Skip to content

sinclairzx81/typebox

Repository files navigation

TypeBox

JSON Schema Type Builder with Static Type Resolution for TypeScript



npm version Downloads GitHub CI

Install

Node

$ npm install @sinclair/typebox --save

Deno and ESM

import { Static, Type } from 'https://esm.sh/@sinclair/typebox'

Example

import { Static, Type } from '@sinclair/typebox'

const T = Type.String()     // const T = { type: 'string' }

type T = Static<typeof T>   // type T = string

Overview

TypeBox is a type builder library that creates in-memory JSON Schema objects that can be statically inferred as TypeScript types. The schemas produced by this library are designed to match the static type checking rules of the TypeScript compiler. TypeBox enables one to create a unified type that can be statically checked by TypeScript and runtime asserted using standard JSON Schema validation.

TypeBox is designed to enable JSON schema to compose with the same flexibility as TypeScript's type system. It can be used either as a simple tool to build up complex schemas or integrated into REST and RPC services to help validate data received over the wire.

License MIT

Contents

Usage

The following demonstrates TypeBox's general usage.

import { Static, Type } from '@sinclair/typebox'

//--------------------------------------------------------------------------------------------
//
// Let's say you have the following type ...
//
//--------------------------------------------------------------------------------------------

type T = {
  id: string,
  name: string,
  timestamp: number
}

//--------------------------------------------------------------------------------------------
//
// ... you can express this type in the following way.
//
//--------------------------------------------------------------------------------------------

const T = Type.Object({                              // const T = {
  id: Type.String(),                                 //   type: 'object',
  name: Type.String(),                               //   properties: { 
  timestamp: Type.Integer()                          //     id: { 
})                                                   //       type: 'string' 
                                                     //     },
                                                     //     name: { 
                                                     //       type: 'string' 
                                                     //     },
                                                     //     timestamp: { 
                                                     //       type: 'integer' 
                                                     //     }
                                                     //   }, 
                                                     //   required: [
                                                     //     'id',
                                                     //     'name',
                                                     //     'timestamp'
                                                     //   ]
                                                     // } 

//--------------------------------------------------------------------------------------------
//
// ... then infer back to the original static type this way.
//
//--------------------------------------------------------------------------------------------

type T = Static<typeof T>                            // type T = {
                                                     //   id: string,
                                                     //   name: string,
                                                     //   timestamp: number
                                                     // }

//--------------------------------------------------------------------------------------------
//
// ... then use the type both as JSON schema and as a TypeScript type.
//
//--------------------------------------------------------------------------------------------

function receive(value: T) {                         // ... as a Type

  if(JSON.validate(T, value)) {                      // ... as a Schema
  
    // ok...
  }
}

Types

TypeBox provides a set of functions that allow you to compose JSON Schema similar to how you would compose static types with TypeScript. Each function creates a JSON schema fragment which can compose into more complex types. The schemas produced by TypeBox can be passed directly to any JSON Schema compliant validator, or used to reflect runtime metadata for a type.

Standard

The following table lists the standard TypeBox types.

┌────────────────────────────────┬─────────────────────────────┬────────────────────────────────┐
 TypeBox                         TypeScript                   JSON Schema                    
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Any()            type T = any                 const T = { }                  
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Unknown()        type T = unknown             const T = { }                  
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.String()         type T = string              const T = {                    
                                                                type: 'string'               
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Number()         type T = number              const T = {                    
                                                                type: 'number'               
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Integer()        type T = number              const T = {                    
                                                                type: 'integer'              
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Boolean()        type T = boolean             const T = {                    
                                                                type: 'boolean'              
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Null()           type T = null                const T = {                    
                                                                 type: 'null'                
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.RegEx(/foo/)     type T = string              const T = {                    
                                                                 type: 'string',             
                                                                 pattern: 'foo'              
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Literal(42)      type T = 42                  const T = {                    
                                                                 const: 42,                  
                                                                 type: 'number'              
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Array(           type T = number[]            const T = {                    
   Type.Number()                                                type: 'array',               
 )                                                              items: {                     
                                                                  type: 'number'             
                                                                }                            
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Object({type T = {                   const T = {                    
   x: Type.Number(),               x: number,                   type: 'object',              
   y: Type.Number()                y: number                    properties: { })                              }                                 x: {                      
                                                                     type: 'number'          
                                                                   },                        
                                                                   y: {                      
                                                                     type: 'number'          
                                                                   }                         
                                                                },                           
                                                                required: ['x', 'y']         
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Tuple([          type T = [number, number]    const T = {                    
   Type.Number(),                                               type: 'array',               
   Type.Number()                                                items: [{                    
 ])                                                                type: 'number'            
                                                                 }, {                        
                                                                   type: 'number'            
                                                                 }],                         
                                                                 additionalItems: false,     
                                                                 minItems: 2,                
                                                                 maxItems: 2                 
                                                              }                              
                                                                                             
