From 0ad50629d522e66bb537706f3114e188f987edee Mon Sep 17 00:00:00 2001
From: "Collin M. Barrett" <collinbarrett@users.noreply.github.com>
Date: Fri, 12 Nov 2021 18:21:30 -0600
Subject: [PATCH] =?UTF-8?q?feat(dir):=20=E2=9C=A8=20validate=20list=20deta?=
 =?UTF-8?q?ils=20query=20id?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../FilterLists.Directory.Api.csproj          |  1 +
 .../ProblemDetailsConfigurationExtensions.cs  | 29 +++++++++++++++++++
 .../FilterLists.Directory.Api/Program.cs      |  5 ++++
 ...s.cs => SwaggerConfigurationExtensions.cs} |  2 +-
 .../ConfigurationExtensions.cs                |  3 ++
 .../FilterLists.Directory.Application.csproj  |  1 +
 .../Queries/GetListDetails.cs                 | 10 +++++++
 .../ValidatorPipelineBahavior.cs              | 27 +++++++++++++++++
 8 files changed, 77 insertions(+), 1 deletion(-)
 create mode 100644 services/Directory/FilterLists.Directory.Api/ProblemDetailsConfigurationExtensions.cs
 rename services/Directory/FilterLists.Directory.Api/{SwaggerExtensions.cs => SwaggerConfigurationExtensions.cs} (96%)
 create mode 100644 services/Directory/FilterLists.Directory.Application/ValidatorPipelineBahavior.cs

diff --git a/services/Directory/FilterLists.Directory.Api/FilterLists.Directory.Api.csproj b/services/Directory/FilterLists.Directory.Api/FilterLists.Directory.Api.csproj
index 59a959eb7..69ab728f6 100644
--- a/services/Directory/FilterLists.Directory.Api/FilterLists.Directory.Api.csproj
+++ b/services/Directory/FilterLists.Directory.Api/FilterLists.Directory.Api.csproj
@@ -28,6 +28,7 @@
   </ItemGroup>
 
   <ItemGroup>
+    <PackageReference Include="Hellang.Middleware.ProblemDetails" Version="6.2.0" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="6.0.0">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
diff --git a/services/Directory/FilterLists.Directory.Api/ProblemDetailsConfigurationExtensions.cs b/services/Directory/FilterLists.Directory.Api/ProblemDetailsConfigurationExtensions.cs
new file mode 100644
index 000000000..427447d6d
--- /dev/null
+++ b/services/Directory/FilterLists.Directory.Api/ProblemDetailsConfigurationExtensions.cs
@@ -0,0 +1,29 @@
+using FluentValidation;
+using Hellang.Middleware.ProblemDetails;
+
+namespace FilterLists.Directory.Api;
+
+internal static class ProblemDetailsConfigurationExtensions
+{
+    public static void ConfigureProblemDetails(this ProblemDetailsOptions options)
+    {
+        options.MapFluentValidationException();
+        options.MapToStatusCode<NotImplementedException>(StatusCodes.Status501NotImplemented);
+        options.MapToStatusCode<HttpRequestException>(StatusCodes.Status503ServiceUnavailable);
+        options.MapToStatusCode<Exception>(StatusCodes.Status500InternalServerError);
+    }
+
+    private static void MapFluentValidationException(this ProblemDetailsOptions options)
+    {
+        options.Map<ValidationException>((ctx, ex) =>
+        {
+            var factory = ctx.RequestServices.GetRequiredService<ProblemDetailsFactory>();
+            var errors = ex.Errors
+                .GroupBy(f => f.PropertyName)
+                .ToDictionary(
+                    g => g.Key,
+                    g => g.Select(f => f.ErrorMessage).ToArray());
+            return factory.CreateValidationProblemDetails(ctx, errors);
+        });
+    }
+}
diff --git a/services/Directory/FilterLists.Directory.Api/Program.cs b/services/Directory/FilterLists.Directory.Api/Program.cs
index 49a099233..398c5ea67 100644
--- a/services/Directory/FilterLists.Directory.Api/Program.cs
+++ b/services/Directory/FilterLists.Directory.Api/Program.cs
@@ -3,13 +3,17 @@
 using FilterLists.Directory.Application;
 using FilterLists.Directory.Infrastructure.Persistence;
 using FilterLists.SharedKernel.Logging;
+using Hellang.Middleware.ProblemDetails;
+using Hellang.Middleware.ProblemDetails.Mvc;
 
 var builder = WebApplication.CreateBuilder(args);
 
 builder.Host.ConfigureApplication();
 builder.Services.AddMemoryCache();
+builder.Services.AddProblemDetails(ProblemDetailsConfigurationExtensions.ConfigureProblemDetails);
 builder.Services.Configure<RouteOptions>(options => options.LowercaseUrls = true);
 builder.Services.AddControllers()
+    .AddProblemDetailsConventions()
     .AddJsonOptions(o => o.JsonSerializerOptions.DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull);
 builder.Services.AddEndpointsApiExplorer();
 builder.Services.AddSwaggerGen();
@@ -19,6 +23,7 @@
 
 app.UseApplication();
 app.UseExceptionHandler(app.Environment.IsDevelopment() ? "/error-local-development" : "/error");
+app.UseProblemDetails();
 app.UseSwagger();
 app.MapControllers();
 
diff --git a/services/Directory/FilterLists.Directory.Api/SwaggerExtensions.cs b/services/Directory/FilterLists.Directory.Api/SwaggerConfigurationExtensions.cs
similarity index 96%
rename from services/Directory/FilterLists.Directory.Api/SwaggerExtensions.cs
rename to services/Directory/FilterLists.Directory.Api/SwaggerConfigurationExtensions.cs
index ba68d1de4..6829174f8 100644
--- a/services/Directory/FilterLists.Directory.Api/SwaggerExtensions.cs
+++ b/services/Directory/FilterLists.Directory.Api/SwaggerConfigurationExtensions.cs
@@ -3,7 +3,7 @@
 
 namespace FilterLists.Directory.Api;
 
