feat(rabbitmq): adds consistent rabbitmq config

use community convention of forRoot and forRootAsync to bootstrap module

fix #34

packages/common/src/index.ts

@@ -1 +1,2 @@
 export * from './mixins';
+export * from './options';

packages/common/src/options.ts

@@ -0,0 +1,33 @@
+import { Type } from '@nestjs/common';
+import { ModuleMetadata, Provider } from '@nestjs/common/interfaces';
+
+export interface OptionsFactory<T> {
+  createOptions(): Promise<T> | T;
+}
+
+export interface AsyncOptionsFactoryProvider<T>
+  extends Pick<ModuleMetadata, 'imports'> {
+  useExisting?: Type<OptionsFactory<T>>;
+  useClass?: Type<OptionsFactory<T>>;
+  useFactory?: (...args: any[]) => Promise<T> | T;
+  inject?: any[];
+}
+
+export function createAsyncOptionsProvider<T>(
+  provide: string | symbol | Type<any>,
+  options: AsyncOptionsFactoryProvider<T>
+): Provider {
+  if (options.useFactory) {
+    return {
+      provide,
+      useFactory: options.useFactory,
+      inject: options.inject || []
+    };
+  }
+  return {
+    provide,
+    useFactory: async (optionsFactory: OptionsFactory<T>) =>
+      await optionsFactory.createOptions(),
+    inject: [options.useExisting || options.useClass]
+  };
+}

packages/rabbitmq/src/rabbitmq.constants.ts

@@ -1 +1,2 @@
 export const RABBIT_HANDLER = Symbol('RABBIT_HANDLER');
+export const RABBIT_CONFIG = Symbol('RABBIT_CONFIG');

packages/rabbitmq/src/rabbitmq.module.ts

@@ -1,9 +1,19 @@
 import { DiscoveryModule, DiscoveryService } from '@nestjs-plus/discovery';
-import { DynamicModule, Logger, Module, OnModuleInit } from '@nestjs/common';
+import {
+  DynamicModule,
+  Logger,
+  Module,
+  OnModuleInit,
+  Provider
+} from '@nestjs/common';
+import {
+  AsyncOptionsFactoryProvider,
+  createAsyncOptionsProvider
+} from '@nestjs-plus/common';
 import { ExternalContextCreator } from '@nestjs/core/helpers/external-context-creator';
 import { groupBy } from 'lodash';
 import { AmqpConnection } from './amqp/connection';
-import { RABBIT_HANDLER } from './rabbitmq.constants';
+import { RABBIT_HANDLER, RABBIT_CONFIG } from './rabbitmq.constants';
 import { RabbitHandlerConfig, RabbitMQConfig } from './rabbitmq.interfaces';
 
 @Module({
@@ -18,6 +28,36 @@ export class RabbitMQModule implements OnModuleInit {
     private readonly externalContextCreator: ExternalContextCreator
   ) {}
 
+  public static forRootAsync(
+    asyncOptionsFactoryProvider: AsyncOptionsFactoryProvider<RabbitMQConfig>
+  ): DynamicModule {
+    return {
+      module: RabbitMQModule,
+      exports: [AmqpConnection],
+      imports: asyncOptionsFactoryProvider.imports,
+      providers: this.createAsyncProviders(asyncOptionsFactoryProvider)
+    };
+  }
+
+  public static forRoot(config: RabbitMQConfig): DynamicModule {
+    return {
+      module: RabbitMQModule,
+      providers: [
+        {
+          provide: AmqpConnection,
+          useFactory: async (): Promise<AmqpConnection> => {
+            const connection = new AmqpConnection(config);
+            await connection.init();
+            const logger = new Logger(RabbitMQModule.name);
+            logger.log('Successfully connected to RabbitMQ');
+            return connection;
+          }
+        }
+      ],
+      exports: [AmqpConnection]
+    };
+  }
+
   public static build(config: RabbitMQConfig): DynamicModule {
     return {
       module: RabbitMQModule,
@@ -89,4 +129,30 @@ export class RabbitMQModule implements OnModuleInit {
       );
     }
   }
+
+  private static createAsyncProviders(
+    asyncOptionsFactoryProvider: AsyncOptionsFactoryProvider<RabbitMQConfig>
+  ): Provider[] {
+    const optionsProvider = createAsyncOptionsProvider(
+      RABBIT_CONFIG,
+      asyncOptionsFactoryProvider
+    );
+
+    if (
+      asyncOptionsFactoryProvider.useExisting ||
+      asyncOptionsFactoryProvider.useFactory
+    ) {
+      return [optionsProvider];
+    }
+
+    return asyncOptionsFactoryProvider.useClass
+      ? [
+          optionsProvider,
+          {
+            provide: asyncOptionsFactoryProvider.useClass,
+            useClass: asyncOptionsFactoryProvider.useClass
+          }
+        ]
+      : [];
+  }
 }

packages/rabbitmq/tsconfig.json

@@ -5,5 +5,5 @@
     "rootDir": "./src"
   },
   "include": ["./src"],
-  "references": [{ "path": "../discovery" }]
+  "references": [{ "path": "../discovery" }, { "path": "../common" }]
 }