how to implement NLog in webapi

https://www.c-sharpcorner.com/article/how-to-implement-nlog-in-webapi/

In this topic I will cover the following things

1-    Definition

3-    Log Level

4-    Implementation

After reading this article I hope you will be able to use easily.

Definition :

NLog is a flexible and free logging platform for various .NET platforms, including .NET standard. NLog makes it easy to write to several targets. (database, file, eventviewer)

Log levels

The log levels, in sliding request, are as per the following:

S.N	Level	Use
1	Fatal	Something terrible occurred; application is going down
2	Error	Something fizzled; application might possibly proceed
3	Warn	Something surprising; application will proceed
4	Info	Normal conduct like mail sent, client refreshed profile and so on.
5	Debug	For troubleshooting; executed question, client confirmed, session terminated
6	Trace	For follow troubleshooting; start technique X, end strategy X

Implementation

Step 1

Click Visual studio> Select File>New>Project

 

Step 2

Select Web> Asp.net Web Application > Give your project name, for me I have given NLogTest then click on Ok

 

Step 3

Select WebApi then click on OK

 

Step 4

Now you have to add NLog to your project.

So follow the steps Right click on your project solution then click on Manage NugGet Packeses

And then install.

 

After click on install you will get following window.

 

Click OK on this pop up windo, after successful installed you will get dll in your project reference

 

Now your half part of configuration is done!

Let go to next level

Step 5

Now add following code in your config file

1. <configSections>  
2.   
3. <section name="nlog" type="NLog.Config.ConfigSectionHandler, NLog" />  
4.   
5. </configSections>  
6.   
7. <nlog xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">  
8.   
9. <targets>  
10.   
11. <target name="logfile" xsi:type="File" fileName="${basedir}/MyLogs/${date:format=yyyy-MM-dd}-api.log" />  
12.   
13. <target name="eventlog" xsi:type="EventLog" layout="${message}" log="Application" source=" My Custom Api Services" />  
14.   
15. <target name="database" type="Database" connectionString="Data Source=your sql source;initial catalog=YourDbNameDb;user id=u1;password=p1;MultipleActiveResultSets=True;">  
16.   
17. <commandText>  
18.   
19. insert into ExceptionLog ([TimeStamp],[Level],Logger, [Message], UserId, Exception, StackTrace) values (@TimeStamp, @Level, @Logger, @Message,  
20.   
21. case when len(@UserID) = 0 then null  
22.   
23. else @UserId  
24.   
25. end,  
26.   
27. @Exception, @StackTrace);  
28.   
29. </commandText>  
30.   
31. <parameter name="@TimeStamp" layout="${date}"/>  
32.   
33. <parameter name="@Level" layout="${level}"/>  
34.   
35. <parameter name="@Logger" layout="${logger}"/>  
36.   
37. <parameter name="@Message" layout="${message}"/>  
38.   
39. <parameter name="@UserId" layout="${mdc:user_id}"/>  
40.   
41. <parameter name="@Exception" layout="${exception}"/>  
42.   
43. <parameter name="@StackTrace" layout="${stacktrace}"/>  
44.   
45. <dbProvider>System.Data.SqlClient</dbProvider>  
46.   
47. </target>  
48.   
49. </targets>  
50.   
51. <rules>  
52.   
53. <!-- add your logging rules here -->  
54.   
55. <logger name="*" minlevel="Debug" writeTo="database" />  
56.   
57. <logger name="*" minlevel="Trace" writeTo="logfile" />  
58.   
59. <logger name="*" minlevel="Trace" writeTo="eventlog" />  
60.   
61. </rules>  
62.   
63. </nlog>  

Please refer below screen

 

Step 6

Create your db Script

1. CREATE TABLE [dbo].[ExceptionLog](  
2.   
3. [Id] [int] IDENTITY(1,1) NOT NULL,  
4.   
5. [TimeStamp] [datetime] NOT NULL,  
6.   
7. [Level] [varchar](100) NOT NULL,  
8.   
9. [Logger] [varchar](1000) NOT NULL,  
10.   
11. [Message] [varchar](3600) NOT NULL,  
12.   
13. [UserId] [int] NULL,  
14.   
15. [Exception] [varchar](3600) NULL,  
16.   
17. [StackTrace] [varchar](3600) NULL,  
18.   
19. CONSTRAINT [PK_ExceptionLog] PRIMARY KEY CLUSTERED  
20.   
21. (  
22.   
23. [Id] ASC  
24.   
25. )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]  
26.   
27. ) ON [PRIMARY]  

Step 7

Go to your home controller

And add following code

1. using NLog;  
2.   
3. using System;  
4.   
5. using System.Web.Mvc;  
6.   
7. namespace NLogTest.Controllers  
8.   
9. {  
10.   
11. public class HomeController : Controller  
12.   
13. {  
14.   
15. private static Logger logger = LogManager.GetCurrentClassLogger();  
16.   
17. public ActionResult Index()  
18.   
19. {  
20.   
21. ViewBag.Title = "Home Page";  
22.   
23. logger.Info("Hell You have visited the Index view" + Environment.NewLine + DateTime.Now);  
24.   
25. return View();  
26.   
27. }  
28.   
29. public ActionResult About()  
30.   
31. {  
32.   
33. ViewBag.Message = "Your app description page.";  
34.   
35. logger.Info("hello now You have visited the About view" + Environment.NewLine + DateTime.Now);  
36.   
37. return View();  
38.   
39. }  
40.   
41. }  
42.   
43. }  

Now run the application

And open your sql you will see following logs inserted in your dB

 

You can see in your event viewer

 

You can see in your txt file

 

Now your can open your event viewer in following ways

To access the Event Viewer

1. Right click on the Start button and select Control Panel > System & Security and double-click Administrative tools.

2. Double-click Event Viewer.

3. Select the type of logs that you wish to review (error, information etc..)

Or

Press Windows+R to open the Run dialog, enter eventvwr