Json Joi

json-Joi-converter

json-Joi-converter is a robust TypeScript module built on top of the popular Joi library. This package seamlessly converts Joi schemas to JSON and back, enabling effortless creation of Joi schemas to and from JSON.

Why Choose json-Joi-converter?

Do you need to share the same Joi schema between your backend and frontend? This module makes it simple!

• Generate a JSON representation of your Joi schema on the backend.
• Use that JSON to recreate the Joi schema on the frontend, ensuring consistent validation across your application.

About Joi

Joi is known as "the most powerful schema description language and data validator for JavaScript." json-Joi-converter extends its capabilities to make schema sharing and reuse even more efficient.

See Joi API for documentation and api.

Try demo

https://siavashg.com/json-joi-demo/

Installation

npm install json-joi-converter

Usage

import Joi, {fromJson, toJson, Schema} from 'json-joi-converter';

const json: Schema = {
  type: "object",
  properties: {
    a: {
      type: "number",
      min: 100,
      max: 1000,
      required: true
    }
  }
};

// fromJson(json) is equal to following

const joi = Joi.object({
  a: Joi.number().min(100).max(1000).required()
});

// VALID
assert.deepEqual(toJson(joi), toJson(fromJson(json)));

Joi Reference & Functions

{
  a: {
    type: "number"
  },
  b: {
    type: "number",
    min: {
      $ref: "a",
      adjust: "value => value + 1"
    }
  }
}

// where adjust is a stringed function

// is equal to
Joi.object({
  a: Joi.number(),
  b: Joi.number.min(Joi.ref("a", {
    adjust: value => value + 1
  }))
})

Joi RegExp

let json: ObjectSchema = {
  type: "object",
  properties: {
    a: {
      type: "string",
      pattern: "/a/"
    },
    b: {
      type: "string",
      regex: {$regex: "/a/", flags: "i"}
    },
    c: {
      type: "string",
      regex: {pattern: {$regex: "/a/"}}
    }
  }
};

const converted = (toJson(fromJson(json)) as any);

assert.equal(converted.properties?.a?.pattern?.regex?.$regex, '\\/a\\/');
assert.equal(converted.properties?.b?.pattern?.regex?.$regex, '\\/a\\/');
assert.equal(converted.properties?.b?.pattern?.regex?.flags, 'i');
assert.equal(converted.properties?.c?.pattern?.regex?.$regex, '\\/a\\/');

Joi Replace

{
  type: "string",
  replace: {find: {$regex: "a", flags: "gi"}, replace: "b"}
}

// is equal to
Joi.string().replace(/a/gi, "b")

{
  type: "string",
  replace: [
    {find: {$regex: "a", flags: "gi"}, replace: "b"},
    {find: "a", replace: "b"}
  ]
}

// is equal to
Joi.string().replace(/a/gi, "b").replace("a", "b")