ASP.NET Core configuration for .NET Core console application

ASP.NET Core support a new configuration system as seen here: https://docs.asp.net/en/latest/fundamentals/configuration.html

Is this model also supported in .NET Core console applications?

If not what is alternate to the previous app.config and ConfigurationManager model?


Solution 1:

For a .NET Core 2.0 console app, I did the following:

  1. Create a new file named appsettings.json at the root of the project (the file name can be anything)
  2. Add my specific settings to that file as json. For example:
{
  "myKey1" :  "my test value 1", 
  "myKey2" :  "my test value 2", 
  "foo" :  "bar" 
}
  1. Configure to copy the file to the output directory whenever the project is built (in VS -> Solution Explorer -> right-click file -> select 'Properties' -> Advanced -> Copy to Output Directory -> select 'Copy Always')

  2. Install the following nuget package in my project:

    • Microsoft.Extensions.Configuration.Json
  3. Add the following to Program.cs (or wherever Main() is located):

    static void Main(string[] args)
    {
        var builder = new ConfigurationBuilder()
            .SetBasePath(Directory.GetCurrentDirectory())
            .AddJsonFile("appsettings.json");
    
        var configuration = builder.Build();
    
        // rest of code...
    }
    
  4. Then read the values using either of the following ways:

    string myKey1 = configuration["myKey1"];
    Console.WriteLine(myKey1);
    
    string foo = configuration.GetSection("foo").Value;
    Console.WriteLine(foo);
    

More info: https://docs.microsoft.com/en-us/aspnet/core/fundamentals/configuration?tabs=basicconfiguration#simple-configuration

Solution 2:

You can use this code snippet. It includes Configuration and DI.

public class Program
{
    public static ILoggerFactory LoggerFactory;
    public static IConfigurationRoot Configuration;

    public static void Main(string[] args)
    {
        Console.OutputEncoding = Encoding.UTF8;

        string environment = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT");

        if (String.IsNullOrWhiteSpace(environment))
            throw new ArgumentNullException("Environment not found in ASPNETCORE_ENVIRONMENT");

        Console.WriteLine("Environment: {0}", environment);

        var services = new ServiceCollection();

        // Set up configuration sources.
        var builder = new ConfigurationBuilder()
            .SetBasePath(Path.Combine(AppContext.BaseDirectory))
            .AddJsonFile("appsettings.json", optional: true);
        if (environment == "Development")
        {

            builder
                .AddJsonFile(
                    Path.Combine(AppContext.BaseDirectory, string.Format("..{0}..{0}..{0}", Path.DirectorySeparatorChar), $"appsettings.{environment}.json"),
                    optional: true
                );
        }
        else
        {
            builder
                .AddJsonFile($"appsettings.{environment}.json", optional: false);
        }

        Configuration = builder.Build();

        LoggerFactory = new LoggerFactory()
            .AddConsole(Configuration.GetSection("Logging"))
            .AddDebug();

        services
            .AddEntityFrameworkNpgsql()
            .AddDbContext<FmDataContext>(o => o.UseNpgsql(connectionString), ServiceLifetime.Transient);

        services.AddTransient<IPackageFileService, PackageFileServiceImpl>();

        var serviceProvider = services.BuildServiceProvider();

        var packageFileService = serviceProvider.GetRequiredService<IPackageFileService>();

        ............
    }
}

Oh, and don't forget to add in the project.json

{
  "version": "1.0.0-*",
  "buildOptions": {
    "emitEntryPoint": true,
    "copyToOutput": {
      "includeFiles": [
        "appsettings.json",
        "appsettings.Integration.json",
        "appsettings.Production.json",
        "appsettings.Staging.json"
      ]
    }
  },

  "publishOptions": {
    "copyToOutput": [
      "appsettings.json",
      "appsettings.Integration.json",
      "appsettings.Production.json",
      "appsettings.Staging.json"
    ]
  },
...
}