getNonTransientInstances

Kind: Function

Source: packages/core/injector/helpers/transient-instances.ts

Part of: Core

Returns the instances which are not transient

getNonTransientInstances filters provider instance entries and returns only those whose scope is not Scope.TRANSIENT. It is used by the injector lifecycle to identify reusable or request-scoped providers while excluding providers that must be created for every injection.

Signature

ts
function getNonTransientInstances(instances: [InjectionToken, InstanceWrapper][]): InstanceWrapper[]

Parameters

Returns: InstanceWrapper[]

Diagram

mermaid
graph LR
  A[Provider instance entries] --> B[getNonTransientInstances]
  B --> C{scope is TRANSIENT?}
  C -->|Yes| D[Exclude entry]
  C -->|No| E[Return entry]
  E --> F[Default and request-scoped providers]

Usage

ts
import { Scope } from '@nestjs/common';
import { getNonTransientInstances } from '@nestjs/core/injector/helpers/transient-instances';
import { InstanceWrapper } from '@nestjs/core/injector/instance-wrapper';

const providerEntries: [string, InstanceWrapper][] = [
  ['CacheService', { scope: Scope.DEFAULT } as InstanceWrapper],
  ['RequestContext', { scope: Scope.REQUEST } as InstanceWrapper],
  ['AuditService', { scope: Scope.TRANSIENT } as InstanceWrapper],
];

const nonTransientProviders = getNonTransientInstances(providerEntries);

// Includes CacheService and RequestContext.
// Excludes AuditService.
console.log(nonTransientProviders.map(([token]) => token));

AI Coding Instructions

• Pass provider entries as [token, InstanceWrapper] tuples, typically from a module provider map via Array.from(providers.entries()).
• Treat Scope.TRANSIENT providers as per-injection instances; do not include them in reuse, preload, or static lifecycle processing.
• Preserve the original tuple structure so downstream injector code can access both the provider token and its wrapper.
• Use this helper alongside transient-specific filtering helpers instead of duplicating scope checks throughout injector code.