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 enum Foo {                      enum Foo {                   const T = {                    
   A,                              A,                           anyOf: [{                    
   B                               B                              type: 'number', }                               }                                const: 0                   
                                                                }, { const T = Type.Enum(Foo)        type T = Foo                     type: 'number',            
                                                                  const: 1                   
                                                                }]                           
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.KeyOf(           type T = keyof {             const T = {                    
   Type.Object({                   x: number,                   anyOf: [{                    
     x: Type.Number(),             y: number                      type: 'string',            
     y: Type.Number()            }                                const: 'x'                 
   })                                                           }, {                         
 )                                                                type: 'string',            
                                                                  const: 'y'                 
                                                                }]                           
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Union([          type T = string | number     const T = {                    
   Type.String(),                                               anyOf: [{                    
   Type.Number()                                                   type: 'string'            
 ])                                                             }, {                         
                                                                   type: 'number'            
                                                                }]                           
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Intersect([      type T = {                   const T = {                    
   Type.Object({                   x: number                    type: 'object',              
     x: Type.Number()            } & {                          properties: {   }),                             y: number                      x: {                       
   Type.Object({}                                  type: 'number'           
     y: Type.Number()                                             },                         
   })                                                             y: {                       
 ])                                                                 type: 'number'           
                                                                  }                          
                                                                },                           
                                                                required: ['x', 'y']         
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Never()          type T = never               const T = {                    
                                                                allOf: [{                    
                                                                  type: 'number'             
                                                                  const: 0                   
                                                                }, {                         
                                                                  type: 'number'             
                                                                  const: 1                   
                                                                }]                           
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Record(          type T = Record<             const T = {                    
   Type.String(),                  string,                      type: 'object',              
   Type.Number()                   number,                      patternProperties: {         
 )                               >                                '^.*$': {                  
                                                                    type: 'number'           
                                                                  }                          
                                                                }                            
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Partial(         type T = Partial<{           const T = {                    
   Type.Object({                   x: number,                   type: 'object',              
     x: Type.Number(),             y: number                    properties: {                
     y: Type.Number()           | }>                               x: {                       
   })                                                               type: 'number'           
 )                                                                },                         
                                                                  y: {                       
                                                                    type: 'number'           
                                                                  }                          
                                                                }                            
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Required(        type T = Required<{          const T = {                    
   Type.Object({                   x?: number,                  type: 'object',              
     x: Type.Optional(             y?: number                   properties: {                
       Type.Number()            | }>                               x: {                       
     ),                                                             type: 'number'           
     y: Type.Optional(                                            },                         
       Type.Number()                                              y: {                       
     )                                                              type: 'number'           
   })                                                             }                          
 )                                                              },                           
                                                                required: ['x', 'y']         
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Pick(            type T = Pick<{              const T = {                    
   Type.Object({                   x: number,                   type: 'object',              
     x: Type.Number(),             y: number                    properties: {                
     y: Type.Number()           | }, 'x'>                          x: {                       
   }), ['x']                                                        type: 'number'           
 )                                                                }                          
                                                                },                           
                                                                required: ['x']              
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Omit(            type T = Omit<{              const T = {                    
   Type.Object({                   x: number,                   type: 'object',              
     x: Type.Number(),             y: number                    properties: {                
     y: Type.Number()           | }, 'x'>                          y: {                       
   }), ['x']                                                        type: 'number'           
 )                                                                }                          
                                                                },                           
                                                                required: ['y']              
                                                              }                              
                                                                                             
└────────────────────────────────┴─────────────────────────────┴────────────────────────────────┘

Modifiers

TypeBox provides modifiers that can be applied to an objects properties. This allows for optional and readonly to be applied to that property. The following table illustates how they map between TypeScript and JSON Schema.

