nexus/src/dynamicMethod.ts

Scalable, strongly typed GraphQL schema development

import type { PluginBuilderLens } from './builder'
import type { InputDefinitionBlock, OutputDefinitionBlock } from './definitions/definitionBlocks'
import { NexusTypes, withNexusSymbol } from './definitions/_types'
import type { NexusWrapKind } from './definitions/wrapping'

export type OutputFactoryConfig<T> = {
  /** The name of the type this field is being declared on */
  typeName: string
  stage: 'walk' | 'build'
  args: any[]
  builder: PluginBuilderLens
  typeDef: OutputDefinitionBlock<any>
  /** The list of chained wrapping calls leading up to this dynamic method */
  wrapping?: NexusWrapKind[]
}

export type InputFactoryConfig<T> = {
  args: any[]
  builder: PluginBuilderLens
  typeDef: InputDefinitionBlock<any>
  /** The name of the type this field is being declared on */
  typeName: string
  /** The list of chained wrapping calls leading up to this dynamic method */
  wrapping?: NexusWrapKind[]
}

export interface BaseExtensionConfig<T extends string> {
  /** The name of the "extension", the field made available on the builders */
  name: T
  /** The full type definition for the options, including generic signature for the type */
  typeDefinition?: string
  /** Description inserted above the typeDefinition for the field, will be formatted as JSDOC by Nexus */
  typeDescription?: string
}

export interface DynamicOutputMethodConfig<T extends string> extends BaseExtensionConfig<T> {
  /** Invoked when the field is called */
  factory(config: OutputFactoryConfig<T>): any
}

export interface DynamicInputMethodConfig<T extends string> extends BaseExtensionConfig<T> {
  /** Invoked when the field is called */
  factory(config: InputFactoryConfig<T>): any
}

export class DynamicInputMethodDef<Name extends string> {
  constructor(readonly name: Name, protected config: DynamicInputMethodConfig<Name>) {}
  get value() {
    return this.config
  }
}
withNexusSymbol(DynamicInputMethodDef, NexusTypes.DynamicInput)

export class DynamicOutputMethodDef<Name extends string> {
  constructor(readonly name: Name, protected config: DynamicOutputMethodConfig<Name>) {}
  get value() {
    return this.config
  }
}
withNexusSymbol(DynamicOutputMethodDef, NexusTypes.DynamicOutputMethod)

/**
 * Defines a new property on the object definition block for an output type, taking arbitrary input to define
 * additional types. See the connectionPlugin:
 *
 * T.connectionField('posts', { nullable: true, totalCount(root, args, ctx, info) { return
 * ctx.user.getTotalPostCount(root.id, args) }, nodes(root, args, ctx, info) { return
 * ctx.user.getPosts(root.id, args) } })
 */
export function dynamicOutputMethod<T extends string>(config: DynamicOutputMethodConfig<T>) {
  return new DynamicOutputMethodDef(config.name, config)
}

/** Same as the outputFieldExtension, but for fields that should be added on as input types. */
export function dynamicInputMethod<T extends string>(config: DynamicInputMethodConfig<T>) {
  return new DynamicInputMethodDef(config.name, config)
}