This package has been deprecated

Author message:

JSNVL has been superceded by Prudence.

jsnvl

The simple Javascript Object Validator.

Notes

JSNVL is an incredibly simple Javascript Object Validator, and is designed for simple schema validation. There are other libraries available if you require more complicated validation, but this should be enough for most use cases.

Usage

• Install from NPM, npm install jsnvl

import JSNVL from "jsnvl";

---

JSNVL(object, schema, options)

• object (Object):
  • The JS object you wish to validate.
• schema (Object):
  • The schema you wish to validate the object against.
• options (Object, optional):
  • ignoreExcessKeys (Boolean, Default false): Ignores any keys present on the object that are NOT present on the schema.
  • ignoreThrownErrors (Boolean, Default false): Ignores any errors thrown by JSNVL. JSNVL throws errors on implementation issues, such as passing an invalid schema. This will convert those errors to a false return.
  • silenceLogs (Boolean, Default false): If true, JSNVL will not log any information about the validation process (such as when errors occur).

Schema Structure

Simple type checks:

let schema = {
  name: "string",
  age: "number",
  sayName: "function",
}

let object = {
  name: "Bob",
  age: 15,
  sayName: () => {}
}

JSNVL(object, schema) // true

In short, If a value in a schema is a string, JSNVL will check that the typeof comparison counterpart is equal to that string. An exception is that the string "object" checks taht the typeof is an object AND the value is not null.

Nullable type checks:

let schema = {
  name: "?string",
}

let object = {
  name: null,
}

JSNVL(object, schema) // true

Prefixing a type with ? will allow that field to be nullable.

Inside Array

let schema = {
   fruit: ["Banana","Plum"]
}

let object = {
  fruit: "Plum"
}

JSNVL(object, schema) // true

If a value inside a schema is an array, JSNVL will check if the value in the object is inside that array.

Custom

let schema = {
  oddNumber: (self) => self % 2 === 1
}

let object = {
  oddNumber: 15
}

JSNVL(object, schema) // true

If a value inside a schema is a function, JSNVL will evaluate that function, passing the value of the object as the first parameter. I encourage using self for this name, and using currying to evaluate more complex functions.

A second parameter, parent is also available, and will pass the object self is enclosed in. This can be used for conditional evaluation, such as:

let schema = {
  start: "number",
  end: (self, parent) => self > parent.start
}

let object = {
  start: 10,
  end: 15
}

JSNVL(object, schema) // true

object.end = 9;

JSNVL(object, schema) // false