FluentValidation is out and available to download from Nuget. This is a major release with several breaking change, so please make sure you read the upgrade notes before upgrading.

Validating properties by path

You can now validate specific properties using a full path, eg:

validator.Validate(customer, "Address.Line1", "Address.Line2");

Validating a specific ruleset with SetValidator

Previously, if you defined a child validator with SetValidator, then whichever ruleset you invoked on the parent validator will cascade to the child validator. Now you can explicitly define which ruleset will run on the child:

RuleFor(x => x.Address).SetValidator(new AddressValidator(), "myRuleset");

AttrbiutedValidatorFactory has been moved to a separate package

The ValidatorAttribute and the AttributedValidatorFactory were typically used in MVC/WebApi projects to wire models to their validators. This is no longer recommended when usign AspNetCore as the built-in Service Provider is a better alternative. These classes can still be used by explicitly installing the FluentValidation.ValidatorAttribute package. Note this package is installed by default if you are using the legacy MVC5/WebApi integration rather than AspNetCore.

SetCollectionValidator is deprecated

RuleForEach provides a more flexible syntax for the same result.

Async changes

Internally, the asynchronous validation API has been cleaned up thanks to await\async. From a consumer’s point of view, the asynchronous methods should all continue to work as before with the exception of some methods that previously didn’t take a CancellationToken that now do.

The full changelog is available here