┌────────────────────────────────┬─────────────────────────────┬────────────────────────────────┐
 TypeBox                         TypeScript                   JSON Schema                    
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Object({         type T = {                   const T = {                    
   name: Type.Optional(            name?: string                type: 'object',              
     Type.String()               }                              properties: {                
   )                                                               name: {                   
 })  	                                                              type: 'string'          
                                                                   }                         
                                                                }                            
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Object({         type T = {                   const T = {                    
   name: Type.Readonly(            readonly name: string        type: 'object',              
     Type.String()               }                              properties: {                
   )                                                              name: {                    
 })  	                                                             type: 'string'           
                                                                  }                          
                                                                },                           
                                                                required: ['name']           
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Object({         type T = {                   const T = {                    
   name: Type.ReadonlyOptional(    readonly name?: string       type: 'object',              
     Type.String()               }                              properties: {                
   )                                                              name: {                    
 })  	                                                             type: 'string'           
                                                                  }                          
                                                                }                            
                                                              }                              
                                                                                             
└────────────────────────────────┴─────────────────────────────┴────────────────────────────────┘

Options

You can pass additional JSON schema options on the last argument of any given type. The following are some examples.

// string must be an email
const T = Type.String({ format: 'email' })

// number must be a multiple of 2
const T = Type.Number({ multipleOf: 2 })

// array must have at least 5 integer values
const T = Type.Array(Type.Integer(), { minItems: 5 })

Extended

In addition to JSON schema types, TypeBox provides several extended types that allow for the composition of function and constructor types. These additional types are not valid JSON Schema and will not validate using typical JSON Schema validation. However, these types can be used to frame JSON schema and describe callable interfaces that may receive JSON validated data. These types are as follows.

┌────────────────────────────────┬─────────────────────────────┬────────────────────────────────┐
 TypeBox                         TypeScript                   Extended Schema                
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Constructor([    type T = new (               const T = {                    
   Type.String(),                 arg0: string,                 type: 'constructor'          
   Type.Number()                  arg1: number                  parameters: [{               
 ], Type.Boolean())              ) => boolean                     type: 'string'             
                                                                }, {                         
                                                                  type: 'number'             
                                                                }],                          
                                                                return: {                    
                                                                  type: 'boolean'            
                                                                }                            
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Function([       type T = (                   const T = {                    
|   Type.String(),                 arg0: string,                 type : 'function',           
   Type.Number()                  arg1: number                  parameters: [{               
 ], Type.Boolean())              ) => boolean                     type: 'string'             
                                                                }, {                         
                                                                  type: 'number'             
                                                                }],                          
                                                                return: {                    
                                                                  type: 'boolean'            
                                                                }                            
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Uint8Array()     type T = Uint8Array          const T = {                    
                                                                type: 'object',              
                                                                specialized: 'Uint8Array'    
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Promise(         type T = Promise<string>     const T = {                    
   Type.String()                                                type: 'promise',             
 )                                                              item: {                      
                                                                  type: 'string'             
                                                                }                            
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Undefined()      type T = undefined           const T = {                    
                                                                type: 'object',              
                                                                specialized: 'Undefined'     
                                                              }                              
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Type.Void()           type T = void                const T = {                    
                                                                type: 'null'                 
                                                              }                              
                                                                                             
└────────────────────────────────┴─────────────────────────────┴────────────────────────────────┘

Reference

Use Type.Ref(...) to create referenced types. The target type must specify an $id.

const T = Type.String({ $id: 'T' })                  // const T = {
                                                     //    $id: 'T',
                                                     //    type: 'string'
                                                     // }
                                             
const R = Type.Ref(T)                                // const R = {
                                                     //    $ref: 'T'
                                                     // }

Recursive

Use Type.Recursive(...) to create recursive types.

