AppSettingsGenerator

Quick start

Configure file from which settings should be generated in .csproj by adding:

<ItemGroup>
    <AdditionalFiles Include="appsettings.json" />
</ItemGroup>

Generated classes

For given configuration file:

{
  "Logging": {
    "LogLevel": {
        "Default": "Information",
        "Microsoft": "Warning"
    }
  }
}

Following classes will be generated.

namespace Configuration.Generated
{
    [CompilerGenerated]
    public partial class Logging
    {
        public LogLevel LogLevel { get; set; }

    }
}

namespace Configuration.Generated
{
    [CompilerGenerated]
    public partial class LogLevel
    {
        public string Default { get; set; }

        public string Microsoft { get; set; }

    }
}

namespace Configuration.Generated
{
    [CompilerGenerated]
    public partial class AppSettings
    {
        public Logging Logging { get; set; }
    }
}

AppSettings.cs is the root configuration file.

Extend generated classes

All classes are marked as partial, therefore if needed they can be extended by custom methods / properties.

namespace Configuration.Generated
{
    public partial class Logging
    {
        public bool Validate()
        {
            return !string.IsNullOrEmpty(this.LogLevel.Default);
        }
    }
}

Configuration Extensions

For every class generated there will be configuration extension generated to IServiceCollection interface. For given configuration

{
  "Logging": {
    "LogLevel": {
        "Default": "Information",
        "Microsoft": "Warning",
        "Microsoft.Hosting.Lifetime23": "Information"
    }
  }
}

Following extensions method will be generated:

public void ConfigureServices(IServiceCollection services)
{
    services.ConfigureAllSections(Configuration);
    services.ConfigureLogging(Configuration);
    services.ConfigureLogLevel(Configuration);
}

Which basicly adds proper section to IServiceCollection.

public static void ConfigureLogging(this IServiceCollection services, IConfiguration configuration)
{
    services.Configure<Configuration.Generated.Logging>(configuration.GetSection("Logging"));
}

ConfigureAllSections adds every sections at once. In our case it is equivalent to call these two lines:

 services.ConfigureLogging(Configuration);
 services.ConfigureLogLevel(Configuration);

Note: If you use ConfigureAllSections calling other methods are not necessary.

Diagnostics

• APG001 Error Configuration in .csproj is missing. To add it please follow instructions in section.
• APG002 Info Invalid identifier detected. If configuration file contains characters that are not valid in terms of C# class name or property name this information is reported. Given json property:

"Logging": {
   "LogLevel": {
       "Microsoft.Hosting.Lifetime23": "Information"
   }
 }

"Microsoft.Hosting.Lifetime": "Information" dot ('.') is not a valid character in property name, therefore it cannot be generated. In that case extension method to IConfiguration is generated. To use it Inject Microsoft.Extensions.Configuration.IConfiguration, add Configuration.Generated namespace and invoke IConfiguration.GetLoggingLogLevelMicrosoftHostingLifetime().