Implementation:Langgenius Dify InputVar Types

Knowledge Sources	Dify
Domains	Workflow, DAG, Frontend
Last Updated	2026-02-12 00:00 GMT

Overview

Description

The InputVar Types implementation defines the TypeScript type system for workflow input variables in the Dify frontend. It consists of three key constructs: the InputVarType enum for user-facing form field types, the VarType enum for runtime variable types, and the ValueSelector type alias for path-based variable references. Together, these types form the backbone of the workflow's data model, enabling type-safe variable definition, wiring, and validation across the DAG.

Usage

These types are imported throughout the workflow component tree. InputVarType is used when configuring Start node form fields and when rendering input panels for single-node test runs. VarType is used for type-checking variable connections between nodes. ValueSelector is used whenever a node needs to reference an upstream node's output.

Code Reference

Source Location

web/app/components/workflow/types.ts, lines 151-234 (InputVarType: lines 196-211, VarType: lines 281-297, ValueSelector: line 151, Variable: lines 153-167).

Signature

// Path-based variable reference: [nodeId, key | obj key path]
export type ValueSelector = string[]

// User-facing input form field types
export enum InputVarType {
  textInput = 'text-input',
  paragraph = 'paragraph',
  select = 'select',
  number = 'number',
  url = 'url',
  files = 'files',
  json = 'json',              // object or array
  jsonObject = 'json_object', // only object, supports JSON schema
  contexts = 'contexts',      // knowledge retrieval
  iterator = 'iterator',      // iteration input
  singleFile = 'file',
  multiFiles = 'file-list',
  loop = 'loop',              // loop input
  checkbox = 'checkbox',
}

// Runtime variable data types
export enum VarType {
  string = 'string',
  number = 'number',
  integer = 'integer',
  secret = 'secret',
  boolean = 'boolean',
  object = 'object',
  file = 'file',
  array = 'array',
  arrayString = 'array[string]',
  arrayNumber = 'array[number]',
  arrayObject = 'array[object]',
  arrayBoolean = 'array[boolean]',
  arrayFile = 'array[file]',
  any = 'any',
  arrayAny = 'array[any]',
}

// Variable definition combining name, selector, and type
export type Variable = {
  variable: string
  label?: string | {
    nodeType: BlockEnum
    nodeName: string
    variable: string
  }
  value_selector: ValueSelector
  value_type?: VarType
  variable_type?: VarKindType
  value?: string
  options?: string[]
  required?: boolean
  isParagraph?: boolean
}

// Input variable for form rendering
export type InputVar = {
  type: InputVarType
  label: string | {
    nodeType: BlockEnum
    nodeName: string
    variable: string
    isChatVar?: boolean
  }
  variable: string
  max_length?: number
  default?: string | number
  required: boolean
  hint?: string
  options?: string[]
  value_selector?: ValueSelector
  placeholder?: string
  unit?: string
  json_schema?: string | Record<string, any>
} & Partial<UploadFileSetting>

Import

import {
  InputVarType,
  VarType,
  type ValueSelector,
  type Variable,
  type InputVar,
} from '@/app/components/workflow/types'

I/O Contract

Inputs (InputVarType enum values)

Enum Key	String Value	Description
textInput	'text-input'	Single-line text input field
paragraph	'paragraph'	Multi-line text area
select	'select'	Dropdown selection from predefined options
number	'number'	Numeric input field
url	'url'	URL input with validation
files	'files'	Multiple file upload
json	'json'	Raw JSON input (object or array)
jsonObject	'json_object'	JSON object with schema validation
contexts	'contexts'	Knowledge retrieval context input
iterator	'iterator'	Iteration node input
singleFile	'file'	Single file upload
multiFiles	'file-list'	File list upload
loop	'loop'	Loop node input
checkbox	'checkbox'	Boolean checkbox

Outputs (VarType enum values)

Enum Key	String Value	Description
string	'string'	Text data
number	'number'	Floating-point number
integer	'integer'	Integer number
secret	'secret'	Sensitive/masked value
boolean	'boolean'	True/false value
object	'object'	Key-value object
file	'file'	Single file reference
array	'array'	Untyped array
arrayString	'array[string]'	Array of strings
arrayNumber	'array[number]'	Array of numbers
arrayObject	'array[object]'	Array of objects
arrayBoolean	'array[boolean]'	Array of booleans
arrayFile	'array[file]'	Array of files
any	'any'	Any type (escape hatch)
arrayAny	'array[any]'	Array of any type

Usage Examples

import { InputVarType, VarType, type ValueSelector } from '@/app/components/workflow/types'

// Define a Start node input variable
const userQueryInput: InputVar = {
  type: InputVarType.textInput,
  label: 'User Query',
  variable: 'query',
  required: true,
  max_length: 2000,
  placeholder: 'Enter your question...',
}

// Wire an upstream node output to a downstream node input
const valueRef: ValueSelector = ['start-node-id', 'query']

// Declare a variable with runtime type
const outputVar: Variable = {
  variable: 'result',
  value_selector: ['llm-node-id', 'text'],
  value_type: VarType.string,
}

Related Pages

• Principle:Langgenius_Dify_Input_Variable_Definition