[1.x] Add custom JSON serializer (#27)

* Implement custom JSON serializer configuration

* Add custom JSON serializer to README

* Remove unused imports

Author: kapi2289

InertiaCore/Extensions/Configure.cs

@@ -7,6 +7,7 @@
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
 
 namespace InertiaCore.Extensions;
 
@@ -48,6 +49,7 @@ public static IServiceCollection AddInertia(this IServiceCollection services,
 
         services.AddSingleton<IResponseFactory, ResponseFactory>();
         services.AddSingleton<IGateway, Gateway>();
+        services.AddSingleton<IInertiaSerializer, DefaultInertiaSerializer>();
 
         services.Configure<MvcOptions>(mvcOptions => { mvcOptions.Filters.Add<InertiaActionFilter>(); });
 
@@ -56,6 +58,16 @@ public static IServiceCollection AddInertia(this IServiceCollection services,
         return services;
     }
 
+    public static IServiceCollection UseInertiaSerializer<TImplementation>(this IServiceCollection services)
+        where TImplementation : IInertiaSerializer
+    {
+        services.Replace(
+            new ServiceDescriptor(typeof(IInertiaSerializer), typeof(TImplementation), ServiceLifetime.Singleton)
+        );
+
+        return services;
+    }
+
     public static IServiceCollection AddViteHelper(this IServiceCollection services,
         Action<ViteOptions>? options = null)
     {

InertiaCore/Response.cs

@@ -1,5 +1,3 @@
-using System.Text.Json;
-using System.Text.Json.Serialization;
 using InertiaCore.Extensions;
 using InertiaCore.Models;
 using InertiaCore.Props;
@@ -16,13 +14,15 @@ public class Response : IActionResult
     private readonly Dictionary<string, object?> _props;
     private readonly string _rootView;
     private readonly string? _version;
+    private readonly IInertiaSerializer _serializer;
 
     private ActionContext? _context;
     private Page? _page;
     private IDictionary<string, object>? _viewData;
 
-    internal Response(string component, Dictionary<string, object?> props, string rootView, string? version)
-        => (_component, _props, _rootView, _version) = (component, props, rootView, version);
+    internal Response(string component, Dictionary<string, object?> props, string rootView, string? version,
+        IInertiaSerializer serializer)
+        => (_component, _props, _rootView, _version, _serializer) = (component, props, rootView, version, serializer);
 
     public async Task ExecuteResultAsync(ActionContext context)
     {
@@ -172,11 +172,7 @@ protected internal JsonResult GetJson()
         _context!.HttpContext.Response.Headers.Override("Vary", "Accept");
         _context!.HttpContext.Response.StatusCode = 200;
 
-        return new JsonResult(_page, new JsonSerializerOptions
-        {
-            PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
-            ReferenceHandler = ReferenceHandler.IgnoreCycles
-        });
+        return _serializer.SerializeResult(_page);
     }
 
     private ViewResult GetView()

InertiaCore/ResponseFactory.cs

@@ -1,6 +1,4 @@
 using System.Net;
-using System.Text.Json;
-using System.Text.Json.Serialization;
 using InertiaCore.Models;
 using InertiaCore.Props;
 using InertiaCore.Ssr;
@@ -33,12 +31,14 @@ internal class ResponseFactory : IResponseFactory
 {
     private readonly IHttpContextAccessor _contextAccessor;
     private readonly IGateway _gateway;
+    private readonly IInertiaSerializer _serializer;
     private readonly IOptions<InertiaOptions> _options;
 
     private object? _version;
 
-    public ResponseFactory(IHttpContextAccessor contextAccessor, IGateway gateway, IOptions<InertiaOptions> options) =>
-        (_contextAccessor, _gateway, _options) = (contextAccessor, gateway, options);
+    public ResponseFactory(IHttpContextAccessor contextAccessor, IGateway gateway, IInertiaSerializer serializer,
+        IOptions<InertiaOptions> options)
+        => (_contextAccessor, _gateway, _serializer, _options) = (contextAccessor, gateway, serializer, options);
 
     public Response Render(string component, object? props = null)
     {
@@ -50,7 +50,7 @@ public Response Render(string component, object? props = null)
                 .ToDictionary(o => o.Name, o => o.GetValue(props))
         };
 
