Method toProvider

packages/context/src/binding.ts:847–866

* Bind the key to a value computed by a Provider. * * * @example * * ```ts * export class DateProvider implements Provider { * constructor(@inject('stringDate') private param: String){} * value(): Date { * return new Date(param); * } * } * ``` *

(providerClass: Constructor<Provider<T>>)

   * @param provider - The value provider to use.
   */
  toProvider(providerClass: Constructor<Provider<T>>): this {
    /* istanbul ignore if */
    if (debug.enabled) {
      debug('Bind %s to provider %s', this.key, providerClass.name);
    }
    this._source = {
      type: BindingType.PROVIDER,
      value: providerClass,
    };
    this._setValueGetter(resolutionCtx => {
      const providerOrPromise = instantiateClass<Provider<T>>(
        providerClass,
        resolutionCtx.context,
        resolutionCtx.options.session,
      );
      const value = transformValueOrPromise(providerOrPromise, p => p.value());
      return Binding.valueOrProxy(resolutionCtx, value);
    });
    return this;
  }

  /**
   * Bind the key to an instance of the given class.