can-validate-interface/can-validate-interface.md

Utility to validate property existence. Test for missing properties before they cause errors later.

@module {{}} can-validate-interface
@parent can-data-validation
@collection can-infrastructure
@package ./package.json

@description `can-validate-interface` provides simple property existence validation. Use to prevent errors resulting
from missing properties on input objects.


@signature `makeInterfaceValidator(propertyArrays)`

Get a function that validates a given object for the provided properties:

```js
import makeInterfaceValidator from "can-validate-interface";
const dataMethods = [ "create", "read", "update", "delete" ];
const daoValidator = makeInterfaceValidator( [ dataMethods, "id" ] );

const dao = {
	create: function() {},
	read: function() {},
	update: function() {},
	delete: function() {}
};

let errors = daoValidator( dao );

// errors == {message:"missing expected properties", related: ["id"]}

dao.id = 10;

errors = daoValidator( dao );

// errors == undefined
```

@param {Array.<String, Array.<String>>} propertyArrays Property names and arrays of property names to validate existence of

@return {function({*}): {{message:String, related:Array.<String>}}} Function that validates an object for properties in propertyArrays and returns an error record or undefined if no properties are missing.