Question 246865 in ASP.NET Question posted in
The official documentation can be found here.

Trying to add logging in ASP.NET Core function app

I am currently working with an ASP.NET Core v6 Function App v4 and want to add logging so I can save the logs to the database.

In past projects I’ve used Log4Net package, I see there is a nuget package that allows us to use it for ASP.NET Core v6, but it’s mostly for web and API projects with Program.cs files. The Function App only comes with a Startup.cs and doesn’t allow you to add ILogger.

I am wondering if there is a way or a work around in adding this tool or logging to the project in general or what other options there are our there.

Here is the link to the repo/docs for the nuget package.
Microsoft.Extensions.Logging.Log4Net.AspNetCore

And the original Log4Net site:

Log4net

Added like so and get the error:

IFunctionHostBuilder does not contain a definition of ‘Logging’ and no accessible extension methedon ‘Logging’ accepting a first argument of type ‘IFunctionsHostbuilder’ could not be found (are you missing a using dir or an assembly ref)?

Code:

 public override void Configure(IFunctionsHostBuilder builder)
 {
    //...
    builder.Logging.AddLog4Net();
    //...
 }

I’m pretty new to the Function apps so any guidance would be grateful.

Tags:

2

Answers


  1. 0

    You can get rid of Startup.cs file in favor of one-file Program.cs. Configuration is then almost the same as in ASP.NET Core app

    using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;

var hostBuilder = new HostBuilder()
    .ConfigureFunctionsWorkerDefaults();

hostBuilder.ConfigureLogging(builder =>
{
    builder.ClearProviders();
    builder.AddLog4Net("log4net.config");
});
var host = hostBuilder.Build();

host.Run();

    Function

    using System.Net;
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.Extensions.Logging;

namespace Company.FunctionApp2;

public  class MyHttpTriggerFunction
{
    private readonly ILogger<MyHttpTriggerFunction> logger;

    public MyHttpTriggerFunction(ILogger<MyHttpTriggerFunction> logger)
    {
        this.logger = logger;
    }

    [Function("MyHttpTriggerFunction")]
    public  HttpResponseData Run([HttpTrigger(AuthorizationLevel.Function, "get", "post")] HttpRequestData req)
    {
        logger.LogInformation("C# HTTP trigger function processed a request.");

        var response = req.CreateResponse(HttpStatusCode.OK);
        response.Headers.Add("Content-Type", "text/plain; charset=utf-8");

        response.WriteString("Welcome to Azure Functions!");

        return response;
        
    }
}

    UPD:
    Your csproj file should contain:

    <ItemGroup>
    <PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.18.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http" Version="3.0.12" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.13.0" />
    <PackageReference Include="Microsoft.Extensions.Logging.Log4Net.AspNetCore" Version="6.1.0" />
</ItemGroup>

    To make app isolated, set configuration value in local.settings.json

    {
    "IsEncrypted": false,
    "Values": {
        "AzureWebJobsStorage": "UseDevelopmentStorage=true",
        "FUNCTIONS_WORKER_RUNTIME": "dotnet-isolated" <--- this
    }
}

    and in Azure

    Azure

    Login or Signup to reply.
  2. 0

    You may consider serilog, will be much more easier to use for non-isolated function. No startup.cs/program.cs or other configuration needed.
    Create a project like below.
    enter image description here
    Install package Serilog Serilog.Sinks.Console``Serilog.Sinks.MSSqlServer
    Modify the Function1.cs like below

        public static class Function1
    {
        [FunctionName("Function1")]
        public static async Task<IActionResult> Run(
            [HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)] HttpRequest req)
        {
            var log = new LoggerConfiguration()
            .WriteTo.Console(new JsonFormatter())
           .WriteTo.MSSqlServer(
                        connectionString: "Data Source = 192.168.2.68; Initial Catalog = LogDb; User ID = sa; Password = xxxxx; TrustServerCertificate = True",
                        tableName:"function1_log",
                        autoCreateSqlTable:true               
                 )
            .CreateLogger();

            log.Information("A serilog information");
...

    Test
    enter image description here
    Check Sqlserver
    enter image description here
    Reference: https://stackify.com/logging-azure-functions/

    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search