From c498c646512c730ab1ca35b71450b3ba447e6ab0 Mon Sep 17 00:00:00 2001
From: Hage Yaapa <hage.yaapa@in.ibm.com>
Date: Fri, 4 Oct 2019 18:03:23 +0530
Subject: [PATCH] feat: add defineCrudRepositoryClass

Add `defineCrudRepositoryClass` - a helper to create named repository classes
---
 .../default-model-crud-rest.acceptance.ts     | 11 +++--
 .../unit/define-crud-repository-class.unit.ts | 22 ++++++++++
 packages/rest-crud/src/index.ts               |  1 +
 packages/rest-crud/src/repository-builder.ts  | 44 +++++++++++++++++++
 4 files changed, 72 insertions(+), 6 deletions(-)
 create mode 100644 packages/rest-crud/src/__tests__/unit/define-crud-repository-class.unit.ts
 create mode 100644 packages/rest-crud/src/repository-builder.ts

diff --git a/packages/rest-crud/src/__tests__/acceptance/default-model-crud-rest.acceptance.ts b/packages/rest-crud/src/__tests__/acceptance/default-model-crud-rest.acceptance.ts
index 3167ff0a746b..585dd00217c9 100644
--- a/packages/rest-crud/src/__tests__/acceptance/default-model-crud-rest.acceptance.ts
+++ b/packages/rest-crud/src/__tests__/acceptance/default-model-crud-rest.acceptance.ts
@@ -4,7 +4,6 @@
 // License text available at https://opensource.org/licenses/MIT
 
 import {
-  DefaultCrudRepository,
   Entity,
   EntityCrudRepository,
   juggler,
@@ -19,7 +18,7 @@ import {
   givenHttpServerConfig,
   toJSON,
 } from '@loopback/testlab';
-import {defineCrudRestController} from '../..';
+import {defineCrudRepositoryClass, defineCrudRestController} from '../..';
 
 // In this test scenario, we create a product with a required & an optional
 // property and use the default model settings (strict mode, forceId).
@@ -283,10 +282,10 @@ describe('CrudRestController for a simple Product model', () => {
 
   async function setupTestScenario() {
     const db = new juggler.DataSource({connector: 'memory'});
-    repo = new DefaultCrudRepository<Product, typeof Product.prototype.id>(
-      Product,
-      db,
-    );
+
+    const ProductRepository = defineCrudRepositoryClass(Product);
+
+    repo = new ProductRepository(db);
 
     const CrudRestController = defineCrudRestController<
       Product,
diff --git a/packages/rest-crud/src/__tests__/unit/define-crud-repository-class.unit.ts b/packages/rest-crud/src/__tests__/unit/define-crud-repository-class.unit.ts
new file mode 100644
index 000000000000..c8d0477b5c21
--- /dev/null
+++ b/packages/rest-crud/src/__tests__/unit/define-crud-repository-class.unit.ts
@@ -0,0 +1,22 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/rest-crud
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {Entity, model, property} from '@loopback/repository';
+import {expect} from '@loopback/testlab';
+import {defineCrudRepositoryClass} from '../..';
+
+describe('defineCrudRestController', () => {
+  it('should generate repository based on Model name', async () => {
+    @model()
+    class Product extends Entity {
+      @property({id: true})
+      id: number;
+    }
+
+    const ProductRepository = defineCrudRepositoryClass(Product);
+
+    expect(ProductRepository.name).to.equal('ProductRepository');
+  });
+});
diff --git a/packages/rest-crud/src/index.ts b/packages/rest-crud/src/index.ts
index a099ac3a456c..4a6f68f068e8 100644
--- a/packages/rest-crud/src/index.ts
+++ b/packages/rest-crud/src/index.ts
@@ -4,3 +4,4 @@
 // License text available at https://opensource.org/licenses/MIT
 
 export * from './crud-rest.controller';
+export * from './repository-builder';
diff --git a/packages/rest-crud/src/repository-builder.ts b/packages/rest-crud/src/repository-builder.ts
new file mode 100644
index 000000000000..70aa651ebbb8
--- /dev/null
+++ b/packages/rest-crud/src/repository-builder.ts
@@ -0,0 +1,44 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/rest-crud
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {
+  DefaultCrudRepository,
+  Entity,
+  EntityCrudRepository,
+  juggler,
+} from '@loopback/repository';
+import * as assert from 'assert';
+
+export function defineCrudRepositoryClass<
+  T extends Entity,
+  IdType,
+  Relations extends object = {}
+>(
+  entityClass: typeof Entity & {prototype: T},
+): RepositoryClass<T, IdType, Relations> {
+  const repoName = entityClass.name + 'Repository';
+  const defineNamedRepo = new Function(
+    'EntityCtor',
+    'BaseRepository',
+    `return class ${repoName} extends BaseRepository {
+      constructor(dataSource) {
+        super(EntityCtor, dataSource);
+      }
+    };`,
+  );
+
+  // TODO(bajtos) make DefaultCrudRepository configurable (?)
+  const repo = defineNamedRepo(entityClass, DefaultCrudRepository);
+  assert.equal(repo.name, repoName);
+  return repo;
+}
+
+export interface RepositoryClass<
+  T extends Entity,
+  IdType,
+  Relations extends object
+> {
+  new (ds: juggler.DataSource): EntityCrudRepository<T, IdType, Relations>;
+}