const Node = Type.Recursive(Node => Type.Object({    // const Node = {
  id: Type.String(),                                 //   $id: 'Node',
  nodes: Type.Array(Node)                            //   type: 'object',
}), { $id: 'Node' })                                 //   properties: {
                                                     //     id: {
                                                     //       type: 'string'
                                                     //     },
                                                     //     nodes: {
                                                     //       type: 'array',
                                                     //       items: {
                                                     //         $ref: 'Node'
                                                     //       }
                                                     //     }
                                                     //   },
                                                     //   required: [
                                                     //     'id',
                                                     //     'nodes'
                                                     //   ]
                                                     // }

type Node = Static<typeof Node>                      // type Node = {
                                                     //   id: string
                                                     //   nodes: Node[]
                                                     // }

function test(node: Node) {
  const id = node.nodes[0].nodes[0]                  // id is string
                 .nodes[0].nodes[0]
                 .id
}

Generic

Use functions to create generic types. The following creates a generic Nullable<T> type.

import { Type, Static, TSchema } from '@sinclair/typebox'

const Nullable = <T extends TSchema>(type: T) => Type.Union([type, Type.Null()])

const T = Nullable(Type.String())                    // const T = {
                                                     //   anyOf: [{
                                                     //     type: 'string'
                                                     //   }, {
                                                     //     type: 'null'
                                                     //   }]
                                                     // }

type T = Static<typeof T>                            // type T = string | null

const U = Nullable(Type.Number())                    // const U = {
                                                     //   anyOf: [{
                                                     //     type: 'number'
                                                     //   }, {
                                                     //     type: 'null'
                                                     //   }]
                                                     // }

type U = Static<typeof U>                            // type U = number | null

Conditional

Use the conditional module to create Conditional Types. This module implements TypeScript's structural equivalence checks to enable TypeBox types to be conditionally inferred at runtime. This module also provides the Extract and Exclude utility types which are expressed as conditional types in TypeScript.

The conditional module is provided as an optional import.

import { Conditional } from '@sinclair/typebox/conditional'

The following table shows the TypeBox mappings between TypeScript and JSON schema.

┌────────────────────────────────┬─────────────────────────────┬────────────────────────────────┐
 TypeBox                         TypeScript                   JSON Schema                    
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Conditional.Extends(  type T =                     const T = {                    
   Type.String(),                 string extends number         const: false,                
   Type.Number(),                 true : false                  type: 'boolean'              
   Type.Literal(true),                                        }                              
   Type.Literal(false)                                                                       
 )                                                                                           
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Conditional.Extract(  type T = Extract<            const T = {                    
   Type.Union([                    'a' | 'b' | 'c',             anyOf: [{                    
     Type.Literal('a'),            'a' | 'f'                      const: 'a'                 
     Type.Literal('b'),          >                                type: 'string'             
     Type.Literal('c')                                          }]                           
   ]),                                                        }                              
   Type.Union([                                                                              
     Type.Literal('a'),                                                                      
     Type.Literal('f')                                                                       
   ])                                                                                        
 )                                                                                           
                                                                                             
├────────────────────────────────┼─────────────────────────────┼────────────────────────────────┤
 const T = Conditional.Exclude(  type T = Exclude<            const T = {                    
   Type.Union([                    'a' | 'b' | 'c',             anyOf: [{                    
     Type.Literal('a'),            'a'                            const: 'b',                
     Type.Literal('b'),          >                                type: 'string'             
     Type.Literal('c')                                          }, {                         
   ]),                                                            const: 'c',                
   Type.Union([                                                   type: 'string'             
     Type.Literal('a')                                          }]                           
   ])                                                         }                              
 )                                                                                           
                                                                                             
└────────────────────────────────┴─────────────────────────────┴────────────────────────────────┘

Unsafe

Use Type.Unsafe(...) to create custom schemas with user defined inference rules.

const T = Type.Unsafe<string>({ type: 'number' })    // const T = {
                                                     //   type: 'number'
                                                     // }

type T = Static<typeof T>                            // type T = string

This function can be used to create custom schemas for validators that require specific schema representations. An example of this might be OpenAPI's nullable and enum schemas which are not provided by TypeBox. The following demonstrates using Type.Unsafe(...) to create these types.

