If I have a service, IService, that needs to access the Request or Response objects given by ControllerBase like I would in a controller:

[HttpGet]
public async Task<IActionResult> HelloWorldAsync() {
    Response.Cookies.Append("Hello World", "Goodbye World");
    return Ok();
}

How would I access Response from within a service? What would I need to inject? Or do I need to resort to passing it through the method of the service, like so:

[HttpGet]
public async Task<IActionResult> HelloWorldAsync() {
    await _myService.FooWithCookies(Response);
    return Ok();
}

CodePudding user response：

If you need the Request or the Response then you may inject an IHttpContextAccessor into you service through ctor injection.

public class YourService
{
    private readonly IHttpContextAccessor httpContextAccessor;

    public YourService(IHttpContextAccessor httpContextAccessor)
    {
        this.httpContextAccessor = httpContextAccessor;
    }

    public void SomeMethod()
    {
        var response = httpContextAccessor.HttpContext.Response;
    }
}

In your Startup.cs file:

public void ConfigureServices(IServiceCollection services)
{
    services.AddHttpContextAccessor();

    // rest is omitted for clarity.
}

CodePudding user response：

In your ConfigureServices code, you'll want to ensure you're adding the HTTP Context accessor:

services.AddHttpContextAccessor();

And then in your service you can inject it:

public class MyService
{
    private readonly IHttpContextAccessor _contextAccessor;

    public MyService(IHttpContextAccessor contextAccessor)
    {
        _contextAccessor = contextAccessor;
    }

    public async Task FooWithCookies()
    {
        HttpRequest request = _contextAccessor.HttpContext.Request;
        HttpResponse response = _contextAccessor.HttpContext.Response;
    }
}

Note that IHttpContextAccessor is registered as singleton, which can be useful in some situations.

See more info in the documentation: Use HttpContext from custom components

Depending on what your actual needs are, you might want to look at implementing a custom IActionResult, which contains a method with the following signature:

public System.Threading.Tasks.Task ExecuteResultAsync (Microsoft.AspNetCore.Mvc.ActionContext context);

This gives you access to the context via ActionContext, and also includes details of the specific action being executed.

Then FooWithCookies could return it (e.g. return new MyActionResult(someConstructorParameter);) and then you could simply pass it on in the action (e.g. return await _myService.FooWithCookies();).