Elmah Error Logging with ASP.NET MVC

Elmah Error Logging with ASP.NET MVC

I’ve pieced this together from a few different articles to give you a one stop shop on how to implement Elmah with your MVC site.

You’ll want to install Elmah through the Package Manager. Use the command Install-Package elmah

First we’ll tackle the config file. To implement just copy and paste into the appropriate sections of your web.config.

<configSections> <sectionGroup name="elmah"> <section name="security" requirePermission="false" type="Elmah.SecuritySectionHandler, Elmah" /> <section name="errorLog" requirePermission="false" type="Elmah.ErrorLogSectionHandler, Elmah" /> <section name="errorMail" requirePermission="false" type="Elmah.ErrorMailSectionHandler, Elmah" /> <section name="errorFilter" requirePermission="false" type="Elmah.ErrorFilterSectionHandler, Elmah" /> </sectionGroup> </configSections>

<appSettings> <add key="elmah.mvc.disableHandler" value="false" /> <add key="elmah.mvc.disableHandleErrorFilter" value="false" /> <add key="elmah.mvc.requiresAuthentication" value="false" /> <add key="elmah.mvc.allowedRoles" value="*" /> <add key="elmah.mvc.route" value="elmah" /> </appSettings>

<system.web> <httpModules> <add name="ErrorLog" type="Elmah.ErrorLogModule, Elmah" /> <add name="ErrorMail" type="Elmah.ErrorMailModule, Elmah" /> <add name="ErrorFilter" type="Elmah.ErrorFilterModule, Elmah" /> </httpModules> <httpHandlers> <add verb="POST,GET,HEAD" path="elmah.axd" type="Elmah.ErrorLogPageFactory, Elmah" /> </httpHandlers> </system.web>

Within the system.webserver section:

<handlers> <add name="Elmah" verb="POST,GET,HEAD" path="elmah.axd" type="Elmah.ErrorLogPageFactory, Elmah" /> </handlers> <modules> <add name="ErrorLog" type="Elmah.ErrorLogModule, Elmah" preCondition="managedHandler" /> <add name="ErrorMail" type="Elmah.ErrorMailModule, Elmah" preCondition="managedHandler" /> <add name="ErrorFilter" type="Elmah.ErrorFilterModule, Elmah" preCondition="managedHandler" /> </modules>

Last but not least, outside of your system.webserver and just before the end configuration tag. This piece will log into a SQL DB of your choice based on a connection string named ElmahLogging.

<elmah> <security allowRemoteAccess="1" /> <errorLog type="Elmah.SqlErrorLog, Elmah" connectionStringName="ElmahLogging" applicationName="MyExcellentApp"/> </elmah>

The SQL Server ddl to run in your logging database:

