NLog Database Target for .net Core 2.0

Question

I am trying to write various logs to database and to files using NLog in .net Core 2.0 . The thing is, writing logs to files working perfectly fine. But I always get following error when writing logs to database:

2018-01-10 08:48:29.5666 Error Error initializing target 'Database Target[db]'. Exception: System.TypeLoadException: Could not load type 'System.Data.SqlClient' from assembly 'NLog, Version=4.0.0.0, Culture=neutral, PublicKeyToken=5120e14c03d0593c'. at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMarkHandle stackMark, IntPtr pPrivHostBinder, Boolean loadTypeFromPartialName, ObjectHandleOnStack type, ObjectHandleOnStack keepalive) at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean loadTypeFromPartialName) at System.RuntimeType.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& stackMark) at System.Type.GetType(String typeName, Boolean throwOnError) at NLog.Targets.DatabaseTarget.SetConnectionType() at NLog.Targets.DatabaseTarget.InitializeTarget() at NLog.Targets.Target.Initialize(LoggingConfiguration configuration)

But I have System.Data.SqlClient in my project as follow:

<ItemGroup>
    <PackageReference Include="EPPlus.Core" Version="1.5.4" />
    <PackageReference Include="Microsoft.ApplicationInsights.AspNetCore" Version="2.2.0-beta3" />
    <PackageReference Include="Microsoft.AspNetCore.All" Version="2.0.3" />
    <PackageReference Include="Microsoft.AspNetCore.Authentication.Cookies" Version="2.0.1" />
    <PackageReference Include="Microsoft.AspNetCore.Cors" Version="2.0.1" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="2.0.1" />
    <PackageReference Include="Microsoft.AspNetCore.Session" Version="2.0.1" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="2.0.1" PrivateAssets="All" />
    <PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="2.0.1" PrivateAssets="All" />
    <PackageReference Include="NLog" Version="4.5.0-rc03" />
    <PackageReference Include="NLog.Web.AspNetCore" Version="4.5.0-rc2" />
    <PackageReference Include="System.ComponentModel" Version="4.3.0" />
    <PackageReference Include="System.Configuration.ConfigurationManager" Version="4.5.0-preview1-25914-04" />
    <PackageReference Include="System.Data.SqlClient" Version="4.4.2" />
</ItemGroup>

My NLOG code:

<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" autoReload="true" internalLogLevel="info" internalLogFile="C:\*****\Log2\asdaf.log">
<targets>
    <target
        xsi:type="File"
        name="allfile"
        fileName="C:\*****\Logs\${shortdate}.log"
        layout="${longdate}|${event-properties:item=EventId.Id}|${uppercase:${level}}|${logger}|${message} ${exception}" >
    </target> 

    <target xsi:type="Database" name="db">
        <commandText>INSERT INTO [LogEntries](TimeStamp, Message, Level, Logger) VALUES(getutcdate(), @msg, @level, @logger)</commandText>
        <parameter name="@msg" layout="${message}" />
        <parameter name="@level" layout="${level}" />
        <parameter name="@logger" layout="${logger}" />
        <dbProvider>System.Data.SqlClient</dbProvider>
        <connectionString>*****</connectionString>
    </target>

    <target xsi:type="Null" name="blackhole" />
</targets>
<rules>
    <logger name="*" minlevel="Trace" writeTo="allOutputs" />
    <logger name="Microsoft.*" minlevel="Trace" writeTo="blackhole" final="true" />
    <logger name="*" minlevel="Trace" writeTo="ownFile-web" />
</rules>
</nlog>

I searched for this issue on Github but none of the solutions worked for me. And getting System.Data.SqlClient from Nuget should be enough but unfortunately, Mr. Nlog.config want someting else and I couldn't find out what.

Answer 1

It was because I wrote<dbProvider>System.Data.SqlClient</dbProvider> for my database target. It looks like someone should update the docs.

By the way, I don't know why deleting dbProvider worked for me.

The worked code is as follow:

<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" autoReload="true" internalLogLevel="info" internalLogFile="C:\Users\maliozt\source\MyProjects\MapApplication\MapApplication\Log2\asdaf.log">
<targets>
    <target
    xsi:type="File"
    name="mapFile"
    fileName="C:\Users\maliozt\source\MyProjects\MapApplication\MapApplication\Logs\${shortdate}.log"
    layout="${longdate}|${event-properties:item=EventId.Id}|${uppercase:${level}}|${logger}|${message} ${exception}" >
    </target>

    <target 
    xsi:type="Database" 
    name="mapDataBase">
        <commandText>INSERT INTO MapApplication.dbo.LogEntries(TimeStamp, Message, Level, Logger) VALUES(GETDATE(), @message, @level, @logger)</commandText>
        <parameter name="@message" layout="${message}" />
        <parameter name="@level" layout="${level}" />
        <parameter name="@logger" layout="${logger}" />
        <!--<dbProvider>System.Data.SqlClient</dbProvider>-->
        <connectionString>Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=master;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=True;ApplicationIntent=ReadWrite;MultiSubnetFailover=False</connectionString>
    </target>
</targets>
<rules>
    <logger name="*" minlevel="Warn" writeTo="mapFile" />
    <logger name="*" minlevel="Error" writeTo="mapDataBase" />
</rules>
</nlog>