import { Type, Static, TSchema } from '@sinclair/typebox'

//--------------------------------------------------------------------------------------------
//
// Nullable<T>
//
//--------------------------------------------------------------------------------------------

function Nullable<T extends TSchema>(schema: T) {
  return Type.Unsafe<Static<T> | null>({ ...schema, nullable: true })
}

const T = Nullable(Type.String())                    // const T = {
                                                     //   type: 'string',
                                                     //   nullable: true
                                                     // }

type T = Static<typeof T>                            // type T = string | null


//--------------------------------------------------------------------------------------------
//
// StringEnum<string[]>
//
//--------------------------------------------------------------------------------------------

function StringEnum<T extends string[]>(values: [...T]) {
  return Type.Unsafe<T[number]>({ type: 'string', enum: values })
}

const T = StringEnum(['A', 'B', 'C'])                // const T = {
                                                     //   enum: ['A', 'B', 'C']
                                                     // }

type T = Static<typeof T>                            // type T = 'A' | 'B' | 'C'

Guards

Use the guard module to test if values are TypeBox types.

import { TypeGuard } from '@sinclair/typebox/guard'

const T = Type.String()

if(TypeGuard.TString(T)) {
    
  // T is TString
}

Strict

TypeBox schemas contain the Kind and Modifier symbol properties. These properties are provided to enable runtime type reflection on schemas, as well as helping TypeBox internally compose types. These properties are not strictly valid JSON schema; so in some cases it may be desirable to omit them. TypeBox provides a Type.Strict() function that will omit these properties if necessary.

const T = Type.Object({                              // const T = {
  name: Type.Optional(Type.String())                 //   [Kind]: 'Object',
})                                                   //   type: 'object',
                                                     //   properties: {
                                                     //     name: {
                                                     //       [Kind]: 'String',
                                                     //       type: 'string',
                                                     //       [Modifier]: 'Optional'
                                                     //     }
                                                     //   }
                                                     // }

const U = Type.Strict(T)                             // const U = {
                                                     //   type: 'object', 
                                                     //   properties: { 
                                                     //     name: { 
                                                     //       type: 'string' 
                                                     //     } 
                                                     //   } 
                                                     // }

Values

TypeBox includes an optional values module that can be used to perform common operations on JavaScript values. This module enables one to create, check and cast values from types. It also provides functionality to check equality, clone and diff and patch JavaScript values. The value module is provided as an optional import.

import { Value } from '@sinclair/typebox/value'

Create

Use the Create function to create a value from a TypeBox type. TypeBox will use default values if specified.

const T = Type.Object({ x: Type.Number(), y: Type.Number({ default: 42 }) })

const A = Value.Create(T)                            // const A = { x: 0, y: 42 }

Clone

Use the Clone function to deeply clone a value

const A = Value.Clone({ x: 1, y: 2, z: 3 })          // const A = { x: 1, y: 2, z: 3 }

Check

Use the Check function to type check a value

const T = Type.Object({ x: Type.Number() })

const R = Value.Check(T, { x: 1 })                   // const R = true

Cast

Use the Cast function to cast a value into a type. The cast function will retain as much information as possible from the original value.

const T = Type.Object({ x: Type.Number(), y: Type.Number() }, { additionalProperties: false })

const X = Value.Cast(T, null)                        // const X = { x: 0, y: 0 }

const Y = Value.Cast(T, { x: 1 })                    // const Y = { x: 1, y: 0 }

const Z = Value.Cast(T, { x: 1, y: 2, z: 3 })        // const Z = { x: 1, y: 2 }

Equal

Use the Equal function to deeply check for value equality.

const R = Value.Equal(                               // const R = true
  { x: 1, y: 2, z: 3 },
  { x: 1, y: 2, z: 3 }
)

Diff

Use the Diff function to produce a sequence of edits to transform one value into another.