-        return new Response(component, dictProps, _options.Value.RootView, GetVersion());
+        return new Response(component, dictProps, _options.Value.RootView, GetVersion(), _serializer);
     }
 
     public async Task<IHtmlContent> Head(dynamic model)
@@ -84,13 +84,7 @@ public async Task<IHtmlContent> Html(dynamic model)
             }
         }
 
-        var data = JsonSerializer.Serialize(model,
-            new JsonSerializerOptions
-            {
-                PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
-                ReferenceHandler = ReferenceHandler.IgnoreCycles
-            });
-
+        var data = _serializer.Serialize(model);
         var encoded = WebUtility.HtmlEncode(data);
 
         return new HtmlString($"<div id=\"app\" data-page=\"{encoded}\"></div>");

InertiaCore/Ssr/Gateway.cs

@@ -1,7 +1,6 @@
 using System.Net.Http.Json;
 using System.Text;
-using System.Text.Json;
-using System.Text.Json.Serialization;
+using InertiaCore.Utils;
 
 namespace InertiaCore.Ssr;
 
@@ -13,17 +12,14 @@ internal interface IGateway
 internal class Gateway : IGateway
 {
     private readonly IHttpClientFactory _httpClientFactory;
+    private readonly IInertiaSerializer _serializer;
 
-    public Gateway(IHttpClientFactory httpClientFactory) => _httpClientFactory = httpClientFactory;
+    public Gateway(IHttpClientFactory httpClientFactory, IInertiaSerializer serializer)
+        => (_httpClientFactory, _serializer) = (httpClientFactory, serializer);
 
     public async Task<SsrResponse?> Dispatch(dynamic model, string url)
     {
-        var json = JsonSerializer.Serialize(model,
-            new JsonSerializerOptions
-            {
-                PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
-                ReferenceHandler = ReferenceHandler.IgnoreCycles
-            });
+        var json = _serializer.Serialize(model);
         var content = new StringContent(json.ToString(), Encoding.UTF8, "application/json");
 
         var client = _httpClientFactory.CreateClient();

InertiaCore/Utils/DefaultInertiaSerializer.cs

@@ -0,0 +1,27 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using Microsoft.AspNetCore.Mvc;
+
+namespace InertiaCore.Utils;
+
+public class DefaultInertiaSerializer : IInertiaSerializer
+{
+    protected static JsonSerializerOptions GetOptions()
+    {
+        return new JsonSerializerOptions
+        {
+            PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+            ReferenceHandler = ReferenceHandler.IgnoreCycles
+        };
+    }
+
+    public string Serialize(object? obj)
+    {
+        return JsonSerializer.Serialize(obj, GetOptions());
+    }
+
+    public JsonResult SerializeResult(object? obj)
+    {
+        return new JsonResult(obj, GetOptions());
+    }
+}

InertiaCore/Utils/IInertiaSerializer.cs

@@ -0,0 +1,10 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace InertiaCore.Utils;
+
+public interface IInertiaSerializer
+{
+    public string Serialize(object? obj);
+
+    public JsonResult SerializeResult(object? obj);
+}

InertiaCoreTests/Setup.cs

@@ -22,11 +22,12 @@ public void Setup()
         var contextAccessor = new Mock<IHttpContextAccessor>();
         var httpClientFactory = new Mock<IHttpClientFactory>();
 
-        var gateway = new Gateway(httpClientFactory.Object);
+        var serializer = new DefaultInertiaSerializer();
+        var gateway = new Gateway(httpClientFactory.Object, serializer);
         var options = new Mock<IOptions<InertiaOptions>>();
         options.SetupGet(x => x.Value).Returns(new InertiaOptions());
 
-        _factory = new ResponseFactory(contextAccessor.Object, gateway, options.Object);
+        _factory = new ResponseFactory(contextAccessor.Object, gateway, serializer, options.Object);
     }
 
