@kingworldjs/schema

Plugin for kingworld for declaratively validation of incoming request.

Installation

bun add @kingworldjs/schema

Schema Validation

Use @kingworldjs/schema handle typed-strict validation of incoming request.

Schema validation is capable of validation of:

• body
• header
• query
• params

And optional config:

• customError (type: SchemaType, error: Error | TypeError) => any
  • Return custom error message response

Schema plugin use fastest-validator for schema validation and declaration which has full TypeScript supports and auto-complete.

Example

import KingWorld from 'kingworld'
import schema from '@kingworldjs/schema'

new KingWorld()
    .get<{
        params: {
            id: number
        }
    }>('/id/:id', ({ request: { params: { id } } }) => id, {
        transform: (request, store) {
            request.params.id = +request.params.id
        },
        preHandler: schema({
            params: {
                id: {
                    type: "number",
                    min: 1,
                    max: 100
                }
            }
        })
    })
    .listen(3000)

// [GET] /id/2 => 2
// [GET] /id/500 => Invalid params
// [GET] /id/-3 => Invalid params

To use validation on group scope, simply attach schema to preHandler:

import KingWorld from 'kingworld'
import schema from '@kingworldjs/schema'

new KingWorld()
    .group('/group', (app) => app
        .preHandler(schema({
            params: {
                id: {
                    type: "number",
                    min: 1,
                    max: 100
                }
            }
        }))
        .get<{
            params: {
                id: number
            }
        }>('/user/:id', ({ request: { params: { id } } }) => id, {
            transform: (request, store) {
                request.params.id = +request.params.id
            }
        })
        .get<{
            params: {
                id: number
            }
        }>('/post/:id', ({ request: { params: { id } } }) => id, {
            transform: (request, store) {
                request.params.id = +request.params.id
            }
        })
    )
    .listen(3000)

// [GET] /user/2 => 2
// [GET] /user/500 => Invalid params
// [GET] /post/-3 => Invalid params

Gotcha

Schema validation will be handle in order of preHandler. To make sure everything is expected, please place schema plugin before any other preHandler that might depends on schema plugin.