Usage

NOTE: This library is intended to be used for config files, but if you really want to, you can use it like a 'runtime interface'.

Example

// dummy.ts

// import validateRc
import validateRc, { Optional, Choice } from 'validate-rc'

// the rules that the rc should follow
// rule to validate a custom package.json
const rules = {
    name: String,
    version: String,
    description: Optional(Object),
    scripts: Optional(Object),
    keywords: Array,
    dependencies: Optional(Object),
    devDependencies: Optional(Object),
    author: String,
    license: String,
    bin: Optional(Object),
    repository: Optional({
        type: String,
        url: String
    })
}

validateRc(rules, require('./package.js'))

validateRc(rules: object, rc: object): boolean | never

Takes two objects, rules and rc. rules is the object that holds the rules, rc is the object that needs to be validated.

Syntax

The rules' syntax is made of constructors and branches.

Example:

const rules = {
    // only matches numbers
    num: Number,
    // only matches strings
    str: String,
    // only matches booleans
    bool: Boolean
    // this is valid for all primitives, promises, buffers etc cannot be used
    branch: {
        // other constructors
    }
}

Optional

Optional is a function that accepts a constructor or branch. If in the config file the key associated with Optional isn't present, it does not throw. But, if that key is present and it violates the rule that is specified in Optional, throws.

Example

import validateRc, { Optional } from 'validate-rc'

const rules = { 
    age: Optional(Number),
    otherInfo: Optional({
        hobbies: Array,
        height: Number,
        name: String
    })
}

validateRc(rules, {})  // does not throw, because `age` and `otherInfo` are optional
validateRc(rules, { age: 24 }) // does not throw, because `otherInfo` is optional
validateRc(rules, {  // does not throw, because `otherInfo`'s rules are not violated
    otherInfo: {
        hobbies: [ 'Programming' ],
        height: 179,
        name: 'Michael'
    }
})
validateRc(rules, {  // throws, because `age` is a string
    age: 'string'
})
validateRc(rules, {  // throws, because `otherInfo`'s rules are violated
    otherInfo: {}
})
validateRc(rules, {  // throws, because otherInfo is a boolean and not an object
    otherInfo: false
})

Choice

Choice is a function that takes multiple arguments as choices, throws when the value in the config isn't present in Choice.

Example

import validateRc, { Optional, Choice } from 'validate-rc'

const rule = { esVersion: Optional(Choice('es5', 'es6', 'es2015', 'esnext')) }

validateRc(rule, {}) // does not throw, because its optional
validateRc(rule, { esVersion: 'es6' }) // does not throw, because 'es6' is in `Choice`
validateRc(rule, { esVersion: 'es2017' }) // throws, because 'es2017' isn't in `Choice`