Add project files.

ApacheTech.Common.DependencyInjection.sln

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+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.31911.196
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ApacheTech.Common.DependencyInjection", "ApacheTech.Common.DependencyInjection\ApacheTech.Common.DependencyInjection.csproj", "{545558F3-2E21-42BA-8BD8-DCB850F29D88}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Package|Any CPU = Package|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{545558F3-2E21-42BA-8BD8-DCB850F29D88}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{545558F3-2E21-42BA-8BD8-DCB850F29D88}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{545558F3-2E21-42BA-8BD8-DCB850F29D88}.Package|Any CPU.ActiveCfg = Debug|Any CPU
+		{545558F3-2E21-42BA-8BD8-DCB850F29D88}.Package|Any CPU.Build.0 = Debug|Any CPU
+		{545558F3-2E21-42BA-8BD8-DCB850F29D88}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{545558F3-2E21-42BA-8BD8-DCB850F29D88}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {B65743EB-7EEA-4B68-BCBF-E6C8B0D24DBE}
+	EndGlobalSection
+EndGlobal

ApacheTech.Common.DependencyInjection/Abstractions/IServiceCollection.cs

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+using System;
+
+// ReSharper disable UnusedMemberInSuper.Global
+// ReSharper disable UnusedMember.Global
+
+namespace ApacheTech.Common.Extensions.Abstractions
+{
+    /// <summary>
+    ///     An IOC Container, which holds references to registered types of services, and their instances.
+    /// </summary>
+    public interface IServiceCollection
+    {
+        /// <summary>
+        ///     Registers a raw service descriptor, pre-populated with meta-data for the service.
+        /// </summary>
+        /// <param name="descriptor">The pre-populated descriptor for the service to register.</param>
+        /// <seealso cref="ServiceDescriptor"/>
+        /// 
+        void Register(ServiceDescriptor descriptor);
+
+        /// <summary>
+        ///     Registers a service as a singleton. Only one instance of the service will be created within the container.
+        /// </summary>
+        /// <typeparam name="TService">The type of service to register.</typeparam>
+        /// <seealso cref="ServiceLifetime.Singleton"/>
+        /// 
+        void RegisterSingleton<TService>() where TService : class;
+
+        /// <summary>
+        ///     Registers a service as a singleton. Only one instance of the service will be created within the container.
+        /// </summary>
+        /// <typeparam name="TService">The type of service to register.</typeparam>
+        /// <typeparam name="TImplementation">The type of implementation to use.</typeparam>
+        /// <seealso cref="ServiceLifetime.Singleton"/>
+        void RegisterSingleton<TService, TImplementation>() where TImplementation : TService;
+
+        /// <summary>
+        ///     Registers a service as a singleton. Only one instance of the service will be created within the container.
+        /// </summary>
+        /// <typeparam name="TService">The type of service to register.</typeparam>
+        /// <param name="implementationFactory">The factory that creates the service.</param>
+        /// <seealso cref="ServiceLifetime.Singleton"/>
+        void RegisterSingleton<TService>(Func<IServiceResolver, TService> implementationFactory) where TService : class;
+
+        /// <summary>
+        ///     Registers a service as a singleton. Only one instance of the service will be created within the container.
+        /// </summary>
+        /// <typeparam name="TService">The instance to register.</typeparam>
+        /// <seealso cref="ServiceLifetime.Singleton"/>
+        void RegisterSingleton<TService>(TService implementation);
+
+        /// <summary>
+        ///     Registers a service as a singleton. A new instance of the service will be created each time it is resolved.
+        /// </summary>
+        /// <typeparam name="TService">The type of service to register.</typeparam>
+        /// <seealso cref="ServiceLifetime.Transient"/>
+        void RegisterTransient<TService>() where TService : class;
+
+        /// <summary>
+        ///     Registers a service as a singleton. A new instance of the service will be created each time it is resolved.
+        /// </summary>
+        /// <typeparam name="TService">The type of service to register.</typeparam>
+        /// <typeparam name="TImplementation">The type of implementation to use.</typeparam>
+        /// <seealso cref="ServiceLifetime.Transient"/>
+        void RegisterTransient<TService, TImplementation>() where TImplementation : TService;
+
+        /// <summary>
+        ///     Registers a service as a singleton. A new instance of the service will be created each time it is resolved.
+        /// </summary>
+        /// <typeparam name="TService">The type of service to register.</typeparam>
+        /// <param name="implementationFactory">The factory that creates the service.</param>
+        /// <seealso cref="ServiceLifetime.Transient"/>
+        void RegisterTransient<TService>(Func<IServiceResolver, TService> implementationFactory) where TService : class;
+
+        /// <summary>
+        ///     Build a service resolver, to access services within this collection.
+        /// </summary>
+        /// <returns>An IOC Service Resolver.</returns>
+        IServiceResolver Build();
+    }
+}

