Data Fixer

A tool for check and fix data with json schema, inspired by angular reactive form.

Installation

npm:

$ npm install data-fixer

yarn:

$ yarn add data-fixer

Type Definition

This project develop with TypeScript, type is build-in with publish.

Usage

There are three "Controllers" which vctrl for primivite value, actrl for array, dctrl for Dictionary, rctrl for Record, and tctrl for tuple.

Simply provide a json schema and fallback value/function to vctrl, compose one or many vctrl in other *ctrl for structural data.

vctrl demo

import Ajv from 'ajv';
import * as yup from 'yup';
import { ajvAdt, vctrl } from 'data-fixer';

// for Ajv
const isGt0 = vctrl(ajvAdt(new Ajv().compile({ type: 'number', exclusiveMinimum: 0 })), 1);
// since Ajv ValidateFunction already fit the signature of Vtor, if dev in JS, below is OK too.
// but not OK for TS, due Data Fixer only handle for sync validation.
const isGt0 = vctrl(new Ajv().compile({ type: 'number', exclusiveMinimum: 0 }), 1);

// for yup
const isGt0 = vctrl(yupAdt(yup.number().moreThan(0)), 1);

const holder1 = isGt0(0);
holder1.valid; // false
holder1.invalid; // true
holder1.value(); // 1

const holder2 = isGt0(7);
holder2.valid; // true
holder2.invalid; // false
holder2.value(); // 7

// type coercion case
const isGt0 = vctrl(ajvAdt({ type: 'number', exclusiveMinimum: 0 }, { coerceTypes: true }), 1);

const holder1 = isGt0('7');
holder1.valid; // true
holder1.invalid; // false
holder1.value(); // '7', ajv only coerce object property

// fallback function
const fallback = (data: any) => Number.isNaN(+data) ? +data : 1;
const isNumber = vctrl(ajvAdt({ type: 'number' }), fallback);

const holder = isNumber('foo');
holder.valid; // false
holder.invalid; // true
holder.value(); // 1

actrl demo

import { actrl, vctrl, ajvAdt } from 'data-fixer';

const isNumber = vctrl(ajvAdt({ type: 'number' }), 1);
const isAllNumber = actrl(isNumber);

const holder = isAllNumber([1, 2, 3, '4']);
holder.valid; // false
holder.invalid; // true
holder.value(); // [1, 2, 3, 1];

rctrl demo

import { rctrl, vctrl, ajvAdt } from 'data-fixer';

const isNumber = vctrl(ajvAdt({ type: 'number' }), 1);
const isAllNumber = rctrl(isNumber);

// rctrl can handle for object that care only for its value type
const holder = isAllNumber({ a: 1, b: 2, c: 3, d: '4' });
holder.valid; // false
holder.invalid; // true
holder.value(); // { a: 1, b: 2, c: 3, d: 1 }

dctrl demo

import { dctrl, vctrl, ajvAdt } from 'data-fixer';

const isConfig = dctrl({
  version: vctrl(ajvAdt({ type: 'number', const: 2 }), 2),
  menus: dctrl({
    enabled: vctrl({ type: 'boolean' }, false),
    clipboard: vctrl({ type: 'boolean' }, true),
  }),
});

const holder = isConfig({});
holder.valid; // false
holder.invalid; // true
holder.value(); // { version: 2, menus: { enabled: false, clipboard: true } }

tctrl demo

import { tctrl, vctrl, ajvAdt } from 'data-fixer';

const isNumber = vctrl(ajvAdt({ type: 'number' }), 1);
const isString = vctrl(ajvAdt({ type: 'string' }), 'a');
const isNumberString = tctrl(isNumber, isString);

// tctrl can check tuple type array
const holder = isNumberString([1, 1]);
holder.valid; // false
holder.invalid; // true
holder.value(); // [1, 'a']

Infer type in TypeScript

Most of the time the return value of Holder.value() have the correct type, due it infer the type from the alt type.

import Ajv from 'ajv';
import { ajvAdt } from '../adapter';
import { vctrl } from '../vctrl/vctrl';
import { dctrl } from './dctrl';

const ctrl = dctrl({
  version: vctrl(ajvAdt(new Ajv().compile({ type: 'number', const: 2 })), 2),
  menus: dctrl({
    enabled: vctrl(ajvAdt(new Ajv().compile({ type: 'boolean' })), false),
    clipboard: vctrl(ajvAdt(new Ajv().compile({ type: 'boolean' })), true),
  }),
});

const holder = ctrl({ version: 2, menus: { enabled: true, clipboard: true } });

// typeof holder.value()
{
  version: number;
  menus: {
    enabled: boolean;
    clipboard: boolean;
  };
}

// The infer result is good, but the version is actually a constant 2 rather than just number.
// There are two ways you can fix this.

// either
vctrl<2>(ajvAdt(new Ajv().compile({ type: 'number', const: 2 })), 2);
// or
vctrl(ajvAdt(new Ajv().compile({ type: 'number', const: 2 })), 2 as 2);

Caveats

• Data Fixer is currently only handle for sync validation.

More

Data Fixer let developer choose schema validator by using adapter, currently support Ajv and yup. For how to define the schema, please check the below informations:

• For Ajv, please check here .
• For yup, please check here .