callModuleInitHook

Kind: Function

Source: packages/core/hooks/on-module-init.hook.ts

Part of: Core

Calls the onModuleInit function on the module and its children (providers / controllers).

callModuleInitHook runs the onModuleInit() lifecycle hook for a Nest module’s initialized controllers, providers, injectables, and middleware. It processes non-transient and transient instances before invoking the module class’s own hook when its dependency tree is static.

Signature

ts
async function callModuleInitHook(module: Module): Promise<void>

Parameters

Returns: Promise<void>

Diagram

mermaid
graph LR
  A[Module] --> B[Controllers]
  A --> C[Providers]
  A --> D[Injectables]
  A --> E[Middleware]

  B --> F[Invoke onModuleInit]
  C --> F
  D --> F
  E --> F

  F --> G[Non-transient instances]
  G --> H[Transient instances]
  H --> I[Module class onModuleInit]

Usage

ts
import { callModuleInitHook } from '@nestjs/core/hooks/on-module-init.hook';
import { Module } from '@nestjs/core/injector/module';

// Typically called internally by Nest during application initialization.
async function initializeModule(moduleRef: Module) {
  await callModuleInitHook(moduleRef);

  console.log('Module lifecycle hooks have completed.');
}

AI Coding Instructions

• Treat this as an internal lifecycle utility; application code should usually implement OnModuleInit rather than call this function directly.
• Ensure providers, controllers, injectables, and middleware are fully instantiated before invoking module initialization hooks.
• Preserve the ordering: execute child instance hooks before the module class’s own onModuleInit() hook.
• Keep transient and non-transient instance handling separate so each lifecycle hook is invoked for the correct resolved instances.
• Only invoke the module class hook when its dependency tree is static and the class implements onModuleInit().

Relationships

• IMPORTS → OnModuleInit
• IMPORTS → isFunction
• IMPORTS → isNil