         writer.WriteAttributeString(ATTR_USERNAME, loggingEvent.UserName);
       }

       // Append the message text
       writer.WriteStartElement(m_elmMessage, Prefix, ELM_MESSAGE, Prefix);
       if (!Base64EncodeMessage)
       {
         Transform.WriteEscapedXmlString(writer, loggingEvent.RenderedMessage, this.InvalidCharReplacement);
       }
       else
       {
         byte[] messageBytes = Encoding.UTF8.GetBytes(loggingEvent.RenderedMessage);
         string base64Message = Convert.ToBase64String(messageBytes, 0, messageBytes.Length);
         Transform.WriteEscapedXmlString(writer, base64Message, this.InvalidCharReplacement);
       }
       writer.WriteEndElement();

       PropertiesDictionary properties = loggingEvent.GetProperties();

       // Append the properties text
       if (properties.Count > 0)
       {
         writer.WriteStartElement(m_elmProperties, Prefix, ELM_PROPERTIES, Prefix);
         foreach (KeyValuePair<string, object?> entry in properties)
         {
           writer.WriteStartElement(m_elmData, Prefix, ELM_DATA, Prefix);
           writer.WriteAttributeString(ATTR_NAME, Transform.MaskXmlInvalidCharacters(entry.Key, InvalidCharReplacement));

           // Use an ObjectRenderer to convert the object to a string
           string valueStr;
           if (!Base64EncodeProperties)
           {
             valueStr = Transform.MaskXmlInvalidCharacters(loggingEvent.Repository.RendererMap.FindAndRender(entry.Value), InvalidCharReplacement);
           }
           else
           {
             byte[] propertyValueBytes = Encoding.UTF8.GetBytes(loggingEvent.Repository.RendererMap.FindAndRender(entry.Value));
             valueStr = Convert.ToBase64String(propertyValueBytes, 0, propertyValueBytes.Length);
           }
           writer.WriteAttributeString(ATTR_VALUE, valueStr);

           writer.WriteEndElement();
         }
         writer.WriteEndElement();
       }

       string exceptionStr = loggingEvent.GetExceptionString();
       if (exceptionStr != null && exceptionStr.Length > 0)
       {
         // Append the stack trace line
         writer.WriteStartElement(m_elmException, Prefix, ELM_EXCEPTION, Prefix);
         Transform.WriteEscapedXmlString(writer, exceptionStr, InvalidCharReplacement);
         writer.WriteEndElement();
       }

       if (LocationInfo)
       {
         LocationInfo locationInfo = loggingEvent.LocationInformation;

         writer.WriteStartElement(m_elmLocation, Prefix, ELM_LOCATION, Prefix);
         writer.WriteAttributeString(ATTR_CLASS, locationInfo.ClassName);
         writer.WriteAttributeString(ATTR_METHOD, locationInfo.MethodName);
         writer.WriteAttributeString(ATTR_FILE, locationInfo.FileName);
         writer.WriteAttributeString(ATTR_LINE, locationInfo.LineNumber);
         writer.WriteEndElement();
       }

       writer.WriteEndElement();
     }

     private string m_elmEvent = ELM_EVENT;
     private string m_elmMessage = ELM_MESSAGE;
     private string m_elmData = ELM_DATA;
     private string m_elmProperties = ELM_PROPERTIES;
     private string m_elmException = ELM_EXCEPTION;
     private string m_elmLocation = ELM_LOCATION;

     private const string PREFIX = "log4net";

     private const string ELM_EVENT = "event";
     private const string ELM_MESSAGE = "message";
     private const string ELM_PROPERTIES = "properties";
     private const string ELM_DATA = "data";
     private const string ELM_EXCEPTION = "exception";
     private const string ELM_LOCATION = "locationInfo";

