Hi everyone.

Most Symfony API validation patterns feel over-engineered to me. Too many layers, too much boilerplate, and endless desync between validation logic and OpenAPI docs. I got tired of SOLID-pattern hell and built a pragmatic solution for my own projects.

The approach: I use JSON Schema as the Single Source of Truth. It handles request validation, maps data to DTOs, and automatically keeps Nelmio/Swagger documentation in sync.

What it looks like in a controller:

#[Route('/api/products/search', methods: ['GET'])]
public function search(#[MapRequest('product-search.json')] ProductSearchDto $dto): JsonResponse
{
    // Documentation and validation are already handled.
    // $dto is populated and valid.
}

Why it’s better than standard "best practices":

• No more "lying" documentation.
• No more DTO/Assertion spaghetti.
• JSON Schema is flexible enough to handle complex, dynamic requirements that traditional validation fails at.

If you’re tired of infinite abstractions and just want to ship working code, check it out:

• Repo: github.com/outcomer/symfony-json-schema-validation
• Docs: outcomer.github.io/symfony-json-schema-validation

Cheers ))