Complex model validation for server and client made easy.

Write complex model validation rules in C# once. Dryv will generate JavaScript for client-side validation.

Features

1. Automatically translates validation expressions from C# to JavaScript.
2. Supports asynchronous validation expressions.
3. Supports dependency-injection into validation expressions (e.g. for ASP.NET options).
4. Automatically generates ASP.NET controllers at runtime for custom async validation rules.
5. Integrates into the ASP.NET model validation.

Installation

.NET Standard 1.2

Install-Package Dryv

ASP.NET Core 3.1

Install-Package Dryv.AspNetCore 

Usage

.NET Standard 1.2

using Dryv.Rules;

public class Address
{
    private static DryvRules<Address> ValidationRules = DryvRules.For<Address>()
        .Rule(a => a.City, a => string.IsNullOrWhiteSpace(a.City) ? "Please enter a city." : null)
        .Rule(a => a.ZipCode, a => string.IsNullOrWhiteSpace(a.ZipCode) ? "Please enter a ZIP code." : null)
        .Rule(a => a.ZipCode, a => a.ZipCode.Trim().Length < 5 ? "ZIP code must have at least 5 characters." : null)
        .Rule<AsyncValidator, SampleOptions>(a => a.ZipCode, (a, v, o) => v.ValidateZipCode(a.ZipCode, a.City, o.Strict));

    [DryvRules]
    public string City { get; set; }

    [DryvRules]
    public string ZipCode { get; set; }
}

public class HomeModel
{
    public Address BillingAddress { get; set; }
    public Address ShippingAddress { get; set; }
    public Person Person { get; set; }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Dryv.Compilation;
using Dryv.Configuration;
using Dryv.RuleDetection;
using Dryv.Validation;
using Dryv.SampleConsole.Models;

internal class Program
{
    private static async Task Main()
    {
        var model = new HomeModel
        {
            // ..
        };

        var validator = new DryvValidator();
        var errors = await validator.Validate(model, Activator.CreateInstance);

        foreach (var error in from e in errors
                              from m in e.Message
                              select m.Type + " " + e.Path + ": " + m.Text)
        {
            Console.WriteLine(error);
        }
    }
}

ASP.NET Core 3.1

using Dryv.AspNetCore;
using Dryv.AspNetCore.DynamicControllers;
using Dryv.Configuration;
using Dryv.Validation;
using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.DependencyInjection;

public class Startup
{
    public void Configure(IApplicationBuilder app)
    {
        // ..

        app.UseDryv();

        // ..
    }

    public void ConfigureServices(IServiceCollection services)
    {
        // ..

        services
            .AddMvc()
            .AddDryv(options => options.UseClientFunctionWriter<DryvAsyncClientValidationFunctionWriter>())
            .AddDryvDynamicControllers(options => options.HttpMethod = DryvDynamicControllerMethods.Get)
            .AddDryvPreloading();

        // ..
    }
}

@model HomeModel

<!.. some HTML  ..>

<script>
    window.dryv = window.dryv || {};
    window.dryv.validators = @Html.Raw(string.Join(",\n", from val in Html.GetDryvClientValidationFunctions()
                                                          select $@"""{val.Key}"": {val.Value}"));
</script>

window.dryv.validators = {
    validators: "billingAddress.zipCode": function(m, context) {
        return [
            function(a) {
                return (!/\S/.test(a.billingAddress.zipCode || "") ? "Please enter a ZIP code." : null);
            },
            function(a) {
                return ((a.billingAddress.zipCode.trim().length < 5) ? "ZIP code must have at least 5 characters." : null);
            },
            function(a, v, o) {
                return dryv.validateAsync('/validation/DryvDynamic1/ValidateZipCode', 'GET', {
                    zipCode: a.billingAddress.zipCode,
                    city: a.billingAddress.city
                });
            },
        ].reduce(function(promiseChain, currentTask) {
            return promiseChain.then(function(error) {
                return error || currentTask(m, context);
            });
        }, Promise.resolve());
    },
    // ...
};