     private const string ATTR_LOGGER = "logger";
     private const string ATTR_TIMESTAMP = "timestamp";
     private const string ATTR_LEVEL = "level";
     private const string ATTR_THREAD = "thread";
     private const string ATTR_DOMAIN = "domain";
     private const string ATTR_IDENTITY = "identity";
     private const string ATTR_USERNAME = "username";
     private const string ATTR_CLASS = "class";
     private const string ATTR_METHOD = "method";
     private const string ATTR_FILE = "file";
     private const string ATTR_LINE = "line";
     private const string ATTR_NAME = "name";
     private const string ATTR_VALUE = "value";
   }
 }
	#region Apache License
	//
	// Licensed to the Apache Software Foundation (ASF) under one or more
	// contributor license agreements. See the NOTICE file distributed with
	// this work for additional information regarding copyright ownership.
	// The ASF licenses this file to you under the Apache License, Version 2.0
	// (the "License"); you may not use this file except in compliance with
	// the License. You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.
	//
	#endregion

	using System;
	using System.Collections.Generic;
	using System.Text;
	using System.Xml;

	using log4net.Core;
	using log4net.Layout.Internal;
	using log4net.Util;

	namespace log4net.Layout
	{
	/// <summary>
	/// Layout that formats the log events as XML elements.
	/// </summary>
	/// <remarks>
	/// <para>
	/// The output of the <see cref="XmlLayout" /> consists of a series of
	/// log4net:event elements. It does not output a complete well-formed XML
	/// file. The output is designed to be included as an <em>external entity</em>
	/// in a separate file to form a correct XML file.
	/// </para>
	/// <para>
	/// For example, if <c>abc</c> is the name of the file where
	/// the <see cref="XmlLayout" /> output goes, then a well-formed XML file would
	/// be:
	/// </para>
	/// <code lang="XML">
	/// <?xml version="1.0" ?>
	///
	/// <!DOCTYPE log4net:events SYSTEM "log4net-events.dtd" [<!ENTITY data SYSTEM "abc">]>
	///
	/// <log4net:events version="1.2" xmlns:log4net="http://logging.apache.org/log4net/schemas/log4net-events-1.2>
	/// &data;
	/// </log4net:events>
	/// </code>
	/// <para>
	/// This approach enforces the independence of the <see cref="XmlLayout" />
	/// and the appender where it is embedded.
	/// </para>
	/// <para>
	/// The <c>version</c> attribute helps components to correctly
	/// interpret output generated by <see cref="XmlLayout" />. The value of
	/// this attribute should be "1.2" for release 1.2 and later.
	/// </para>
	/// <para>
	/// Alternatively the <c>Header</c> and <c>Footer</c> properties can be
	/// configured to output the correct XML header, open tag and close tag.
	/// When setting the <c>Header</c> and <c>Footer</c> properties it is essential
	/// that the underlying data store not be appendable otherwise the data
	/// will become invalid XML.
	/// </para>
	/// </remarks>
	/// <author>Nicko Cadell</author>
	/// <author>Gert Driesen</author>
	public class XmlLayout : XmlLayoutBase
	{
	/// <summary>
	/// Constructs an XmlLayout
	/// </summary>
	public XmlLayout()
	{
	}

	/// <summary>
	/// Constructs an XmlLayout.
	/// </summary>
	/// <remarks>
	/// <para>
	/// The <b>LocationInfo</b> option takes a boolean value. By
	/// default, it is set to false which means there will be no location
	/// information output by this layout. If the option is set to
	/// true, then the file name and line number of the statement
	/// at the origin of the log statement will be output.
	/// </para>
	/// <para>
	/// If you are embedding this layout within an SmtpAppender
	/// then make sure to set the <b>LocationInfo</b> option of that
	/// appender as well.
	/// </para>
	/// </remarks>
	public XmlLayout(bool locationInfo) : base(locationInfo)
	{
	}

	/// <summary>
	/// The prefix to use for all element names
	/// </summary>
	/// <remarks>
	/// <para>
	/// The default prefix is <b>log4net</b>. Set this property
	/// to change the prefix. If the prefix is set to an empty string
	/// then no prefix will be written.
	/// </para>
	/// </remarks>
	public string Prefix { get; set; } = PREFIX;