ApacheTech.Common.DependencyInjection/Abstractions/IServiceResolver.cs

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+using System;
+
+// ReSharper disable UnusedMemberInSuper.Global
+// ReSharper disable UnusedMember.Global
+
+namespace ApacheTech.Common.Extensions.Abstractions
+{
+    /// <summary>
+    ///     Defines a mechanism for retrieving a service object; that is, an object that provides custom support to other objects.
+    /// </summary>
+    public interface IServiceResolver : IDisposable
+    {
+        /// <summary>
+        ///     Gets the service object of the specified type.
+        /// </summary>
+        /// <param name="serviceType">An object that specifies the type of service object to get.</param>
+        /// <returns>A service object of type <paramref name="serviceType" />.
+        /// 
+        /// -or-
+        /// 
+        /// <see langword="null" /> if there is no service object of type <paramref name="serviceType" />.</returns>
+        object GetService(Type serviceType);
+
+        /// <summary>
+        ///     Creates an object of a specified type, using the IOC Container to resolve dependencies.
+        /// </summary>
+        /// <param name="serviceType">An object that specifies the type of service object to get.</param>
+        /// <param name="args">An optional list of arguments, sent the the constructor of the instantiated class.</param>
+        /// <returns>A service object of type <paramref name="serviceType" />.
+        /// 
+        /// -or-
+        /// 
+        /// <see langword="null" /> if no object of type <paramref name="serviceType" /> can be instantiated from the service collection.</returns>
+        object CreateInstance(Type serviceType, params object[] args);
+
+        /// <summary>
+        ///     Creates an object of a specified type, using the IOC Container to resolve dependencies.
+        /// </summary>
+        /// <typeparam name="T">The type of object to create.</typeparam>
+        /// <param name="args">An optional list of arguments, sent the the constructor of the instantiated class.</param>
+        /// <returns>An object of type <typeparamref name="T" />.
+        /// 
+        /// -or-
+        /// 
+        /// <see langword="null" /> if there is no object of type <typeparamref name="T" /> can be instantiated from the service collection.</returns>
+        T CreateInstance<T>(params object[] args) where T : class;
+
+        /// <summary>
+        ///     Gets the service object of the specified type.
+        /// </summary>
+        /// <typeparam name="T">The type of service object to get.</typeparam>
+        /// <returns>A service object of type <typeparamref name="T" />.
+        /// 
+        /// -or-
+        /// 
+        /// <see langword="null" /> if there is no service object of type <typeparamref name="T" />.</returns>
+        T Resolve<T>();
+    }
+}

ApacheTech.Common.DependencyInjection/Abstractions/ObjectFactory.cs

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+using System;
+
+namespace ApacheTech.Common.Extensions.Abstractions
+{
+    /// <summary>
+    /// The result of <see cref="ActivatorUtilities.CreateFactory(Type, Type[])"/>.
+    /// </summary>
+    /// <param name="serviceProvider">The <see cref="IServiceProvider"/> to get service arguments from.</param>
+    /// <param name="arguments">Additional constructor arguments.</param>
+    /// <returns>The instantiated type.</returns>
+    public delegate object ObjectFactory(IServiceProvider serviceProvider, object[] arguments);
+}

