DRN.Framework.Utils 0.2.2-preview008

DRN.Framework.Utils package contains common codes for other DRN.Framework packages and projects developed with DRN.Framework.

Module

DRN.Utils can be added with following module

namespace DRN.Framework.Utils;

public static class UtilsModule
{
    public static IServiceCollection AddDrnUtils(this IServiceCollection collection)
    {
        collection.AddServicesWithAttributes();

        return collection;
    }
}

Dependency Injection with Attributes

Each module should be created in the assembly that will be scanned.

public static class InfraModule
{
    public static IServiceCollection AddSampleInfraServices(this IServiceCollection sc)
    {
        sc.AddServicesWithAttributes();

        return sc;
    }
}

Services resolution for attribute based services can be validated with a single line.

serviceProvider.ValidateServicesAddedByAttributes();

Attribute based dependency injection reduces wiring efforts and helps developer to focus on developing. This approach also improves service resolution validation during startup and integration testing.

    [Theory]
    [DataInlineContext]
    public void Validate_Sample_Dependencies(TestContext context)
    {
        context.ServiceCollection.AddSampleApplicationServices();
        context.ServiceCollection.AddSampleInfraServices();
        context.ValidateServices();
    }

Lifetime Attributes

Example attribute usage:

[Transient<IIndependent>]
public class Independent : IIndependent
{
}

Following attributes marks services with a lifetime and when service collection called with AddServicesWithAttributes method in the assembly marked belong they are automatically added.

namespace DRN.Framework.Utils.DependencyInjection.Attributes;

public class LifetimeAttribute<TService>(ServiceLifetime serviceLifetime, bool tryAdd = true, object? key = null)
    : LifetimeAttribute(serviceLifetime, typeof(TService), tryAdd, key);

public class LifetimeWithKeyAttribute<TService>(ServiceLifetime serviceLifetime, object key, bool tryAdd = true)
    : LifetimeAttribute(serviceLifetime, typeof(TService), tryAdd, key);

public class ScopedAttribute<TService>(bool tryAdd = true) : LifetimeAttribute<TService>(ServiceLifetime.Scoped, tryAdd);

public class ScopedWithKeyAttribute<TService>(object key, bool tryAdd = true) : LifetimeWithKeyAttribute<TService>(ServiceLifetime.Scoped, key, tryAdd);

public class TransientAttribute<TService>(bool tryAdd = true) : LifetimeAttribute<TService>(ServiceLifetime.Transient, tryAdd);

public class TransientWithKeyAttribute<TService>(object key, bool tryAdd = true) : LifetimeWithKeyAttribute<TService>(ServiceLifetime.Transient, key, tryAdd);

public class SingletonAttribute<TService>(bool tryAdd = true) : LifetimeAttribute<TService>(ServiceLifetime.Singleton, tryAdd);

public class SingletonWithKeyAttribute<TService>(object key, bool tryAdd = true) : LifetimeWithKeyAttribute<TService>(ServiceLifetime.Singleton, key, tryAdd);

HasServiceCollectionModuleAttribute

Attributes derived from HasServiceCollectionModuleAttribute can be used to mark custom service collection modules. In the following example HasDrnContextServiceCollectionModuleAttribute marks DrnContext<TContext> and its service collection module. This way dbContexts inherited from DrnContext doesn't need a lifetime attribute and they can be registered by AddServicesWithAttributes with their custom factory.

This offers following flexibility:

1. ServiceCollectionModule of DrnContexts are defined in DRN.Framework.EntityFramework
2. Inherited dbContexts are defined in user defined projects and points a module in another project.
3. AddServicesWithAttributes extension method defined in DRN.Framework.Utils registers them without depending DRN.Framework.EntityFramework project

public class HasDrnContextServiceCollectionModuleAttribute : HasServiceCollectionModuleAttribute
{
    static HasDrnContextServiceCollectionModuleAttribute()
    {
        ModuleMethodInfo = typeof(ServiceCollectionExtensions).GetMethod(nameof(ServiceCollectionExtensions.AddDbContextsWithConventions))!;
    }
}

[HasDrnContextServiceCollectionModule]
public abstract class DrnContext<TContext> : DbContext, IDesignTimeDbContextFactory<TContext>, IDesignTimeServices where TContext : DbContext, new()
{
...

HasServiceCollectionModuleAttribute has PostStartupValidationAsync when,

• ValidateServicesAddedByAttributes extension method called from service provider,
• PostStartupValidationAsync will be called if all services resolved successfully.
• For instance, DrnContext can apply EF migrations after service provider services resolved successfully.

Configurations

Following configuration sources can be used to add configurations from different sources

• JsonSerializerConfigurationSource converts poco objects to configuration
• RemoteJsonConfigurationSource fetches remote configuration (experimental and incomplete)

AppSettings

Following IAppSettings interface is defined and can be used to obtain appsettings. It has utility methods that allow fail fast.

namespace DRN.Framework.Utils.Settings;

public interface IAppSettings
{
    IConfiguration Configuration { get; }
    bool TryGetConnectionString(string name, out string connectionString);
    string GetRequiredConnectionString(string name);
    bool TryGetSection(string key, out IConfigurationSection section);
    IConfigurationSection GetRequiredSection(string key);
}

ExtensionMethods

• ServiceCollectionExtensions
  • ReplaceInstance
  • ReplaceTransient
  • ReplaceScoped
  • ReplaceSingleton
  • GetAllAssignableTo<TService>
• StringExtensions
  • ToStream
• TypeExtensions
  • MakeGenericMethod
• AssemblyExtensions
  • GetTypesAssignableTo

Commit Info

Author: Duran Serkan KILIÇ
Date: 2024-03-18 10:49:47 +0300
Hash: 8d61c90bb7237377c11ffd70e81a219221713a98