	/// <summary>
	/// Set whether to base64 encode the message.
	/// </summary>
	/// <remarks>
	/// <para>
	/// By default the log message will be written as text to the xml
	/// output. This can cause problems when the message contains binary
	/// data. By setting this to true the contents of the message will be
	/// base64 encoded. If this is set then invalid character replacement
	/// (see <see cref="XmlLayoutBase.InvalidCharReplacement"/>) will not be performed
	/// on the log message.
	/// </para>
	/// </remarks>
	public bool Base64EncodeMessage { get; set; }

	/// <summary>
	/// Set whether to base64 encode the property values.
	/// </summary>
	/// <remarks>
	/// <para>
	/// By default the properties will be written as text to the xml
	/// output. This can cause problems when one or more properties contain
	/// binary data. By setting this to true the values of the properties
	/// will be base64 encoded. If this is set then invalid character replacement
	/// (see <see cref="XmlLayoutBase.InvalidCharReplacement"/>) will not be performed
	/// on the property values.
	/// </para>
	/// </remarks>
	public bool Base64EncodeProperties { get; set; }

	/// <summary>
	/// Initialize layout options
	/// </summary>
	/// <remarks>
	/// <para>
	/// This is part of the <see cref="IOptionHandler"/> delayed object
	/// activation scheme. The <see cref="ActivateOptions"/> method must
	/// be called on this object after the configuration properties have
	/// been set. Until <see cref="ActivateOptions"/> is called this
	/// object is in an undefined state and must not be used.
	/// </para>
	/// <para>
	/// If any of the configuration properties are modified then
	/// <see cref="ActivateOptions"/> must be called again.
	/// </para>
	/// <para>
	/// Builds a cache of the element names
	/// </para>
	/// </remarks>
	public override void ActivateOptions()
	{
	base.ActivateOptions();

	// Cache the full element names including the prefix
	if (Prefix.Length > 0)
	{
	m_elmEvent = Prefix + ":" + ELM_EVENT;
	m_elmMessage = Prefix + ":" + ELM_MESSAGE;
	m_elmProperties = Prefix + ":" + ELM_PROPERTIES;
	m_elmData = Prefix + ":" + ELM_DATA;
	m_elmException = Prefix + ":" + ELM_EXCEPTION;
	m_elmLocation = Prefix + ":" + ELM_LOCATION;
	}
	}

	/// <summary>
	/// Does the actual writing of the XML.
	/// </summary>
	/// <param name="writer">The writer to use to output the event to.</param>
	/// <param name="loggingEvent">The event to write.</param>
	/// <remarks>
	/// <para>
	/// Override the base class <see cref="XmlLayoutBase.FormatXml"/> method
	/// to write the <see cref="LoggingEvent"/> to the <see cref="XmlWriter"/>.
	/// </para>
	/// </remarks>
	protected override void FormatXml(XmlWriter writer, LoggingEvent loggingEvent)
	{
	writer.WriteStartElement(m_elmEvent, Prefix, ELM_EVENT, Prefix);
	writer.WriteAttributeString(ATTR_LOGGER, loggingEvent.LoggerName!);

	writer.WriteAttributeString(ATTR_TIMESTAMP, XmlConvert.ToString(loggingEvent.TimeStamp, XmlDateTimeSerializationMode.Local));

	writer.WriteAttributeString(ATTR_LEVEL, loggingEvent.Level.DisplayName);
	writer.WriteAttributeString(ATTR_THREAD, loggingEvent.ThreadName!);

	if (loggingEvent.Domain != null && loggingEvent.Domain.Length > 0)
	{
	writer.WriteAttributeString(ATTR_DOMAIN, loggingEvent.Domain);
	}
	if (loggingEvent.Identity != null && loggingEvent.Identity.Length > 0)
	{
	writer.WriteAttributeString(ATTR_IDENTITY, loggingEvent.Identity);
	}
	if (loggingEvent.UserName.Length > 0)
	{
	writer.WriteAttributeString(ATTR_USERNAME, loggingEvent.UserName);
	}

