An Extension to the Enterprise Library Logging Application Block

//===============================================================================
// Microsoft patterns & practices Enterprise Library
// Logging Application Block
//===============================================================================
// Copyright � Microsoft Corporation.  All rights reserved.
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY
// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT
// LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
// FITNESS FOR A PARTICULAR PURPOSE.
//===============================================================================

using System;
using System.Configuration;
using System.Diagnostics;
using Microsoft.Practices.EnterpriseLibrary.Common.Configuration;
using Microsoft.Practices.EnterpriseLibrary.Common.Configuration.ObjectBuilder;
using Data = Microsoft.Practices.EnterpriseLibrary.Data;
using Microsoft.Practices.EnterpriseLibrary.Logging.Formatters;
using Microsoft.Practices.EnterpriseLibrary.Logging.TraceListeners;
using Microsoft.Practices.EnterpriseLibrary.Logging.Configuration;
using Microsoft.Practices.ObjectBuilder;

namespace Microsoft.Practices.EnterpriseLibrary.Logging.Database.Configuration
{
	/// <summary>
	/// Configuration object for a <see cref="FormattedDatabaseTraceListener"/>.
	/// </summary>
	[Assembler(typeof(FormattedDatabaseTraceListenerAssembler))]
	public class FormattedDatabaseTraceListenerData : TraceListenerData
	{
		private const string writeLogStoredProcNameProperty = "writeLogStoredProcName";
		private const string addCategoryStoredProcNameProperty = "addCategoryStoredProcName";
		private const string databaseInstanceNameProperty = "databaseInstanceName";
		private const string formatterNameProperty = "formatter";

		/// <summary>
		/// Initializes a <see cref="FormattedDatabaseTraceListenerData"/>.
		/// </summary>
		public FormattedDatabaseTraceListenerData()
		{
		}

		/// <summary>
		/// Initializes a named instance of <see cref="FormattedDatabaseTraceListenerData"/> with 
		/// name, stored procedure name, databse instance name, and formatter name.
		/// </summary>
		/// <param name="name">The name.</param>
		/// <param name="writeLogStoredProcName">The stored procedure name for writing the log.</param>
		/// <param name="addCategoryStoredProcName">The stored procedure name for adding a category for this log.</param>
		/// <param name="databaseInstanceName">The database instance name.</param>
		/// <param name="formatterName">The formatter name.</param>        
		public FormattedDatabaseTraceListenerData(string name, string writeLogStoredProcName, string addCategoryStoredProcName, 
						string databaseInstanceName, string formatterName)
			: this(name, writeLogStoredProcName, addCategoryStoredProcName, databaseInstanceName, formatterName, TraceOptions.None)
		{
		}

		/// <summary>
		/// Initializes a named instance of <see cref="FormattedDatabaseTraceListenerData"/> with 
		/// name, stored procedure name, databse instance name, and formatter name.
		/// </summary>
		/// <param name="name">The name.</param>
		/// <param name="writeLogStoredProcName">The stored procedure name for writing the log.</param>
		/// <param name="addCategoryStoredProcName">The stored procedure name for adding a category for this log.</param>
		/// <param name="databaseInstanceName">The database instance name.</param>
		/// <param name="formatterName">The formatter name.</param>
		/// <param name="traceOutputOptions">The trace options.</param>
		public FormattedDatabaseTraceListenerData(string name, string writeLogStoredProcName, string addCategoryStoredProcName, 
						string databaseInstanceName, string formatterName, TraceOptions traceOutputOptions)
			: base(name, typeof(FormattedDatabaseTraceListener), traceOutputOptions)
		{
			this.DatabaseInstanceName = databaseInstanceName;
			this.WriteLogStoredProcName = writeLogStoredProcName;
			this.AddCategoryStoredProcName = addCategoryStoredProcName;
			this.Formatter = formatterName;
		}

		/// <summary>
		/// Gets and sets the database instance name.
		/// </summary>
		[ConfigurationProperty(databaseInstanceNameProperty, IsRequired = false)]
		public string DatabaseInstanceName
		{
			get { return (string)base[databaseInstanceNameProperty]; }
			set { base[databaseInstanceNameProperty] = value; }
		}

		/// <summary>
		/// Gets and sets the stored procedure name for writing the log.
		/// </summary>
		[ConfigurationProperty(writeLogStoredProcNameProperty, IsRequired = true)]
		public string WriteLogStoredProcName
		{
			get { return (string)base[writeLogStoredProcNameProperty]; }
			set { base[writeLogStoredProcNameProperty] = value; }
		}

		/// <summary>
		/// Gets and sets the stored procedure name for adding a category for this log.
		/// </summary>
		[ConfigurationProperty(addCategoryStoredProcNameProperty, IsRequired = true)]
		public string AddCategoryStoredProcName
		{
			get { return (string)base[addCategoryStoredProcNameProperty]; }
			set { base[addCategoryStoredProcNameProperty] = value; }
		}

		/// <summary>
		/// Gets and sets the formatter name.
		/// </summary>
		[ConfigurationProperty(formatterNameProperty, IsRequired = false)]
		public string Formatter
		{
			get { return (string)base[formatterNameProperty]; }
			set { base[formatterNameProperty] = value; }
		}
	}

	/// <summary>
	/// This type supports the Enterprise Library infrastructure and is not intended to be used directly from your code.
	/// Represents the process to build a <see cref="FormattedDatabaseTraceListener"/> described by a <see cref="FormattedDatabaseTraceListenerData"/> configuration object.
	/// </summary>
	/// <remarks>This type is linked to the <see cref="FormattedDatabaseTraceListenerData"/> type and it is used by the <see cref="TraceListenerCustomFactory"/> 
	/// to build the specific <see cref="TraceListener"/> object represented by the configuration object.
	/// </remarks>
	public class FormattedDatabaseTraceListenerAssembler : TraceListenerAsssembler
	{
		/// <summary>
		/// This method supports the Enterprise Library infrastructure and is not intended to be used directly from your code.
		/// Builds a <see cref="FormattedDatabaseTraceListener"/> based on an instance of <see cref="FormattedDatabaseTraceListenerData"/>.
		/// </summary>
		/// <seealso cref="TraceListenerCustomFactory"/>
		/// <param name="context">The <see cref="IBuilderContext"/> that represents the current building process.</param>
		/// <param name="objectConfiguration">The configuration object that describes the object to build. Must be an instance of <see cref="FormattedDatabaseTraceListenerData"/>.</param>
		/// <param name="configurationSource">The source for configuration objects.</param>
		/// <param name="reflectionCache">The cache to use retrieving reflection information.</param>
		/// <returns>A fully initialized instance of <see cref="FormattedDatabaseTraceListener"/>.</returns>
		public override TraceListener Assemble(IBuilderContext context, TraceListenerData objectConfiguration, IConfigurationSource configurationSource, ConfigurationReflectionCache reflectionCache)
		{
			FormattedDatabaseTraceListenerData castedObjectConfiguration
				= (FormattedDatabaseTraceListenerData)objectConfiguration;

			Data.Database database =
				(Data.Database)context.HeadOfChain.BuildUp(context, typeof(Data.Database), null, castedObjectConfiguration.DatabaseInstanceName);
			ILogFormatter formatter 
				= LogFormatterCustomFactory.Instance.Create(context, castedObjectConfiguration.Formatter, configurationSource, reflectionCache);

			TraceListener createdObject
				= new FormattedDatabaseTraceListener(
					database,
					castedObjectConfiguration.WriteLogStoredProcName,
					castedObjectConfiguration.AddCategoryStoredProcName,
					formatter);

			return createdObject;
		}
	}
}