Class GuardsContextCreator

packages/core/guards/guards-context-creator.ts:12–121

import { InstanceWrapper } from '../injector/instance-wrapper';

export class GuardsContextCreator extends ContextCreator {
  private moduleContext: string;

  constructor(
    private readonly container: NestContainer,
    private readonly config?: ApplicationConfig,
  ) {
    super();
  }

  public create(
    instance: Controller,
    callback: (...args: unknown[]) => unknown,
    module: string,
    contextId = STATIC_CONTEXT,
    inquirerId?: string,
  ): CanActivate[] {
    this.moduleContext = module;
    return this.createContext(
      instance,
      callback,
      GUARDS_METADATA,
      contextId,
      inquirerId,
    );
  }

  public createConcreteContext<T extends unknown[], R extends unknown[]>(
    metadata: T,
    contextId = STATIC_CONTEXT,
    inquirerId?: string,
  ): R {
    if (isEmpty(metadata)) {
      return [] as unknown[] as R;
    }
    return iterate(metadata)
      .filter((guard: any) => guard && (guard.name || guard.canActivate))
      .map(guard =>
        this.getGuardInstance(guard as Function, contextId, inquirerId),
      )
      .filter(
        (guard: CanActivate | null) => !!guard && isFunction(guard.canActivate),
      )
      .toArray() as R;
  }

  public getGuardInstance(
    metatype: Function | CanActivate,
    contextId = STATIC_CONTEXT,
    inquirerId?: string,
  ): CanActivate | null {
    const isObject = !!(metatype as CanActivate).canActivate;
    if (isObject) {
      return metatype as CanActivate;
    }
    const instanceWrapper = this.getInstanceByMetatype(
      metatype as Type<unknown>,
    );