	// Append the message text
	writer.WriteStartElement(m_elmMessage, Prefix, ELM_MESSAGE, Prefix);
	if (!Base64EncodeMessage)
	{
	Transform.WriteEscapedXmlString(writer, loggingEvent.RenderedMessage, this.InvalidCharReplacement);
	}
	else
	{
	byte[] messageBytes = Encoding.UTF8.GetBytes(loggingEvent.RenderedMessage);
	string base64Message = Convert.ToBase64String(messageBytes, 0, messageBytes.Length);
	Transform.WriteEscapedXmlString(writer, base64Message, this.InvalidCharReplacement);
	}
	writer.WriteEndElement();

	PropertiesDictionary properties = loggingEvent.GetProperties();

	// Append the properties text
	if (properties.Count > 0)
	{
	writer.WriteStartElement(m_elmProperties, Prefix, ELM_PROPERTIES, Prefix);
	foreach (KeyValuePair<string, object?> entry in properties)
	{
	writer.WriteStartElement(m_elmData, Prefix, ELM_DATA, Prefix);
	writer.WriteAttributeString(ATTR_NAME, Transform.MaskXmlInvalidCharacters(entry.Key, InvalidCharReplacement));

	// Use an ObjectRenderer to convert the object to a string
	string valueStr;
	if (!Base64EncodeProperties)
	{
	valueStr = Transform.MaskXmlInvalidCharacters(loggingEvent.Repository.RendererMap.FindAndRender(entry.Value), InvalidCharReplacement);
	}
	else
	{
	byte[] propertyValueBytes = Encoding.UTF8.GetBytes(loggingEvent.Repository.RendererMap.FindAndRender(entry.Value));
	valueStr = Convert.ToBase64String(propertyValueBytes, 0, propertyValueBytes.Length);
	}
	writer.WriteAttributeString(ATTR_VALUE, valueStr);

	writer.WriteEndElement();
	}
	writer.WriteEndElement();
	}

	string exceptionStr = loggingEvent.GetExceptionString();
	if (exceptionStr != null && exceptionStr.Length > 0)
	{
	// Append the stack trace line
	writer.WriteStartElement(m_elmException, Prefix, ELM_EXCEPTION, Prefix);
	Transform.WriteEscapedXmlString(writer, exceptionStr, InvalidCharReplacement);
	writer.WriteEndElement();
	}

	if (LocationInfo)
	{
	LocationInfo locationInfo = loggingEvent.LocationInformation;

	writer.WriteStartElement(m_elmLocation, Prefix, ELM_LOCATION, Prefix);
	writer.WriteAttributeString(ATTR_CLASS, locationInfo.ClassName);
	writer.WriteAttributeString(ATTR_METHOD, locationInfo.MethodName);
	writer.WriteAttributeString(ATTR_FILE, locationInfo.FileName);
	writer.WriteAttributeString(ATTR_LINE, locationInfo.LineNumber);
	writer.WriteEndElement();
	}

	writer.WriteEndElement();
	}

	private string m_elmEvent = ELM_EVENT;
	private string m_elmMessage = ELM_MESSAGE;
	private string m_elmData = ELM_DATA;
	private string m_elmProperties = ELM_PROPERTIES;
	private string m_elmException = ELM_EXCEPTION;
	private string m_elmLocation = ELM_LOCATION;

	private const string PREFIX = "log4net";

	private const string ELM_EVENT = "event";
	private const string ELM_MESSAGE = "message";
	private const string ELM_PROPERTIES = "properties";
	private const string ELM_DATA = "data";
	private const string ELM_EXCEPTION = "exception";
	private const string ELM_LOCATION = "locationInfo";

	private const string ATTR_LOGGER = "logger";
	private const string ATTR_TIMESTAMP = "timestamp";
	private const string ATTR_LEVEL = "level";
	private const string ATTR_THREAD = "thread";
	private const string ATTR_DOMAIN = "domain";
	private const string ATTR_IDENTITY = "identity";
	private const string ATTR_USERNAME = "username";
	private const string ATTR_CLASS = "class";
	private const string ATTR_METHOD = "method";
	private const string ATTR_FILE = "file";
	private const string ATTR_LINE = "line";
	private const string ATTR_NAME = "name";
	private const string ATTR_VALUE = "value";
	}
	}