FluentAnnotationsValidator 1.2.1

FluentAnnotationsValidator

A fluent, type-safe validation engine for .NET that transforms [ValidationAttribute] annotations into runtime validation logic. Supports conditional rules, culture-scoped messages, and discoverable configuration via DSL.

Features

• Automatic validation from [Required], [Range], [StringLength], etc.
• Runtime error message resolution with localization fallback
• .resx-based resource binding with auto-assigned CultureInfo
• DSL configuration: target types, cultures, resource mapping, conventions

Quick Setup

Certainly — here’s a refined version that’s clearer, more discoverable, and contributor-friendly. It emphasizes the fluent entry point, scoped configuration, and conditional override with dynamic localization fallback:

Fluent Validation Configuration

Start with automatic rule generation via [ValidationAttribute], then layer culture and localization resources:

using FluentAnnotationsValidator.Extensions;
using System.Globalization;

services.UseFluentAnnotations()
    .For<LoginDto>()
        .WithCulture(CultureInfo.GetCultureInfo("fr-FR"))
        .WithValidationResource<ValidationMessages>() // Scoped .resx lookup
    .Build();

Or inject conditional validation logic with localized error fallback:

services.UseFluentAnnotations()
    .For<LoginDto>()
        .WithCulture(CultureInfo.GetCultureInfo("fr-FR"))
        .WithValidationResource<ValidationMessages>()
        .When(x => x.Password, dto => string.IsNullOrEmpty(dto.Password))
            .Localized("Password_Required")            // Looks up ValidationMessages.Password_Required
            .UseFallbackMessage("Mot de passe requis.") // Fallback if resource key is missing
    .Build();

Highlights

• WithCulture(...) binds CultureInfo globally across rules for this type.
• WithValidationResource<T>() uses .resx-backed messages with safe fallback.
• When(...) applies targeted conditions with fluent chaining for per-property logic.
• Localized(...) uses string keys like "Email_Required", typically mapped to ValidationMessages resource entries.

Documentation

See configuration guide for advanced usage.

Contribute

Open to feedback, extensions, and collaboration - shape validation ergonomics for developers worldwide.