Fluent Schema Validator

Small validator for Fluent JSON Schema.

Don't let yourself handle validation, let the automation handle it.

Why

Fastify use Fluent JSON Schema for verifying schema of incoming request. Although, Fastify support basic validation by default, it's not enough for real world application.

For instance, having unintentionally field in the value but the schema bypass it, or having string format of email but also bypass by fastify default validator.

In fact, Fastify docs recommended that you use custom validator instead. This library help just that

Feature

• Type strict to the schema
  • No unintentional field is bypassed
• Support most of the API
  • Whether it's pattern for RegEx, string format, required field or an advances anyOf, allOf, not is supported.
• Handle all type
  • Even if it's a simple string, complex array or full-fledge recursive object, it's all support.
• It just work.
  • Edgecase like unicode email format is handled, recursive object is handled, etc.
  • No headache of setting up compiler, Fluent Schema Validator provide just a simple function which works out of the box
  • Full compatability with Fluent Schema, Fast JSON Stringify, Fastify Schema or plain object
  • As long as your schema is formatted to plain Fast JSON Stringify schema, it will work
• Small and fast
  • No dependencies required, small bundle-size considering full-fledge feature.
• CJS, ESM, MJS, TypeScript
  • Yes, it's all support, TypeScript first bundled by SWC.

Getting Start

Install the package.

npm install fluent-schema-validator fluent-json-schema

# or yarn
yarn add fluent-schema-validator fluent-json-schema

# or pnpm
pnpm add fluent-schema-validator fluent-json-schema

Then write a sample validation.

// Assumming you're using TypeScript or mjs
import S from 'fluent-json-schema'
import validate from 'fluent-schema-validator'

const schema = S.object()
    .prop('username', S.string().required())
    .prop('password', S.string().required())

const value = {
    username: "saltyaom",
    password: "12345678"
}

validate(value, schema) // true

Unintentional field

Field which is not define in schema will not be tolerate

import S from 'fluent-json-schema'
import validate from 'fluent-schema-validator'

const schema = S.object()
    .prop('username', S.string().required())
    .prop('password', S.string().required())

const value = {
    username: "saltyaom",
    password: "12345678",
    "not-in-schema": true
}

validate(value, schema) // false

Optional field

Field which is not mark required, will be fine if not presented

import S from 'fluent-json-schema'
import validate from 'fluent-schema-validator'

const schema = S.object()
    .prop('username', S.string().required())
    .prop('password', S.string())

const value = {
    username: "saltyaom",
}

validate(value, schema) // true

It would work the way you expected, see more in test cases or _specs_ folder.