About

This is a fork of the ElmahCore project, with changes for PR's that were sitting idle. It should be an almost slot in replacement for ElmahCore v2.1.2.

See changelog.md for any further changes from v2.1.2

The interfaces and namespaces have been kept the same.

License

This project is licensed under the terms of the Apache license 2.0.

Warnings & Dragons

The source code for the front end appears non-existent, in ElmahCore the front end Vue SPA files are all minified. Consider this a warning sign for the continuation of the front end without a rewrite WITH SOURCE. Source-maps may have enough content to obtain the code but this has not be investigated.

Using ElmahCore

ELMAH for Net.Standard 2.0 and .Net 6

Add NuGet package ElmahCoreEx

Simple usage

// Startup.cs
services.AddElmah() //in ConfigureServices
// ...
app.UseElmah(); // in Configure, must be positioned after initializing other exception handlers
                // such as UseExceptionHandler and UseDeveloperExceptionPage

Default ELMAH endpoint path ~/elmah.

Change URL path

services.AddElmah(options => options.Path = "you_path_here")

Restrict access to the ELMAH URL

services.AddElmah(options =>
{
    options.OnPermissionCheck = context => context.User.Identity.IsAuthenticated;
});

// startup.cs
app.UseAuthentication();
app.UseAuthorization();
//...
app.UseElmah(); // needs to be positioned after `UseAuthentication` and `UseAuthorization`

or the user will be redirected to the sign in screen even if they are authenticated.

Change Error Log type

You can implement a custom error log adapter, to write logs to alternate locations.

public class MyErrorLog: ErrorLog {
    // Implement ErrorLog
}    

The ErrorLog adapters available:

• MemoryErrorLog – store errors in memory (by default)
• XmlFileErrorLog – store errors in XML files.
• SqlErrorLog - store errors in MS SQL (add reference to ElmahCoreEx.Sql)
• MysqlErrorLog - store errors in MySQL (add reference to ElmahCoreEx.MySql)
• PgsqlErrorLog - store errors in PostgreSQL (add reference to ElmahCoreEx.Postgresql)

Example to configure for XML:

services.AddElmah<XmlFileErrorLog>(options =>
{
  options.LogPath = "~/log"; // OR options.LogPath = "с:\errors";
});

Example to configure For MSSQL

services.AddElmah<SqlErrorLog>(options =>
{
  options.ConnectionString = "connection_string";
  options.SqlServerDatabaseSchemaName = "Errors"; // Defaults to dbo if not set
  options.SqlServerDatabaseTableName = "ElmahError"; // Defaults to ELMAH_Error if not set
});

Raise exception

To raise a custom exception to log:

public IActionResult RaiseCustomExceptionExample()
{
    HttpContext.RaiseError(new InvalidOperationException("Test"));
}

Microsoft.Extensions.Logging support

ElmahCoreEx support Microsoft.Extensions.Logging

Source Preview

ElmahCoreEx support source preview. Add paths to source files example:

services.AddElmah(options =>
{
   options.SourcePaths = new []
   {
      @"D:\src\ElmahCore.DemoCore6",
      @"D:\src\ElmahCore.Mvc",
      @"D:\src\ElmahCore"
   };
});

Logging request body

V2.0.5+ ElmahCoreEx can log the request body.

Logging SQL request body

v2.0.6+ ElmahCoreEx can log the SQL request body.

Logging method parameters

V2.0.6+ ElmahCoreEx can log method parameters.

using ElmahCore;
...

public void TestMethod(string p1, int p2)
{
    // Logging method parameters
    this.LogParams((nameof(p1), p1), (nameof(p2), p2));
    ...
}

Using UseElmahExceptionPage

You can replace UseDeveloperExceptionPage to UseElmahExceptionPage

if (env.IsDevelopment())
{
   // app.UseDeveloperExceptionPage();
   app.UseElmahExceptionPage();
}

Using Notifiers

You can create custom notifiers by implementing IErrorNotifier or IErrorNotifierWithId interface and add notifier to Elmah options:

services.AddElmah<XmlFileErrorLog>(options =>
{
    options.Path = @"errors";
    options.LogPath = "~/logs";
    options.Notifiers.Add(new ErrorMailNotifier("Email",emailOptions));
});

Each notifier must have unique name.

Using Filters

You can use Elmah XML filter configuration in a separate file, create and add custom filters:

services.AddElmah<XmlFileErrorLog>(options =>
{
    options.FiltersConfig = "elmah.xml";
    options.Filters.Add(new MyFilter());
})

Custom filter must implement IErrorFilter. An XML filter config example:

<?xml version="1.0" encoding="utf-8" ?>
<elmah>
 <errorFilter>
  <notifiers>
   <notifier name="Email"/>
  </notifiers>
  <test>
   <and>
    <greater binding="HttpStatusCode" value="399" type="Int32" />
    <lesser  binding="HttpStatusCode" value="500" type="Int32" />
   </and>
  </test>
 </errorFilter>
</elmah>

see more here

JavaScript filters have not been implemented

Add notifiers to errorFilter node if you do not want to send notifications Filtered errors will be logged, but will not be sent.