const E = Value.Diff<any>(                          // const E = [
  { x: 1, y: 2, z: 3 },                             //   { type: 'update', path: '/y', value: 4 },
  { y: 4, z: 5, w: 6 }                              //   { type: 'update', path: '/z', value: 5 },
)                                                   //   { type: 'insert', path: '/w', value: 6 },
                                                    //   { type: 'delete', path: '/x' }
                                                    // ]

Patch

Use the Patch function to apply edits

const A = { x: 1, y: 2 }

const B = { x: 3 }

const E = Value.Diff<any>(A, B)                      // const E = [
                                                     //   { type: 'update', path: '/x', value: 3 },
                                                     //   { type: 'delete', path: '/y' }
                                                     // ]

const C = Value.Patch<any>(A, E)                     // const C = { x: 3 }

Errors

Use the Errors function enumerate validation errors.

const T = Type.Object({ x: Type.Number(), y: Type.Number() })

const R = [...Value.Errors(T, { x: '42' })]          // const R = [{
                                                     //   schema: { type: 'number' },
                                                     //   path: '/x',
                                                     //   value: '42',
                                                     //   message: 'Expected number'
                                                     // }, {
                                                     //   schema: { type: 'number' },
                                                     //   path: '/y',
                                                     //   value: undefined,
                                                     //   message: 'Expected number'
                                                     // }]

TypeCheck

TypeBox is written to target JSON Schema Draft 6 and can be used with any Draft 6 compliant validator. TypeBox is developed and tested against Ajv and can be used in any application already making use of this validator. Additionally, TypeBox also provides an optional type compiler that can be used to attain improved compilation and validation performance for certain application types.

Ajv

The following example shows setting up Ajv to work with TypeBox.

$ npm install ajv ajv-formats --save
import { Type }   from '@sinclair/typebox'
import addFormats from 'ajv-formats'
import Ajv        from 'ajv'

//--------------------------------------------------------------------------------------------
//
// Setup Ajv validator with the following options and formats
//
//--------------------------------------------------------------------------------------------

const ajv = addFormats(new Ajv({}), [
  'date-time', 
  'time', 
  'date', 
  'email',  
  'hostname', 
  'ipv4', 
  'ipv6', 
  'uri', 
  'uri-reference', 
  'uuid',
  'uri-template', 
  'json-pointer', 
  'relative-json-pointer', 
  'regex'
])

//--------------------------------------------------------------------------------------------
//
// Create a TypeBox type
//
//--------------------------------------------------------------------------------------------

const T = Type.Object({
  x: Type.Number(),
  y: Type.Number(),
  z: Type.Number()
})

//--------------------------------------------------------------------------------------------
//
// Validate Data
//
//--------------------------------------------------------------------------------------------

const R = ajv.validate(T, { x: 1, y: 2, z: 3 })      // const R = true

Compiler

TypeBox provides an optional high performance just-in-time (JIT) compiler and type checker that can be used in applications that require extremely fast validation. Note that this compiler is optimized for TypeBox types only where the schematics are known in advance. If defining custom types with Type.Unsafe<T> please consider Ajv.

The compiler module is provided as an optional import.

import { TypeCompiler } from '@sinclair/typebox/compiler'

Use the Compile(...) function to compile a type.

const C = TypeCompiler.Compile(Type.Object({         // const C: TypeCheck<TObject<{
  x: Type.Number(),                                  //     x: TNumber;
  y: Type.Number(),                                  //     y: TNumber;
  z: Type.Number()                                   //     z: TNumber;
}))                                                  // }>>

const R = C.Check({ x: 1, y: 2, z: 3 })              // const R = true

Validation errors can be read with the Errors(...) function.

const C = TypeCompiler.Compile(Type.Object({         // const C: TypeCheck<TObject<{
  x: Type.Number(),                                  //     x: TNumber;
  y: Type.Number(),                                  //     y: TNumber;
  z: Type.Number()                                   //     z: TNumber;
}))                                                  // }>>

const value = { }

const errors = [...C.Errors(value)]                  // const errors = [{
                                                     //   schema: { type: 'number' },
                                                     //   path: '/x',
                                                     //   value: undefined,
                                                     //   message: 'Expected number'
                                                     // }, {
                                                     //   schema: { type: 'number' },
                                                     //   path: '/y',
                                                     //   value: undefined,
                                                     //   message: 'Expected number'
                                                     // }, {
                                                     //   schema: { type: 'number' },
                                                     //   path: '/z',
                                                     //   value: undefined,
                                                     //   message: 'Expected number'
                                                     // }]

