feat(): add asProvider helper method to config namespaces

.npmignore

@@ -6,11 +6,15 @@ package-lock.json
 tslint.json
 tsconfig.json
 .prettierrc
+.commitlintrc.json
+.eslintignore
+.eslintrc.js
 
 # github
 .github
 CONTRIBUTING.md
 renovate.json
+.release-it.json
 
 # ci
 .circleci

lib/config.constants.ts

@@ -9,3 +9,4 @@ export const VALIDATED_ENV_LOADER = 'VALIDATED_ENV_LOADER';
 export const PARTIAL_CONFIGURATION_KEY = 'PARTIAL_CONFIGURATION_KEY';
 export const PARTIAL_CONFIGURATION_PROPNAME = 'KEY';
 export const VALIDATED_ENV_PROPNAME = '_PROCESS_ENV_VALIDATED';
+export const AS_PROVIDER_METHOD_KEY = 'asProvider';

lib/utils/register-as.util.ts

@@ -1,32 +1,47 @@
+import { ConfigModule } from '..';
 import {
+  AS_PROVIDER_METHOD_KEY,
   PARTIAL_CONFIGURATION_KEY,
   PARTIAL_CONFIGURATION_PROPNAME,
 } from '../config.constants';
 import { ConfigFactory } from '../interfaces';
 import { ConfigObject } from '../types';
 import { getConfigToken } from './get-config-token.util';
 
-export type ConfigFactoryKeyHost = { KEY: string };
+export interface ConfigFactoryKeyHost<T = unknown> {
+  KEY: string;
+  asProvider(): {
+    imports: [ReturnType<typeof ConfigModule.forFeature>];
+    useFactory: (config: T) => T;
+    inject: [string];
+  };
+}
 
 /**
  * Registers the configuration object behind a specified token.
  */
 export function registerAs<
   TConfig extends ConfigObject,
-  TFactory extends ConfigFactory = ConfigFactory<TConfig>
->(token: string, configFactory: TFactory): TFactory & ConfigFactoryKeyHost {
-  Object.defineProperty(configFactory, PARTIAL_CONFIGURATION_KEY, {
-    configurable: false,
-    enumerable: false,
-    value: token,
-    writable: false,
-  });
-  Object.defineProperty(configFactory, PARTIAL_CONFIGURATION_PROPNAME, {
-    configurable: false,
-    enumerable: false,
-    value: getConfigToken(token),
-    writable: false,
-  });
+  TFactory extends ConfigFactory = ConfigFactory<TConfig>,
+>(
+  token: string,
+  configFactory: TFactory,
+): TFactory & ConfigFactoryKeyHost<ReturnType<TFactory>> {
+  const defineProperty = (key: string, value: unknown) => {
+    Object.defineProperty(configFactory, key, {
+      configurable: false,
+      enumerable: false,
+      value,
+      writable: false,
+    });
+  };
 
-  return configFactory as TFactory & ConfigFactoryKeyHost;
+  defineProperty(PARTIAL_CONFIGURATION_KEY, token);
+  defineProperty(PARTIAL_CONFIGURATION_PROPNAME, getConfigToken(token));
+  defineProperty(AS_PROVIDER_METHOD_KEY, () => ({
+    imports: [ConfigModule.forFeature(configFactory)],
+    useFactory: (config: unknown) => config,
+    inject: [getConfigToken(token)],
+  }));
+  return configFactory as TFactory & ConfigFactoryKeyHost<ReturnType<TFactory>>;
 }

tests/src/app.module.ts

@@ -1,5 +1,5 @@
-import Joi from 'joi';
 import { DynamicModule, Inject, Module, Optional } from '@nestjs/common';
+import Joi from 'joi';
 import { join } from 'path';
 import { ConfigType } from '../../lib';
 import { ConfigModule } from '../../lib/config.module';