c# - HttpClientFactory : Typed HttpClient with additional constructor arguments

Question

与 HttpClientFactory我们可以配置依赖注入(inject)来创建和管理 HttpClients 的生命周期:

public class GitHubService : IGitHubService
{
    public HttpClient Client { get; }

    public GitHubService(HttpClient client)
    {
        client.BaseAddress = new Uri("https://api.github.com/");
        // GitHub API versioning
        client.DefaultRequestHeaders.Add("Accept",
            "application/vnd.github.v3+json");
        // GitHub requires a user-agent
        client.DefaultRequestHeaders.Add("User-Agent",
            "HttpClientFactory-Sample");

        Client = client;
    }

    public async Task<IEnumerable<GitHubIssue>> GetAspNetDocsIssues()
    {
        var response = await Client.GetAsync(
            "/repos/aspnet/AspNetCore.Docs/issues?state=open&sort=created&direction=desc");

        response.EnsureSuccessStatusCode();

        using var responseStream = await response.Content.ReadAsStreamAsync();
        return await JsonSerializer.DeserializeAsync
            <IEnumerable<GitHubIssue>>(responseStream);
    }
}

然后在 Startup.cs 我们配置 DI:

services.AddHttpClient<GitHubService>();

但是，如果类型化客户端有额外的构造函数参数，应该如何提供这些？
例如，如果要传入存储库名称:

public class GitHubService : IGitHubService
{
    public HttpClient Client { get; }
    private readonly string _repositoryName;

    public GitHubService(HttpClient client, string repositoryName)
    {
        _repositoryName = repositoryName;

        client.BaseAddress = new Uri("https://api.github.com/");
        // GitHub API versioning
        client.DefaultRequestHeaders.Add("Accept",
            "application/vnd.github.v3+json");
        // GitHub requires a user-agent
        client.DefaultRequestHeaders.Add("User-Agent",
            "HttpClientFactory-Sample");

        Client = client;
    }

    public async Task<IEnumerable<GitHubIssue>> GetAspNetDocsIssues()
    {
        var response = await Client.GetAsync(
            $"/repos/aspnet/{_repositoryName}/issues?state=open&sort=created&direction=desc");

        response.EnsureSuccessStatusCode();

        using var responseStream = await response.Content.ReadAsStreamAsync();
        return await JsonSerializer.DeserializeAsync
            <IEnumerable<GitHubIssue>>(responseStream);
    }
}

也许这不是一个现实的例子，但是如何配置依赖注入(inject)来提供存储库名称？

Answer 1

我设法通过切换到命名客户端来完成这项工作:

//To start with, create a named client:
services.AddHttpClient("GitHubClient", ctx => { ctx.BaseAddress = new Uri("https://api.github.com/"); });

//Then set up DI for the TypedClient
services.AddTransient<IGitHubService>(ctx =>
{
    var clientFactory = ctx.GetRequiredService<IHttpClientFactory>();
    var httpClient = clientFactory.CreateClient("GitHubClient");
 
    return new GitHubService(httpClient, repositoryName);
});