[1.x] Back function

InertiaCore/Inertia.cs

@@ -1,4 +1,5 @@
-using System.Runtime.CompilerServices;
+using System.Net;
+using System.Runtime.CompilerServices;
 using InertiaCore.Props;
 using InertiaCore.Utils;
 using Microsoft.AspNetCore.Html;
@@ -27,6 +28,9 @@ public static class Inertia
 
     public static LocationResult Location(string url) => _factory.Location(url);
 
+    public static BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) =>
+        _factory.Back(fallbackUrl, statusCode);
+
     public static void Share(string key, object? value) => _factory.Share(key, value);
 
     public static void Share(IDictionary<string, object?> data) => _factory.Share(data);

InertiaCore/ResponseFactory.cs

@@ -20,6 +20,7 @@ internal interface IResponseFactory
     public void Version(Func<string?> version);
     public string? GetVersion();
     public LocationResult Location(string url);
+    public BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther);
     public void Share(string key, object? value);
     public void Share(IDictionary<string, object?> data);
     public AlwaysProp Always(object? value);
@@ -109,6 +110,9 @@ public async Task<IHtmlContent> Html(dynamic model)
 
     public LocationResult Location(string url) => new(url);
 
+    public BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) =>
+        new(fallbackUrl, statusCode);
+
     public void Share(string key, object? value)
     {
         var context = _contextAccessor.HttpContext!;

InertiaCore/Utils/BackResult.cs

@@ -0,0 +1,25 @@
+using System.Net;
+using InertiaCore.Extensions;
+using Microsoft.AspNetCore.Mvc;
+
+namespace InertiaCore.Utils;
+
+public class BackResult : IActionResult
+{
+    private readonly string _fallbackUrl;
+    private readonly HttpStatusCode _statusCode;
+
+    public BackResult(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) =>
+        (_fallbackUrl, _statusCode) = (fallbackUrl ?? "/", statusCode);
+
+    public Task ExecuteResultAsync(ActionContext context)
+    {
+        var referrer = context.HttpContext.Request.Headers.Referer.ToString();
+        var redirectUrl = !string.IsNullOrEmpty(referrer) ? referrer : _fallbackUrl;
+
+        context.HttpContext.Response.StatusCode = (int)_statusCode;
+        context.HttpContext.Response.Headers.Location = redirectUrl;
+
+        return Task.CompletedTask;
+    }
+}

InertiaCoreTests/UnitTestBack.cs

@@ -0,0 +1,174 @@
+using System.Net;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Abstractions;
+using Microsoft.AspNetCore.Routing;
+using Moq;
+
+namespace InertiaCoreTests;
+
+public partial class Tests
+{
+    [Test]
+    [Description("Test Back function with Inertia request returns redirect status with location header.")]
+    public async Task TestBackWithInertiaRequest()
+    {
+        var backResult = _factory.Back("/fallback");
+
+        var headers = new HeaderDictionary
+        {
+            { "X-Inertia", "true" }
+        };
+
+        var responseHeaders = new HeaderDictionary();
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupProperty(r => r.StatusCode);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        await backResult.ExecuteResultAsync(context);
+
+        // Should set status code to 303 (SeeOther) and location header to fallback URL
+        Assert.That(response.Object.StatusCode, Is.EqualTo(303));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/fallback"));
+    }
+
+    [Test]
+    [Description("Test Back function with regular request and referrer header redirects to referrer.")]
+    public async Task TestBackWithReferrerHeader()
+    {
+        var backResult = _factory.Back("/fallback");
+
+        var headers = new HeaderDictionary
+        {
+            { "Referer", "https://example.com/previous-page" }
+        };
+
+        var responseHeaders = new HeaderDictionary();
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupProperty(r => r.StatusCode);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        var result = backResult as IActionResult;
+        Assert.That(result, Is.Not.Null);
+
+        await result.ExecuteResultAsync(context);
+
+        // Should set status code to 303 (SeeOther) and location header to referrer
+        Assert.That(response.Object.StatusCode, Is.EqualTo(303));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("https://example.com/previous-page"));
+    }
+
+    [Test]
+    [Description("Test Back function without referrer uses fallback URL.")]
+    public async Task TestBackWithFallbackUrl()
+    {
+        var backResult = _factory.Back("/custom-fallback");
+
+        var headers = new HeaderDictionary();
+
+        var responseHeaders = new HeaderDictionary();
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupProperty(r => r.StatusCode);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        var result = backResult as IActionResult;
+        Assert.That(result, Is.Not.Null);
+
+        await result.ExecuteResultAsync(context);
+
+        // Should set status code to 303 (SeeOther) and location header to custom fallback
+        Assert.That(response.Object.StatusCode, Is.EqualTo(303));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/custom-fallback"));
+    }
+
+    [Test]
+    [Description("Test Back function without fallback URL uses default root path.")]
+    public async Task TestBackWithDefaultFallback()
+    {
+        var backResult = _factory.Back();
+
+        var headers = new HeaderDictionary();
+
+        var responseHeaders = new HeaderDictionary();
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupProperty(r => r.StatusCode);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        var result = backResult as IActionResult;
+        Assert.That(result, Is.Not.Null);
+
+        await result.ExecuteResultAsync(context);
+
+        // Should set status code to 303 (SeeOther) and location header to default fallback
+        Assert.That(response.Object.StatusCode, Is.EqualTo(303));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/"));
+    }
+
+    [Test]
+    [Description("Test Back function with permanent redirect.")]
+    public async Task TestBackWithPermanentRedirect()
+    {
+        var backResult = _factory.Back("/fallback", HttpStatusCode.MovedPermanently);
+
+        var headers = new HeaderDictionary();
+
+        var responseHeaders = new HeaderDictionary();
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupProperty(r => r.StatusCode);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        var result = backResult as IActionResult;
+        Assert.That(result, Is.Not.Null);
+
+        await result.ExecuteResultAsync(context);
+
+        // Should set status code to 301 (MovedPermanently) and location header to fallback
+        Assert.That(response.Object.StatusCode, Is.EqualTo(301));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/fallback"));
+    }
+}