Compiled routines can be inspected with the .Code() function.

const C = TypeCompiler.Compile(Type.String())        // const C: TypeCheck<TString>

console.log(C.Code())                                // return function check(value) {
                                                     //   return (
                                                     //     (typeof value === 'string')
                                                     //   )
                                                     // }

Formats

Use the format module to create user defined string formats. The format module is used by the Value and TypeCompiler modules only. If using Ajv, please refer to the official Ajv format documentation located here.

The format module is an optional import.

import { Format } from '@sinclair/typebox/format'

The following creates a palindrome string format.

Format.Set('palindrome', value => value === value.split('').reverse().join(''))

Once set, this format can then be used by the TypeCompiler and Value modules.

const T = Type.String({ format: 'palindrome' })

const A = TypeCompiler.Compile(T).Check('engine')    // const A = false

const B = Value.Check(T, 'kayak')                    // const B = true

Benchmark

This project maintains a set of benchmarks that measure Ajv, Value and TypeCompiler compilation and validation performance. These benchmarks can be run locally by cloning this repository and running npm run benchmark. The results below show for Ajv version 8.11.0.

For additional comparative benchmarks, please refer to typescript-runtime-type-benchmarks.

Compile

This benchmark measures compilation performance for varying types. You can review this benchmark here.

┌──────────────────┬────────────┬──────────────┬──────────────┬──────────────┐
     (index)       Iterations      Ajv       TypeCompiler  Performance  
├──────────────────┼────────────┼──────────────┼──────────────┼──────────────┤
           Number     2000     '    410 ms'  '     10 ms'  '   41.00 x' 
           String     2000     '    321 ms'  '      8 ms'  '   40.13 x' 
          Boolean     2000     '    314 ms'  '      6 ms'  '   52.33 x' 
             Null     2000     '    273 ms'  '      6 ms'  '   45.50 x' 
            RegEx     2000     '    485 ms'  '     11 ms'  '   44.09 x' 
          ObjectA     2000     '   2867 ms'  '     41 ms'  '   69.93 x' 
          ObjectB     2000     '   3018 ms'  '     30 ms'  '  100.60 x' 
            Tuple     2000     '   1298 ms'  '     21 ms'  '   61.81 x' 
            Union     2000     '   1340 ms'  '     23 ms'  '   58.26 x' 
          Vector4     2000     '   1794 ms'  '     22 ms'  '   81.55 x' 
          Matrix4     2000     '   1037 ms'  '     12 ms'  '   86.42 x' 
   Literal_String     2000     '    380 ms'  '      9 ms'  '   42.22 x' 
   Literal_Number     2000     '    446 ms'  '      8 ms'  '   55.75 x' 
  Literal_Boolean     2000     '    400 ms'  '      4 ms'  '  100.00 x' 
     Array_Number     2000     '    764 ms'  '      6 ms'  '  127.33 x' 
     Array_String     2000     '    785 ms'  '      9 ms'  '   87.22 x' 
    Array_Boolean     2000     '    796 ms'  '      6 ms'  '  132.67 x' 
    Array_ObjectA     2000     '   3678 ms'  '     34 ms'  '  108.18 x' 
    Array_ObjectB     2000     '   3875 ms'  '     34 ms'  '  113.97 x' 
      Array_Tuple     2000     '   2231 ms'  '     15 ms'  '  148.73 x' 
      Array_Union     2000     '   1713 ms'  '     18 ms'  '   95.17 x' 
    Array_Vector4     2000     '   2381 ms'  '     16 ms'  '  148.81 x' 
    Array_Matrix4     2000     '   1644 ms'  '     14 ms'  '  117.43 x' 
└──────────────────┴────────────┴──────────────┴──────────────┴──────────────┘

Validate

This benchmark measures validation performance for varying types. You can review this benchmark here.