     /// <summary>

InertiaCoreTests/UnitTestConfiguration.cs

@@ -9,6 +9,10 @@
 
 namespace InertiaCoreTests;
 
+internal class DummySerializer : DefaultInertiaSerializer
+{
+}
+
 public partial class Tests
 {
     [Test]
@@ -28,6 +32,7 @@ public void TestConfiguration()
 
             Assert.That(builder.Services.Any(s => s.ServiceType == typeof(IResponseFactory)), Is.True);
             Assert.That(builder.Services.Any(s => s.ServiceType == typeof(IGateway)), Is.True);
+            Assert.That(builder.Services.Any(s => s.ServiceType == typeof(IInertiaSerializer)), Is.True);
         });
 
         var mvcConfiguration =
@@ -45,4 +50,30 @@ public void TestConfiguration()
 
         Assert.DoesNotThrow(() => Inertia.GetVersion());
     }
+
+    [Test]
+    [Description("Test if the configuration registers properly custom JSON serializer.")]
+    public void TestSerializerConfiguration()
+    {
+        var builder = WebApplication.CreateBuilder();
+        builder.Services.AddInertia();
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(builder.Services.Any(s => s.ServiceType == typeof(IInertiaSerializer)), Is.True);
+
+            Assert.That(builder.Services.Any(s => s.ImplementationType == typeof(DefaultInertiaSerializer)), Is.True);
+            Assert.That(builder.Services.Any(s => s.ImplementationType == typeof(DummySerializer)), Is.False);
+        });
+
+        Assert.DoesNotThrow(() => builder.Services.UseInertiaSerializer<DummySerializer>());
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(builder.Services.Any(s => s.ServiceType == typeof(IInertiaSerializer)), Is.True);
+
+            Assert.That(builder.Services.Any(s => s.ImplementationType == typeof(DefaultInertiaSerializer)), Is.False);
+            Assert.That(builder.Services.Any(s => s.ImplementationType == typeof(DummySerializer)), Is.True);
+        });
+    }
 }

README.md

@@ -217,6 +217,73 @@ builder.Services.AddInertia(options =>
 });
 ```
 
+### Custom JSON serializer
+
+You can use a custom JSON serializer in your app by creating a custom class implementing the `IInertiaSerializer`
+interface:
+
+```csharp
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using Microsoft.AspNetCore.Mvc;
+
+public class CustomSerializer : IInertiaSerializer
+{
+    // Used in HTML responses
+    public string Serialize(object? obj)
+    {
+        // Default serialization
+        return JsonSerializer.Serialize(obj, new JsonSerializerOptions
+        {
+            PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+            ReferenceHandler = ReferenceHandler.IgnoreCycles
+        });
+    }
+
+    // Used in JSON responses
+    public JsonResult SerializeResult(object? obj)
+    {
+        // Default serialization
+        return new JsonResult(obj, new JsonSerializerOptions
+        {
+            PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+            ReferenceHandler = ReferenceHandler.IgnoreCycles
+        });
+    }
+}
+```
+
+or extending the `DefaultInertiaSerializer` class, which also implements the `IInertiaSerializer` interface:
+
+```csharp
+public class CustomSerializer : DefaultInertiaSerializer
+{
+    protected new static JsonSerializerOptions GetOptions()
+    {
+        // Default options
+        return new JsonSerializerOptions
+        {
+            PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+            ReferenceHandler = ReferenceHandler.IgnoreCycles
+        };
+    }
+}
+```
+
+You can then register it in the configuration:
+
+```csharp
+builder.Services.AddInertia();
+
+[...]
+
+builder.Services.UseInertiaSerializer<CustomSerializer>();
+
+[...]
+
+app.UseInertia();
+```
+
 ### Vite Helper
 
 A Vite helper class is available to automatically load your generated styles or scripts by simply using the `@Vite.Input("src/main.tsx")` helper. You can also enable HMR when using React by using the `@Vite.ReactRefresh()` helper. This pairs well with the `laravel-vite-plugin` npm package.