DataSchemaclass

new DataSchema<T>({ one = "item", title = "Item", props, value: partialValue, ...options }: DataSchemaOptions<T>)

Param	Type
`options`	`DataSchemaOptions<T>`	Options for DataSchema. required
`.props`	`Schemas<T>`	A named schema for each property the data object must have. required readonly
`.value`	`Partial<T>`	Partial default value merged over the per-prop defaults. readonly

Return
`DataSchema<T>`	Schema that validates a data object against a fixed set of named property schemas.

Property	Type
`.props`	`Schemas<T>`	A set of named schemas in { name: schema } format. required readonly

Schema that validates a data object against a fixed set of named property schemas.

Each property is validated by its own schema in props.
Excess keys are stripped and undefined outputs removed (via validateData()).

Validates a plain object whose properties each have their own schema. The term Data in Shelving refers to a plain object with known named properties; a DataSchema is the validator for one.

When several properties fail, the errors are joined by \n with each field name prepended — e.g. "name: Required\nprice: Minimum 0". This file also exports the DATA, ITEM, and PARTIAL sugar factories that build DataSchema instances.

Usage

`DATA` — validate an object

import { DATA, BOOLEAN, StringSchema, NumberSchema } from "shelving/schema";

const PRODUCT = DATA({
  name: new StringSchema({ title: "Name", min: 1, max: 100 }),
  price: new NumberSchema({ title: "Price", min: 0 }),
  available: BOOLEAN,
});

PRODUCT.validate({ name: "Widget", price: 9.99, available: true });
// { name: "Widget", price: 9.99, available: true }

PRODUCT.validate({ name: "", price: -1, available: true });
// throws "name: Required\nprice: Minimum 0"

Use .pick() and .omit() to derive subset schemas without redefining props:

const PatchProduct = PRODUCT.omit("available");
const NameOnly = PRODUCT.pick("name");

`ITEM` — add a typed `id` field

ITEM wraps a DataSchema to add a typed id field, matching the Item type in shelving/util/item.

import { ITEM, STRING, INTEGER, NUMBER } from "shelving/schema";

const PRODUCT_ITEM = ITEM(INTEGER, {
  name: STRING,
  price: NUMBER,
}); // Validates: { id: number, name: string, price: number }

`PARTIAL` — make every field optional

PARTIAL wraps a DataSchema so every field becomes optional — useful for PATCH-style update payloads.

import { PARTIAL } from "shelving/schema";

const PARTIAL_PRODUCT = PARTIAL(PRODUCT);
PARTIAL_PRODUCT.validate({ price: 4.99 }); // { price: 4.99 }

Examples

const schema = new DataSchema({ props: { name: STRING, age: NUMBER } });
 schema.validate({ name: "Dave", age: 40 }); // { name: "Dave", age: 40 }

Methods

DataSchema.pick()method

Make a new DataSchema that only uses a defined subset of the current props.

pick(...keys: K[]): DataSchema<Pick<T, K>>

DataSchema.omit()method

Make a new DataSchema that omits one or more of the current props.

omit(...keys: K[]): DataSchema<Omit<T, K>>