init

src/Common/Mccn.Common.Application/Behaviors/ValidationBehavior.cs

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+using FluentValidation;
+using FluentValidation.Results;
+using Mccn.Common.Application.Exceptions;
+using Mccn.Common.Domain.Abstractions;
+using MediatR;
+using ValidationException = Mccn.Common.Application.Exceptions.ValidationException;
+
+namespace Mccn.Common.Application.Behaviors;
+
+public sealed class ValidationBehavior<TRequest, TResponse> : IPipelineBehavior<TRequest, TResponse>
+    where TRequest : IBaseRequest
+    where TResponse : Result
+{
+    private readonly IEnumerable<IValidator<TRequest>> _validators;
+
+    public ValidationBehavior(IEnumerable<IValidator<TRequest>> validators)
+    {
+        _validators = validators;
+    }
+
+    public async Task<TResponse> Handle(
+        TRequest request,
+        RequestHandlerDelegate<TResponse> next,
+        CancellationToken cancellationToken)
+    {
+        ValidationContext<TRequest> context = new(request);
+
+        ValidationResult[] validationFailures = await Task.WhenAll(
+            _validators.Select(v => v.ValidateAsync(context, cancellationToken)));
+
+        List<ValidationError> errors = validationFailures
+            .Where(r => !r.IsValid)
+            .SelectMany(r => r.Errors)
+            .Select(f => new ValidationError(f.PropertyName, f.ErrorMessage))
+            .ToList();
+
+        if (errors.Count != 0) throw new ValidationException(errors);
+
+        return await next();
+    }
+}