Refactor API response filter and helper.

Author: imclint21

src/Initium/Attributes/ApiResponseAttribute.cs

@@ -5,20 +5,12 @@ namespace Initium.Attributes;
 
 [SuppressMessage("ReSharper", "UnusedMember.Global")]
 [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, AllowMultiple = true)]
-public class ApiResponseAttribute : Attribute
+public class ApiResponseAttribute(HttpStatusCode statusCode, string message) : Attribute
 {
-	public int StatusCode { get; }
-	public string Message { get; }
+	public HttpStatusCode StatusCode { get; } = statusCode;
+	public string Message { get; } = message;
 
-	public ApiResponseAttribute(HttpStatusCode statusCode, string message)
+	public ApiResponseAttribute(int statusCode, string message) : this((HttpStatusCode)statusCode, message)
 	{
-		StatusCode = (int)statusCode;
-		Message = message;
-	}
-
-	public ApiResponseAttribute(int statusCode, string message)
-	{
-		StatusCode = statusCode;
-		Message = message;
 	}
 }

src/Initium/Attributes/ValidateModelAttribute.cs

@@ -1,7 +1,7 @@
 using System.Diagnostics.CodeAnalysis;
+using System.Net;
 using FluentValidation;
 using Initium.Response;
-using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc.Filters;
 
 namespace Initium.Attributes;
@@ -32,7 +32,7 @@ public void OnActionExecuting(ActionExecutingContext context)
 		context.Result = ApiResponseBuilder
 			.CreateFromContext(context.HttpContext)
 			.WithMessage("One or more validation errors occurred.")
-			.WithStatusCode(StatusCodes.Status400BadRequest)
+			.WithStatusCode(HttpStatusCode.BadRequest)
 			.WithErrors(validationResult.Errors)
 			.BuildAsJsonResult();
 	}

src/Initium/Filters/ApiExceptionFilter.cs

@@ -26,17 +26,17 @@ public void OnException(ExceptionContext context)
 		{
 			ApiException ex => apiResponseBuilder
 				.WithMessage(ex.Message)
-				.WithStatusCode((int)ex.StatusCode)
+				.WithStatusCode(ex.StatusCode)
 				.BuildAsJsonResult(),
 
 			NotImplementedException ex => apiResponseBuilder
 				.WithMessage(ex.Message)
-				.WithStatusCode((int)HttpStatusCode.NotImplemented)
+				.WithStatusCode(HttpStatusCode.NotImplemented)
 				.BuildAsJsonResult(),
 
 			_ => apiResponseBuilder
 				.WithMessage("An unexpected error occurred.")
-				.WithStatusCode((int)HttpStatusCode.InternalServerError)
+				.WithStatusCode(HttpStatusCode.InternalServerError)
 				.BuildAsJsonResult()
 		};
 

src/Initium/Filters/ApiResponseFilter.cs

@@ -1,15 +1,17 @@
+using System.Net;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Filters;
 using Initium.Helpers;
 using Initium.Response;
 using Initium.Results;
+using Microsoft.Extensions.Logging;
 
 namespace Initium.Filters;
 
 /// <summary>
 /// Filter responsible for transforming <see cref="ServiceResult"/> objects into a standardized <see cref="ApiResponse"/>.
 /// </summary>
-internal class ApiResponseFilter : ActionFilterAttribute
+internal class ApiResponseFilter(ILogger<ApiResponseFilter> logger) : ActionFilterAttribute
 {
     /// <summary>
     /// Called after the action executed, and transforms <see cref="ServiceResult"/> into a standardized <see cref="ApiResponse"/>.
@@ -18,26 +20,34 @@ internal class ApiResponseFilter : ActionFilterAttribute
     public override void OnActionExecuted(ActionExecutedContext context)
     {
         // Check if the result of the action is an ObjectResult containing a ServiceResult.
-        if (context.Result is not ObjectResult { Value: ServiceResult serviceResult }) 
-            return;
+        if (context.Result is not ObjectResult { Value: ServiceResult serviceResult }) return;
+ 
+        // Determine the HTTP status code:
+		// 1. Use ServiceResult status code if set.
+		// 2. Otherwise, use the default based on the HTTP method.
+        var statusCode = 
+	        serviceResult.StatusCode 
+	        ?? ApiResponseHelper.GetDefaultStatusCode(context.HttpContext);
 
-        // Extract API response attributes from the current action descriptor (method or controller level).
-        var actionDescriptor = context.ActionDescriptor;
-        var apiResponseAttributes = ApiResponseHelper.GetApiResponseAttributes(actionDescriptor);
-
-        var statusCode = (int?)serviceResult.StatusCode ?? context.HttpContext.Response.StatusCode;
+		// Determine the response message:
+		// 1. Use ServiceResult message if set.
+		// 2. Otherwise, get the message from [ApiResponse] attributes.
+		// 3. If none found, use the default message for the StatusCode.
+        var message = 
+	        serviceResult.Message 
+	        ?? GetApiResponseMessage(context, statusCode)
+	        ?? ApiResponseHelper.GetDefaultMessageForStatusCode(statusCode);
 