┌──────────────────┬────────────┬──────────────┬──────────────┬──────────────┬──────────────┐
     (index)       Iterations   ValueCheck       Ajv       TypeCompiler  Performance  
├──────────────────┼────────────┼──────────────┼──────────────┼──────────────┼──────────────┤
           Number   1000000    '     29 ms'  '      6 ms'  '      5 ms'  '    1.20 x' 
           String   1000000    '     24 ms'  '     23 ms'  '     11 ms'  '    2.09 x' 
          Boolean   1000000    '     21 ms'  '     22 ms'  '     10 ms'  '    2.20 x' 
             Null   1000000    '     29 ms'  '     26 ms'  '     15 ms'  '    1.73 x' 
            RegEx   1000000    '    180 ms'  '     46 ms'  '     36 ms'  '    1.28 x' 
          ObjectA   1000000    '    548 ms'  '     36 ms'  '     24 ms'  '    1.50 x' 
          ObjectB   1000000    '    995 ms'  '     52 ms'  '     40 ms'  '    1.30 x' 
            Tuple   1000000    '    119 ms'  '     23 ms'  '     14 ms'  '    1.64 x' 
            Union   1000000    '    308 ms'  '     25 ms'  '     15 ms'  '    1.67 x' 
        Recursive   1000000    '   3405 ms'  '    458 ms'  '    214 ms'  '    2.14 x' 
          Vector4   1000000    '    144 ms'  '     23 ms'  '     12 ms'  '    1.92 x' 
          Matrix4   1000000    '    608 ms'  '     42 ms'  '     29 ms'  '    1.45 x' 
   Literal_String   1000000    '     46 ms'  '     21 ms'  '     10 ms'  '    2.10 x' 
   Literal_Number   1000000    '     48 ms'  '     20 ms'  '      9 ms'  '    2.22 x' 
  Literal_Boolean   1000000    '     50 ms'  '     20 ms'  '     10 ms'  '    2.00 x' 
     Array_Number   1000000    '    467 ms'  '     34 ms'  '     19 ms'  '    1.79 x' 
     Array_String   1000000    '    488 ms'  '     32 ms'  '     20 ms'  '    1.60 x' 
    Array_Boolean   1000000    '    476 ms'  '     34 ms'  '     24 ms'  '    1.42 x' 
    Array_ObjectA   1000000    '  14220 ms'  '   2819 ms'  '   1810 ms'  '    1.56 x' 
    Array_ObjectB   1000000    '  16344 ms'  '   3067 ms'  '   2147 ms'  '    1.43 x' 
      Array_Tuple   1000000    '   1702 ms'  '     92 ms'  '     71 ms'  '    1.30 x' 
      Array_Union   1000000    '   4754 ms'  '    249 ms'  '     89 ms'  '    2.80 x' 
  Array_Recursive   1000000    '  56465 ms'  '   6921 ms'  '   2411 ms'  '    2.87 x' 
    Array_Vector4   1000000    '   1974 ms'  '    109 ms'  '     55 ms'  '    1.98 x' 
    Array_Matrix4   1000000    '  10722 ms'  '    400 ms'  '    320 ms'  '    1.25 x' 
└──────────────────┴────────────┴──────────────┴──────────────┴──────────────┴──────────────┘

Compression

The following table lists esbuild compiled and minified sizes for each TypeBox module.

┌──────────────────────┬────────────┬────────────┬─────────────┐
       (index)          Compiled    Minified   Compression 
├──────────────────────┼────────────┼────────────┼─────────────┤
 typebox/compiler      '   48 kb'  '   24 kb'   '2.00 x'   
 typebox/conditional   '   41 kb'  '   16 kb'   '2.47 x'   
 typebox/format        '    0 kb'  '    0 kb'   '2.66 x'   
 typebox/guard         '   20 kb'  '    9 kb'   '2.08 x'   
 typebox/value         '   68 kb'  '   31 kb'   '2.15 x'   
 typebox               '   11 kb'  '    5 kb'   '1.91 x'   
└──────────────────────┴────────────┴────────────┴─────────────┘

Contribute

TypeBox is open to community contribution. Please ensure you submit an open issue before submitting your pull request. The TypeBox project preferences open community discussion prior to accepting new features.