ApacheTech.Common.DependencyInjection/Abstractions/ServiceDescriptor.cs

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+using System;
+
+// ReSharper disable UnusedMember.Global
+
+namespace ApacheTech.Common.Extensions.Abstractions
+{
+    /// <summary>
+    ///     Describes a service with its service type, implementation, and lifetime.
+    /// </summary>
+    public class ServiceDescriptor
+    {
+        /// <summary>
+        ///     Gets the type of the service.
+        /// </summary>
+        /// <value>The <see cref="Type"/> of the service.</value>
+        public Type ServiceType { get; }
+
+        /// <summary>
+        ///     Gets the type of the implementation.
+        /// </summary>
+        /// <value>The <see cref="Type"/> of the implementation of the service.</value>
+        public Type ImplementationType { get; }
+
+        /// <summary>
+        ///     Gets the concrete implementation, which gets returned to the user.
+        /// </summary>
+        /// <value>The implementation of the service.</value>
+        public object Implementation { get; internal set; }
+
+        /// <summary>
+        /// Specifies the lifetime of a service in an <see cref="IServiceCollection" />.
+        /// </summary>
+        /// <value>The <see cref="ServiceLifetime"/> of the service.</value>
+        public ServiceLifetime Lifetime { get; } 
+
+        /// <summary>
+        /// 	Initialises a new instance of the <see cref="ServiceDescriptor"/> class.
+        /// </summary>
+        /// <param name="implementation">The concrete implementation, which gets returned to the user.</param>
+        /// <param name="lifetime">The <see cref="ServiceLifetime"/> of the service.</param>
+        public ServiceDescriptor(object implementation, ServiceLifetime lifetime)
+        {
+            ServiceType = implementation.GetType();
+            Implementation = implementation;
+            ImplementationType = implementation.GetType();
+            Lifetime = lifetime;
+        }
+
+        /// <summary>
+        /// 	Initialises a new instance of the <see cref="ServiceDescriptor"/> class.
+        /// </summary>
+        /// <param name="serviceType">The <see cref="Type"/> of the service.</param>
+        /// <param name="lifetime">The <see cref="ServiceLifetime"/> of the service.</param>
+        public ServiceDescriptor(Type serviceType, ServiceLifetime lifetime)
+        {
+            ServiceType = serviceType;
+            Lifetime = lifetime;
+        }
+
+        /// <summary>
+        ///     Initialises a new instance of <see cref="ServiceDescriptor"/> with the specified <paramref name="implementationType"/>.
+        /// </summary>
+        /// <param name="serviceType">The <see cref="Type"/> of the service.</param>
+        /// <param name="implementationType">The <see cref="Type"/> implementing the service.</param>
+        /// <param name="lifetime">The <see cref="ServiceLifetime"/> of the service.</param>
+        public ServiceDescriptor(Type serviceType, Type implementationType, ServiceLifetime lifetime)
+        {
+            ServiceType = serviceType;
+            Lifetime = lifetime;
+            ImplementationType = implementationType;
+        }
+
+        /// <summary>
+        /// 	Initialises a new instance of the <see cref="ServiceDescriptor"/> class.
+        /// </summary>
+        /// <param name="serviceType">The <see cref="Type"/> of the service.</param>
+        /// <param name="implementation">The concrete implementation, which gets returned to the user.</param>
+        /// <param name="lifetime">The <see cref="ServiceLifetime"/> of the service.</param>
+        public ServiceDescriptor(Type serviceType, object implementation, ServiceLifetime lifetime)
+        {
+            ServiceType = serviceType;
+            Lifetime = lifetime;
+            ImplementationType = implementation.GetType();
+            Implementation = implementation;
+        }
+    }
+}

ApacheTech.Common.DependencyInjection/Abstractions/ServiceLifetime.cs

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+namespace ApacheTech.Common.Extensions.Abstractions
+{
+    /// <summary>
+    ///     Specifies the lifetime of a service in an <see cref="IServiceCollection" />.
+    /// </summary>
+    public enum ServiceLifetime
+    {
+        /// <summary>
+        ///     Specifies that a single instance of the service will be created.
+        /// </summary>
+        Singleton,
+
+        /// <summary>
+        ///     Specifies that a new instance of the service will be created every time it is requested.
+        /// </summary>
+        Transient,
+    }
+}