# @cratestack/validator-yup

An [`RpcLink`](https://github.com/cratestack/cratestack/tree/main/packages/cratestack-ts-types)
([issue #182](https://github.com/cratestack/cratestack/issues/182)) for CrateStack's generated
TypeScript RPC client (`transport rpc` schemas) that validates `request.input` against a per-op
[yup](https://github.com/jquense/yup) schema before the call reaches the network — client-side
validation with the exact same schema shape your server-side procedure/model input already has,
instead of hoping the generated types alone catch a bad call at compile time.

## Usage

```ts
import { createYupValidatorLink } from "@cratestack/validator-yup";
import { CratestackRpcRuntime } from "./generated/runtime"; // your project's generated client
import * as yup from "yup";

const runtime = new CratestackRpcRuntime("https://api.example.com", {
  links: [
    createYupValidatorLink({
      "model.Order.create": yup.object({ total: yup.number().positive().required() }),
    }),
  ],
});
```

Ops with no configured schema pass through unvalidated — this is opt-in per op, not a blanket
gate. On success, the schema's *cast* output (defaults, type coercion) becomes the actual request
`input`, not just a type-level assertion. On failure, the chain short-circuits — the real network
call never happens — and the call rejects the same way a server-side validation failure would,
with an `RpcErrorBody` carrying `code: "invalid_argument"`.