nlog无法发送日志到Oracle数据库

Question

We are trying to send logs to an Oracle Database but can't run the Nlogs because we receive an error message:

2021-11-18 13:00:25.5506 Error DatabaseTarget(Name=oracle): Failed to create ConnectionType from DBProvider=Oracle.ManagedDataAccess.Client.OracleConnection, Oracle.ManagedDataAccess Exception: System.IO.FileNotFoundException: Could not load file or assembly 'Oracle.ManagedDataAccess, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.
File name: 'Oracle.ManagedDataAccess, Culture=neutral, PublicKeyToken=null'
   at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, StackCrawlMarkHandle stackMark, ObjectHandleOnStack assemblyLoadContext, ObjectHandleOnStack type, ObjectHandleOnStack keepalive)
   at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, StackCrawlMark& stackMark, AssemblyLoadContext assemblyLoadContext)
   at System.RuntimeType.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase, StackCrawlMark& stackMark)
   at System.Type.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase)
   at NLog.Targets.DatabaseTarget.SetConnectionType()
   at NLog.Targets.DatabaseTarget.InitializeTarget()
2021-11-18 13:00:25.5726 Error Database Target[oracle]: Error initializing target Exception: System.IO.FileNotFoundException: Could not load file or assembly 'Oracle.ManagedDataAccess, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.
File name: 'Oracle.ManagedDataAccess, Culture=neutral, PublicKeyToken=null'
   at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, StackCrawlMarkHandle stackMark, ObjectHandleOnStack assemblyLoadContext, ObjectHandleOnStack type, ObjectHandleOnStack keepalive)
   at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, StackCrawlMark& stackMark, AssemblyLoadContext assemblyLoadContext)
   at System.RuntimeType.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase, StackCrawlMark& stackMark)
   at System.Type.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase)
   at NLog.Targets.DatabaseTarget.SetConnectionType()
   at NLog.Targets.DatabaseTarget.InitializeTarget()
   at NLog.Targets.Target.Initialize(LoggingConfiguration configuration)
2021-11-18 13:00:25.5726 Trace Initializing BufferingWrapper Target[OracleDatabase_wrapped](Database Target[oracle])

We have the Oracle.ManagedDataAccess.dll in the path folder where we run the process and our nlog config file is:

      <target xsi:type="BufferingWrapper" name="OracleDatabase" bufferSize="100" flushTimeout="5000" slidingTimeout="false">
      <target xsi:type="Database" name="oracle" dbProvider="Oracle.ManagedDataAccess.Client.OracleConnection, Oracle.ManagedDataAccess" connectionString="${ui-connection-strings:item=oracle}" keepConnection="true">
            <commandText>
                insert into ....
            </commandText>
            <parameter name="...." />

        </target>
      </target>

NLog: 4.7.7

Do we need to assembly the dll? Which could be the reason of this error?

Answer 1

NLog with.Net Core And Oracle Database.

I tried the below code and it's worked fine.

below Nugets you must include in project

• NLog
• NLog.Database
• NLog.Extenstion.Logging
• NLog.Web.AspNetCore
• Oracle.ManagedDataAccess.Core

Add connectionstring information in appsetings.json

nlog.config file must as below (edit connection string and log file path information as per you)

<?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="Warn"
      internalLogFile="C:\temp\Logs\internal-nlog4txt">
    <extensions>
        <add assembly="NLog.Database"/>
        <add assembly="NLog.Web.AspNetCore"/>
    </extensions>

    <targets>
        <target name="database"
                xsi:type="Database"
                connectionString="${configsetting:item:=ConnectionStrings.your_connectionstring_namefrom_appsettings_json_file}"
                dbProvider="Oracle.ManagedDataAccess.Client.OracleConnection,Oracle.ManagedDataAccess"
                commandText="INSERT INTO APPLICATIONLOG (ACTIONTIME,DETAILS) VALUES (sysdate,:details)"
                commandType="Text">
            <parameter name="details" layout="${message}" />
        </target>
    </targets>
    
    <rules>
        <logger name="*" minlevel="Trace" writeTo="database" />
    </rules>
</nlog>

---

Program.cs

     public class Program
    {
        public static void Main(string[] args)
        {
            var logger = NLogBuilder.ConfigureNLog("nlog.config").GetCurrentClassLogger();
            try
            {
                //logger.Debug("init main function");
                CreateWebHostBuilder(args).Build().Run();
            }
            catch (Exception ex)
            {
                logger.Error(ex, "Error in init");
                throw;
            }
            finally
            {
                NLog.LogManager.Shutdown();
            }
        }

        public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
            WebHost.CreateDefaultBuilder(args)
                .UseStartup<Startup>()
                .ConfigureLogging(logging =>
                {
                    logging.ClearProviders();
                    logging.SetMinimumLevel(LogLevel.Information);
                })
                .UseNLog();
    }

---

No configuration needed in Startup.cs class

Inject and use Logger in your controller like below

public class ValuesController : ControllerBase
{
    private readonly ILogger<ValuesController> _logger;

    public ValuesController(ILogger<ValuesController> logger)
    {
        _logger = logger;
    }

    [HttpGet("{id}")]
    public ActionResult<IEnumerable<string>> Get(int id)
    {
        _logger.LogInformation("Start : Getting item details for {ID} ", id);

        List<string> list = new List<string>();

        list.Add("A");
        list.Add("B");

        _logger.LogInformation($"Completed : Item details for  {string.Join(", ", list)}");

        return list;
    }
}

Thank you