Added Error Handling

API/Controllers/BaseApiController.cs

@@ -0,0 +1,11 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace API.Controllers
+{
+    [ApiController]
+    [Route("api/[controller]")]
+    public class BaseApiController : ControllerBase
+    {
+        
+    }
+}

API/Controllers/BuggyController.cs

@@ -0,0 +1,47 @@
+using API.Errors;
+using Infrastructure.Data;
+using Microsoft.AspNetCore.Mvc;
+
+namespace API.Controllers
+{
+    public class BuggyController : BaseApiController
+    {
+        private readonly StoreContext _context;
+        public BuggyController(StoreContext context)
+        {
+            _context = context;
+        }
+
+        [HttpGet("notfound")]
+        public ActionResult GetNotFoundRequest()
+        {
+            var thing = _context.Products.Find(42);
+            if (thing == null)
+            {
+                return NotFound(new ApiResponse(404));
+            }
+            
+            return Ok();
+        }
+
+        [HttpGet("servererror")]
+        public ActionResult GetServerError()
+        {
+            var thing = _context.Products.Find(42);
+            var thingToReturn =  thing.ToString();
+            return Ok();
+        }
+
+        [HttpGet("badrequest")]
+        public ActionResult GetBadRequest()
+        {
+            return BadRequest(new ApiResponse(400));
+        }
+
+        [HttpGet("badrequest/{id}")]
+        public ActionResult GetNotFoundRequest(int id)
+        {
+            return Ok();
+        }
+    }
+}

API/Controllers/ErrorController.cs

@@ -0,0 +1,14 @@
+using API.Errors;
+using Microsoft.AspNetCore.Mvc;
+
+namespace API.Controllers
+{
+    [Route("errors/{code}")]
+    public class ErrorController : BaseApiController
+    {
+        public IActionResult Error(int code)
+        {
+            return new ObjectResult(new ApiResponse(code));
+        }
+    }
+}

API/Controllers/ProductsController.cs

@@ -7,9 +7,7 @@ using AutoMapper;
 
 namespace API.Controllers
 {
-    [ApiController]
-    [Route("api/[controller]")]
-    public class ProductsController : ControllerBase 
+    public class ProductsController : BaseApiController
     {
         private readonly IGenericRepository<Product> _productsRepo;
         private readonly IGenericRepository<ProductBrand> _productBrandRepo;

API/Errors/ApiException.cs

@@ -0,0 +1,12 @@
+namespace API.Errors
+{
+    public class ApiException : ApiResponse
+    {
+        public ApiException(int statusCode, string message = null, string details = null) : base(statusCode, message)
+        {
+            Details = details;
+        }
+
+        public string Details { get; set; }
+    }
+}

API/Errors/ApiResponse.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace API.Errors
+{
+    public class ApiResponse
+    {
+        public ApiResponse(int statusCode, string message = null)
+        {
+            StatusCode = statusCode;
+            Message = message ?? GetDefaultMessageForStatusCode(statusCode);
+        }
+
+        public int StatusCode { get; set; }
+        public string Message { get; set; }
+
+        private string GetDefaultMessageForStatusCode(int statusCode)
+        {
+           return statusCode switch
+           {
+               400 => "A bad request, you have made",
+               401 => "Authorized, you are not",
+               404 => "Resource found, it was not",
+               500 => "Errors are the path to the dark side. Errors lead to anger. Anger leads to hate. Hate leads to career change",
+               _ => null
+           };
+        }
+    }
+}

API/Middleware/ExceptionMiddleware.cs

@@ -0,0 +1,39 @@
+using System.Net;
+using System.Text.Json;
+using API.Errors;
+
+namespace API.Middleware
+{
+    public class ExceptionMiddleware
+    {
+        private readonly RequestDelegate _next;
+        private readonly ILogger<ExceptionMiddleware> _logger;
+        private readonly IHostEnvironment _env;
+        public ExceptionMiddleware(RequestDelegate next, ILogger<ExceptionMiddleware> logger, IHostEnvironment env)
+        {
+            _env = env;
+            _logger = logger;
+            _next = next;
+        }
+
+        public async Task InvokeAsync(HttpContext context)
+        {
+            try
+            {
+                await _next(context);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, ex.Message);
+                context.Response.ContentType = "application/json";
+                context.Response.StatusCode = (int)HttpStatusCode.InternalServerError;
+                var response = _env.IsDevelopment()
+                    ? new ApiException((int)HttpStatusCode.InternalServerError, ex.Message, ex.StackTrace.ToString())
+                    : new ApiException((int)HttpStatusCode.InternalServerError);
+                var options = new JsonSerializerOptions{PropertyNamingPolicy = JsonNamingPolicy.CamelCase};
+                var json = JsonSerializer.Serialize(response, options);
+                await context.Response.WriteAsync(json);
+            }
+        }
+    }
+}

API/Startup.cs

@@ -1,4 +1,5 @@
 using API.Helpers;
+using API.Middleware;
 using Core.Interfaces;
 using Infrastructure.Data;
 using Microsoft.EntityFrameworkCore;
@@ -33,16 +34,20 @@ namespace API
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
         public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
         {
+            app.UseMiddleware<ExceptionMiddleware>();
+            
             if (env.IsDevelopment())
             {
-                app.UseDeveloperExceptionPage();
                 app.UseSwagger();
                 app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/v1/swagger.json", "WebAPIv5 v1"));
             }
 
+            app.UseStatusCodePagesWithReExecute("/errors/{0}");
+
             app.UseHttpsRedirection();
 
             app.UseRouting();
+            app.UseStaticFiles();
 
             app.UseAuthorization();