-internal static class SwaggerExtensions
+internal static class SwaggerConfigurationExtensions
 {
     public static void AddSwaggerGen(this IServiceCollection services)
     {
diff --git a/services/Directory/FilterLists.Directory.Application/ConfigurationExtensions.cs b/services/Directory/FilterLists.Directory.Application/ConfigurationExtensions.cs
index 73304f209..e8e5e8b03 100644
--- a/services/Directory/FilterLists.Directory.Application/ConfigurationExtensions.cs
+++ b/services/Directory/FilterLists.Directory.Application/ConfigurationExtensions.cs
@@ -1,4 +1,5 @@
 using FilterLists.Directory.Infrastructure;
+using FluentValidation;
 using MediatR;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.Extensions.Configuration;
@@ -17,6 +18,8 @@ public static IHostBuilder ConfigureApplication(this IHostBuilder hostBuilder)
     public static void AddApplication(this IServiceCollection services, IConfiguration configuration)
     {
         services.AddMediatR(typeof(ConfigurationExtensions).Assembly);
+        services.AddTransient(typeof(IPipelineBehavior<,>), typeof(ValidatorPipelineBehavior<,>));
+        services.AddValidatorsFromAssembly(typeof(ConfigurationExtensions).Assembly, includeInternalTypes: true);
         services.AddAutoMapper(typeof(ConfigurationExtensions).Assembly);
         services.AddInfrastructure(configuration);
     }
diff --git a/services/Directory/FilterLists.Directory.Application/FilterLists.Directory.Application.csproj b/services/Directory/FilterLists.Directory.Application/FilterLists.Directory.Application.csproj
index 68617b8e7..f89c39246 100644
--- a/services/Directory/FilterLists.Directory.Application/FilterLists.Directory.Application.csproj
+++ b/services/Directory/FilterLists.Directory.Application/FilterLists.Directory.Application.csproj
@@ -18,6 +18,7 @@
 
   <ItemGroup>
     <PackageReference Include="AutoMapper.Extensions.Microsoft.DependencyInjection" Version="8.1.1" />
+    <PackageReference Include="FluentValidation.DependencyInjectionExtensions" Version="10.3.4" />
     <PackageReference Include="MediatR.Extensions.Microsoft.DependencyInjection" Version="9.0.0" />
   </ItemGroup>
 
diff --git a/services/Directory/FilterLists.Directory.Application/Queries/GetListDetails.cs b/services/Directory/FilterLists.Directory.Application/Queries/GetListDetails.cs
index ad1a9aa2b..30e592eae 100644
--- a/services/Directory/FilterLists.Directory.Application/Queries/GetListDetails.cs
+++ b/services/Directory/FilterLists.Directory.Application/Queries/GetListDetails.cs
@@ -3,6 +3,7 @@
 using FilterLists.Directory.Api.Contracts.Models;
 using FilterLists.Directory.Infrastructure.Persistence.Queries.Context;
 using FilterLists.Directory.Infrastructure.Persistence.Queries.Entities;
+using FluentValidation;
 using MediatR;
 using Microsoft.EntityFrameworkCore;
 
@@ -12,6 +13,15 @@ public static class GetListDetails
 {
     public record Query(int Id) : IRequest<ListDetailsVm?>;
 
+    internal class Validator : AbstractValidator<Query>
+    {
+        public Validator()
+        {
+            RuleFor(q => q.Id)
+                .GreaterThanOrEqualTo(0);
+        }
+    }
+
     internal class Handler : IRequestHandler<Query, ListDetailsVm?>
     {
         private readonly IQueryContext _context;
diff --git a/services/Directory/FilterLists.Directory.Application/ValidatorPipelineBahavior.cs b/services/Directory/FilterLists.Directory.Application/ValidatorPipelineBahavior.cs
new file mode 100644
index 000000000..3c3e0c4e9
--- /dev/null
+++ b/services/Directory/FilterLists.Directory.Application/ValidatorPipelineBahavior.cs
@@ -0,0 +1,27 @@
+using FluentValidation;
+using MediatR;
+
+namespace FilterLists.Directory.Application;
+
+internal class ValidatorPipelineBehavior<TRequest, TResponse> : IPipelineBehavior<TRequest, TResponse>
+    where TRequest : notnull
+{
+    private readonly IEnumerable<IValidator<TRequest>> _validators;
+
+    public ValidatorPipelineBehavior(IEnumerable<IValidator<TRequest>> validators)
+    {
+        _validators = validators;
+    }
+
+    public Task<TResponse> Handle(TRequest request,
+        CancellationToken cancellationToken,
+        RequestHandlerDelegate<TResponse> next)
+    {
+        foreach (var validator in _validators)
+        {
+            validator.ValidateAndThrow(request);
+        }
+
+        return next();
+    }
+}