ServiceCollectionExtensions.cs

using Microsoft.Extensions.DependencyInjection;
using TypedRest.Endpoints;

namespace TypedRest;

/// <summary>
/// Provides extension methods for <see cref="IServiceCollection"/>.
/// </summary>
public static class ServiceCollectionExtensions
{
    /// <summary>
    /// Registers <see cref="EntryEndpoint"/> for dependency injection.
    /// </summary>
    /// <param name="services">The <see cref="IServiceCollection"/>.</param>
    /// <param name="uri">The base URI of the REST API. Missing trailing slash will be appended automatically.</param>
    /// <returns>An <see cref="IHttpClientBuilder"/> that can be used to configure the underlying <see cref="HttpClient"/>.</returns>
    public static IHttpClientBuilder AddTypedRest(this IServiceCollection services, Uri uri)
        => services.AddTypedRest<EntryEndpoint>(uri);

    /// <summary>
    /// Registers a type derived from <see cref="EntryEndpoint"/> for dependency injection.
    /// </summary>
    /// <param name="services">The <see cref="IServiceCollection"/>.</param>
    /// <param name="uri">The base URI of the REST API. Missing trailing slash will be appended automatically.</param>
    /// <typeparam name="TEndpoint">The type of the <see cref="EntryEndpoint"/>. Must provide a constructor that accepts an <see cref="HttpClient"/>.</typeparam>
    /// <returns>An <see cref="IHttpClientBuilder"/> that can be used to configure the underlying <see cref="HttpClient"/>.</returns>
    public static IHttpClientBuilder AddTypedRest<TEndpoint>(this IServiceCollection services, Uri uri)
        where TEndpoint : EntryEndpoint
        => services.AddHttpClient<TEndpoint>(client => client.BaseAddress = uri);

    /// <summary>
    /// Registers a type derived from <see cref="EntryEndpoint"/> for dependency injection.
    /// </summary>
    /// <param name="services">The <see cref="IServiceCollection"/>.</param>
    /// <param name="uri">The base URI of the REST API. Missing trailing slash will be appended automatically.</param>
    /// <typeparam name="TInterface">The interface to register.</typeparam>
    /// <typeparam name="TEndpoint">The type of the <see cref="EntryEndpoint"/>. Must provide a constructor that accepts an <see cref="HttpClient"/>.</typeparam>
    /// <returns>An <see cref="IHttpClientBuilder"/> that can be used to configure the underlying <see cref="HttpClient"/>.</returns>
    public static IHttpClientBuilder AddTypedRest<TInterface, TEndpoint>(this IServiceCollection services, Uri uri)
        where TInterface : class
        where TEndpoint : EntryEndpoint, TInterface
        => services.AddHttpClient<TInterface, TEndpoint>(client => client.BaseAddress = uri);

    /// <summary>
    /// Adds HTTP Basic authentication.
    /// </summary>
    /// <param name="builder">The builder to apply the configuration to.</param>
    /// <param name="configureCredentials">A delegate that is used to configure <see cref="NetworkCredential"/>.</param>
    public static IHttpClientBuilder AddBasicAuth(this IHttpClientBuilder builder, Action<NetworkCredential> configureCredentials)
        => builder.ConfigureHttpClient(httpClient =>
        {
            var credentials = new NetworkCredential();
            configureCredentials(credentials);
            httpClient.AddBasicAuth(credentials);
        });

    /// <summary>
    /// Adds HTTP Basic authentication.
    /// </summary>
    /// <param name="builder">The builder to apply the configuration to.</param>
    /// <param name="credentials">A credential provider. Will be queried using <see cref="HttpClient.BaseAddress"/> as the uri and "Basic" as the authType.</param>
    public static IHttpClientBuilder AddBasicAuth(this IHttpClientBuilder builder, ICredentials credentials)
        => builder.ConfigureHttpClient(httpClient =>
        {
            var networkCredential = credentials.GetCredential(httpClient.BaseAddress ?? throw new InvalidOperationException("HttpClient.BaseAddress must be set."), "Basic");
            if (networkCredential != null)
                httpClient.AddBasicAuth(networkCredential);
        });
}