/* ELMAH - Error Logging Modules and Handlers for ASP.NET Copyright (c) 2004-9 Atif Aziz. All rights reserved. Author(s): Atif Aziz, http://www.raboof.com Phil Haacked, http://haacked.com Licensed 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. */ -- ELMAH DDL script for Microsoft SQL Server 2000 or later. -- $Id: SQLServer.sql 677 2009-09-29 18:02:39Z azizatif $ DECLARE @DBCompatibilityLevel INT DECLARE @DBCompatibilityLevelMajor INT DECLARE @DBCompatibilityLevelMinor INT SELECT @DBCompatibilityLevel = cmptlevel FROM master.dbo.sysdatabases WHERE name = DB_NAME() IF @DBCompatibilityLevel <> 80 BEGIN SELECT @DBCompatibilityLevelMajor = @DBCompatibilityLevel / 10, @DBCompatibilityLevelMinor = @DBCompatibilityLevel % 10 PRINT N' =========================================================================== WARNING! --------------------------------------------------------------------------- This script is designed for Microsoft SQL Server 2000 (8.0) but your database is set up for compatibility with version ' + CAST(@DBCompatibilityLevelMajor AS NVARCHAR(80)) + N'.' + CAST(@DBCompatibilityLevelMinor AS NVARCHAR(80)) + N'. Although the script should work with later versions of Microsoft SQL Server, you can ensure compatibility by executing the following statement: ALTER DATABASE [' + DB_NAME() + N'] SET COMPATIBILITY_LEVEL = 80 If you are hosting ELMAH in the same database as your application database and do not wish to change the compatibility option then you should create a separate database to host ELMAH where you can set the compatibility level more freely. If you continue with the current setup, please report any compatibility issues you encounter over at: http://code.google.com/p/elmah/issues/list =========================================================================== ' END GO /* ------------------------------------------------------------------------ TABLES ------------------------------------------------------------------------ */ CREATE TABLE [dbo].[ELMAH_Error] ( [ErrorId] UNIQUEIDENTIFIER NOT NULL, [Application] NVARCHAR(60) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL, [Host] NVARCHAR(50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL, [Type] NVARCHAR(100) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL, [Source] NVARCHAR(60) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL, [Message] NVARCHAR(500) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL, [User] NVARCHAR(50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL, [StatusCode] INT NOT NULL, [TimeUtc] DATETIME NOT NULL, [Sequence] INT IDENTITY (1, 1) NOT NULL, [AllXml] NTEXT COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL ) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY] GO ALTER TABLE [dbo].[ELMAH_Error] WITH NOCHECK ADD CONSTRAINT [PK_ELMAH_Error] PRIMARY KEY NONCLUSTERED ([ErrorId]) ON [PRIMARY] GO ALTER TABLE [dbo].[ELMAH_Error] ADD CONSTRAINT [DF_ELMAH_Error_ErrorId] DEFAULT (NEWID()) FOR [ErrorId] GO CREATE NONCLUSTERED INDEX [IX_ELMAH_Error_App_Time_Seq] ON [dbo].[ELMAH_Error] ( [Application] ASC, [TimeUtc] DESC, [Sequence] DESC ) ON [PRIMARY] GO /* ------------------------------------------------------------------------ STORED PROCEDURES ------------------------------------------------------------------------ */ SET QUOTED_IDENTIFIER ON GO SET ANSI_NULLS ON GO CREATE PROCEDURE [dbo].[ELMAH_GetErrorXml] ( @Application NVARCHAR(60), @ErrorId UNIQUEIDENTIFIER ) AS SET NOCOUNT ON SELECT [AllXml] FROM [ELMAH_Error] WHERE [ErrorId] = @ErrorId AND [Application] = @Application GO SET QUOTED_IDENTIFIER OFF GO SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO SET ANSI_NULLS ON GO CREATE PROCEDURE [dbo].[ELMAH_GetErrorsXml] ( @Application NVARCHAR(60), @PageIndex INT = 0, @PageSize INT = 15, @TotalCount INT OUTPUT ) AS SET NOCOUNT ON DECLARE @FirstTimeUTC DATETIME DECLARE @FirstSequence INT DECLARE @StartRow INT DECLARE @StartRowIndex INT SELECT @TotalCount = COUNT(1) FROM [ELMAH_Error] WHERE [Application] = @Application -- Get the ID of the first error for the requested page SET @StartRowIndex = @PageIndex * @PageSize + 1 IF @StartRowIndex <= @TotalCount BEGIN SET ROWCOUNT @StartRowIndex SELECT @FirstTimeUTC = [TimeUtc], @FirstSequence = [Sequence] FROM [ELMAH_Error] WHERE [Application] = @Application ORDER BY [TimeUtc] DESC, [Sequence] DESC END ELSE BEGIN SET @PageSize = 0 END -- Now set the row count to the requested page size and get -- all records below it for the pertaining application. SET ROWCOUNT @PageSize SELECT errorId = [ErrorId], application = [Application], host = [Host], type = [Type], source = [Source], message = [Message], [user] = [User], statusCode = [StatusCode], time = CONVERT(VARCHAR(50), [TimeUtc], 126) + 'Z' FROM [ELMAH_Error] error WHERE [Application] = @Application AND [TimeUtc] <= @FirstTimeUTC AND [Sequence] <= @FirstSequence ORDER BY [TimeUtc] DESC, [Sequence] DESC FOR XML AUTO GO SET QUOTED_IDENTIFIER OFF GO SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO SET ANSI_NULLS ON GO CREATE PROCEDURE [dbo].[ELMAH_LogError] ( @ErrorId UNIQUEIDENTIFIER, @Application NVARCHAR(60), @Host NVARCHAR(30), @Type NVARCHAR(100), @Source NVARCHAR(60), @Message NVARCHAR(500), @User NVARCHAR(50), @AllXml NTEXT, @StatusCode INT, @TimeUtc DATETIME ) AS SET NOCOUNT ON INSERT INTO [ELMAH_Error] ( [ErrorId], [Application], [Host], [Type], [Source], [Message], [User], [AllXml], [StatusCode], [TimeUtc] ) VALUES ( @ErrorId, @Application, @Host, @Type, @Source, @Message, @User, @AllXml, @StatusCode, @TimeUtc ) GO SET QUOTED_IDENTIFIER OFF GO SET ANSI_NULLS ON GO

Now that the web.config and database are configured, a few more tweaks to your MVC project and you’re ready to go. By default Elmah will only handle unhandled exceptions. To handle all exceptions that application processes, we can write a custom action filter to intercept the error and log it!

using System.Web.Mvc; using Elmah; namespace MVCproj.ActionFilters { public class ElmahHandledErrorLoggerFilter : IExceptionFilter { public void OnException(ExceptionContext context) { // Log only handled exceptions, because all other will be caught by ELMAH anyway. if (context.ExceptionHandled) ErrorSignal.FromCurrentContext().Raise(context.Exception); } } }

Modify your FilterConfig in the AppStart to look like this:

public class FilterConfig { public static void RegisterGlobalFilters(GlobalFilterCollection filters) { filters.Add(new ElmahHandledErrorLoggerFilter()); filters.Add(new HandleErrorAttribute()); } }

Elmah error logging is now configured for your ASP.NET MVC application. Let’s just hope it doesn’t get used that often. Ha ha… I know bad joke.