feat: allow registering admin entities inside their own module

src/admin-resource.module.ts

@@ -0,0 +1,45 @@
+import { Module, DynamicModule } from '@nestjs/common';
+import { ResourceWithOptions } from 'adminjs'
+
+import AdminResourceService from './admin-resource.service';
+
+/**
+ * Nest module which is responsible for admin resources
+ * 
+ * @summary Nest Module
+ * 
+ * @class
+ * @name module:@adminjs/nestjs~AdminResourceModule
+ * @alias AdminResourceModule
+ * @memberof module:@adminjs/nestjs
+ */
+@Module({})
+export class AdminResourceModule {
+  /** 
+   * Register resources
+   * 
+   * @param {(ResourceWithOptions | any)[]} resources
+   * @memberof module:@adminjs/nestjs~AdminResourceModule
+   * @method
+   * @name forFeature
+   * @example
+   * import { Module } from '@nestjs/common';
+   * import { AdminResourceModule } from '@adminjs/nestjs';
+   * import { User } from './user.entity';
+   * 
+   * \@Module({
+   *   imports: [
+   *     AdminResourceModule.forFeature([User]),
+   *   ],
+   * })
+   * export class UserModule {}
+   * 
+   */
+  public static forFeature(resources: (ResourceWithOptions | any)[]): DynamicModule {
+    AdminResourceService.add(resources)
+
+    return {
+      module: AdminResourceModule,
+    };
+  }
+}

src/admin-resource.service.ts

@@ -0,0 +1,22 @@
+import { Injectable } from '@nestjs/common';
+import { ResourceWithOptions } from 'adminjs';
+
+@Injectable()
+class AdminResourceService {
+  private static resources: Set<ResourceWithOptions | any> = new Set();
+
+  public static add(resources: (ResourceWithOptions | any)[]) {
+    for (const resource of resources) {
+      if (AdminResourceService.resources.has(resource)) {
+        return;
+      }
+      AdminResourceService.resources.add(resource);
+    }
+  }
+
+  public static getResources() {
+    return Array.from(AdminResourceService.resources);
+  }
+}
+
+export default AdminResourceService;

src/admin.module.ts

@@ -8,6 +8,7 @@ import { AbstractLoader } from './loaders/abstract.loader'
 import { AdminModuleOptions } from './interfaces/admin-module-options.interface'
 import { AdminModuleFactory } from './interfaces/admin-module-factory.interface'
 import { CustomLoader } from './interfaces/custom-loader.interface'
+import AdminResourceService from './admin-resource.service'
 
 /**
  * Nest module which is responsible for an AdminJS integration
@@ -126,7 +127,13 @@ export class AdminModule implements OnModuleInit {
       return;
     }
 
-    const admin = new AdminJS(this.adminModuleOptions.adminJsOptions);
+    const forFeatureResources = AdminResourceService.getResources()
+
+    const adminJSOptions = forFeatureResources.length > 0
+      ? { ...this.adminModuleOptions.adminJsOptions, resources: forFeatureResources }
+      : this.adminModuleOptions.adminJsOptions
+
+    const admin = new AdminJS(adminJSOptions);
 
     const { httpAdapter } = this.httpAdapterHost;
     this.loader.register(admin, httpAdapter, { 

src/index.ts

@@ -213,6 +213,7 @@
 import * as NestJSPlugin from './admin.module'
 
 export * from './admin.module';
+export * from './admin-resource.module';
 export default NestJSPlugin;
 export * from './interfaces/admin-module-factory.interface';
 export * from './interfaces/admin-module-options.interface';