-        // Find the matching ApiResponseAttribute based on the HTTP status code.
-        var matchingAttribute = apiResponseAttributes.FirstOrDefault(attribute =>
-            attribute.StatusCode == statusCode);
-
         // Create an ApiResponse object, including HTTP context details.
         context.Result = ApiResponseBuilder
             .CreateFromContext(context.HttpContext)
             .WithStatusCode(statusCode)
-            .WithMessage(serviceResult.Message 
-                         ?? matchingAttribute?.Message 
-                         ?? ApiResponseHelper.GetDefaultMessageForStatusCode(statusCode))
+            .WithMessage(message)
+            // .WithData(serviceResult.Data)
+            .WithCustomHeaders(serviceResult.Metadata)
             .BuildAsJsonResult();
     }
+
+    private static string? GetApiResponseMessage(ActionExecutedContext context, HttpStatusCode statusCode) => 
+        ApiResponseHelper.GetApiResponseAttributes(context.ActionDescriptor).FirstOrDefault(attribute => attribute.StatusCode == statusCode)?.Message;
 }

src/Initium/Filters/ImplicitValidationFilter.cs

@@ -1,7 +1,7 @@
+using System.Net;
 using FluentValidation;
 using Initium.Infrastructure;
 using Initium.Response;
-using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc.Filters;
 
 namespace Initium.Filters;
@@ -36,7 +36,7 @@ public void OnActionExecuting(ActionExecutingContext context)
         context.Result = ApiResponseBuilder
             .CreateFromContext(context.HttpContext)
             .WithMessage("One or more validation errors occurred.")
-            .WithStatusCode(StatusCodes.Status400BadRequest)
+            .WithStatusCode(HttpStatusCode.BadRequest)
             .WithErrors(validationResult.Errors)
             .BuildAsJsonResult();
     }

src/Initium/Helpers/ApiResponseHelper.cs

@@ -1,6 +1,8 @@
+using System.Net;
 using Microsoft.AspNetCore.Mvc.Abstractions;
 using Microsoft.AspNetCore.Mvc.Controllers;
 using Initium.Attributes;
+using Microsoft.AspNetCore.Http;
 
 namespace Initium.Helpers;
 
@@ -41,17 +43,24 @@ public static IEnumerable<ApiResponseAttribute> GetApiResponseAttributes(ActionD
     /// A string containing the default message associated with the status code.
     /// If the status code is unrecognized, a generic internal server error message is returned.
     /// </returns>
-    public static string GetDefaultMessageForStatusCode(int statusCode) => statusCode switch
+    public static string GetDefaultMessageForStatusCode(HttpStatusCode statusCode) => statusCode switch
     {
-        200 => "The operation completed successfully.",
-        201 => "The resource was created successfully.",
-        204 => "The request was successful, but there is no content to return.",
-        400 => "One or more validation errors occurred.",
-        401 => "Access is denied due to invalid credentials",
-        403 => "Access is forbidden, you do not have the necessary permissions to perform this operation.",
-        404 => "The requested resource could not be found.",
-        409 => "A conflict occurred, the request could not be completed due to conflicting changes.",
-        503 => "The service is currently unavailable.",
+        HttpStatusCode.OK => "The operation completed successfully.",
+        HttpStatusCode.Created => "The resource was created successfully.",
+        HttpStatusCode.NoContent => "The request was successful, but there is no content to return.",
+        HttpStatusCode.BadRequest => "One or more validation errors occurred.",
+        HttpStatusCode.Unauthorized => "Access is denied due to invalid credentials.",
+        HttpStatusCode.Forbidden => "Access is forbidden, you do not have the necessary permissions to perform this operation.",
+        HttpStatusCode.NotFound => "The requested resource could not be found.",
+        HttpStatusCode.Conflict => "A conflict occurred, the request could not be completed due to conflicting changes.",
+        HttpStatusCode.ServiceUnavailable => "The service is currently unavailable.",
         _ => "An internal server error occurred."
     };
+    
+    public static HttpStatusCode GetDefaultStatusCode(HttpContext context) => context.Request.Method.ToUpper() switch
+    {
+        "POST" => HttpStatusCode.Created,
+        "DELETE" => HttpStatusCode.NoContent,
+        _ => (HttpStatusCode)context.Response.StatusCode
+    };
 }

src/Initium/Response/ApiResponseBuilder.cs

@@ -1,7 +1,9 @@
 using System.Diagnostics.CodeAnalysis;
+using System.Net;
 using FluentValidation.Results;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
 
 namespace Initium.Response;
 
@@ -59,9 +61,9 @@ public ApiResponseBuilder WithMessage(string message)
     /// </summary>
     /// <param name="statusCode">The HTTP status code to include in the response.</param>
     /// <returns>The current instance of the <see cref="ApiResponseBuilder"/>.</returns>
-    public ApiResponseBuilder WithStatusCode(int statusCode)
+    public ApiResponseBuilder WithStatusCode(HttpStatusCode statusCode)
     {
-        _apiResponse.StatusCode = statusCode;
+        _apiResponse.StatusCode = (int)statusCode;
         return this;
     }
 

src/Initium/Results/InvalidModelStateResult.cs

@@ -19,7 +19,7 @@ public InvalidModelStateResult(ActionContext actionContext) : base(actionContext
 		StatusCode = StatusCodes.Status400BadRequest;
 		Value = ApiResponseBuilder.CreateFromContext(actionContext.HttpContext)
 			.WithMessage("One or more validation errors occurred.")
-			.WithStatusCode(StatusCodes.Status400BadRequest)
+			.WithStatusCode(HttpStatusCode.BadRequest)
 			.Build();
 	}
 }

src/Initium/Results/ServiceResult.cs

@@ -25,7 +25,7 @@ public class ServiceResult : BaseResult
     /// <param name="message">An optional message describing the result.</param>
     /// <param name="statusCode">The HTTP status code associated with the result. Defaults to <see cref="HttpStatusCode.OK"/>.</param>
     /// <returns>A successful <see cref="ServiceResult"/>.</returns>
-    public static ServiceResult Ok(string? message = null, HttpStatusCode statusCode = HttpStatusCode.OK) => new()
+    public static ServiceResult Ok(string? message = null, HttpStatusCode? statusCode = null) => new()
     {
         Success = true,
         Message = message,
@@ -49,7 +49,7 @@ public class ServiceResult : BaseResult
     /// <param name="message">An optional message describing the error.</param>
     /// <param name="statusCode">The HTTP status code associated with the error. Defaults to <see cref="HttpStatusCode.BadRequest"/>.</param>
     /// <returns>A failed <see cref="ServiceResult"/>.</returns>
-    public static ServiceResult Error(string? message = null, HttpStatusCode statusCode = HttpStatusCode.BadRequest) => new()
+    public static ServiceResult Error(string? message = null, HttpStatusCode? statusCode = null) => new()
     {
         Success = false,
         Message = message,
@@ -101,7 +101,7 @@ public ServiceResult WithStatusCode(HttpStatusCode statusCode)
 
     public ServiceResult WithMetadata(string key, string value)
     {
-        Metadata ??= new Dictionary<string, string>();
+        // Metadata ??= new Dictionary<string, string>();
         Metadata[key] = value;
         return this;
     }
@@ -149,7 +149,7 @@ public class ServiceResult<TData> : ServiceResult
     /// <param name="message">An optional message describing the result.</param>
     /// <param name="statusCode">The HTTP status code associated with the result. Defaults to <see cref="HttpStatusCode.OK"/>.</param>
     /// <returns>A successful <see cref="ServiceResult{TData}"/>.</returns>
-    public static ServiceResult<TData> Ok(TData data, string? message = null, HttpStatusCode statusCode = HttpStatusCode.OK) => new()
+    public static ServiceResult<TData> Ok(TData data, string? message = null, HttpStatusCode? statusCode = null) => new()
     {
         Success = true,
         Data = data,
@@ -163,7 +163,7 @@ public class ServiceResult<TData> : ServiceResult
     /// <param name="data">The data returned by the operation.</param>
     /// <param name="statusCode">The HTTP status code associated with the result.</param>
     /// <returns>A successful <see cref="ServiceResult{TData}"/>.</returns>
-    public static ServiceResult<TData> Ok(TData data, HttpStatusCode statusCode) => new()
+    public static ServiceResult<TData> Ok(TData data, HttpStatusCode? statusCode = null) => new()
     {
         Success = true,
         Data = data,
@@ -176,7 +176,7 @@ public class ServiceResult<TData> : ServiceResult
     /// <param name="message">An optional message describing the error.</param>
     /// <param name="statusCode">The HTTP status code associated with the error. Defaults to <see cref="HttpStatusCode.BadRequest"/>.</param>
     /// <returns>A failed <see cref="ServiceResult{TData}"/>.</returns>
-    public new static ServiceResult<TData> Error(string? message = null, HttpStatusCode statusCode = HttpStatusCode.BadRequest) => new()
+    public new static ServiceResult<TData> Error(string? message = null, HttpStatusCode? statusCode = null) => new()
     {
         Success = false,
         Message = message,