From 589860ec27f7fbe2cb96e5266737850a6c2c5ead Mon Sep 17 00:00:00 2001
From: Alper Altay <alper.altay@lego.com>
Date: Mon, 24 Jun 2024 15:26:53 +0200
Subject: [PATCH] feat: add plugin to backend index.ts

Signed-off-by: Alper Altay <alper.altay@lego.com>
---
 .../lib/new/factories/backendPlugin.test.ts   | 88 ++++++++++++++++++-
 .../src/lib/new/factories/backendPlugin.ts    | 34 +++++++
 2 files changed, 119 insertions(+), 3 deletions(-)

diff --git a/packages/cli/src/lib/new/factories/backendPlugin.test.ts b/packages/cli/src/lib/new/factories/backendPlugin.test.ts
index c5930592a3..c6196d8690 100644
--- a/packages/cli/src/lib/new/factories/backendPlugin.test.ts
+++ b/packages/cli/src/lib/new/factories/backendPlugin.test.ts
@@ -26,13 +26,19 @@ import {
 import { backendPlugin } from './backendPlugin';
 import { createMockDirectory } from '@backstage/backend-test-utils';
 
+const backendIndexTsContent = `
+import { createBackend } from '@backstage/backend-defaults';  
+  
+const backend = createBackend();  
+  
+backend.start();
+`;
+
 describe('backendPlugin factory', () => {
   const mockDir = createMockDirectory();
 
   beforeEach(() => {
-    mockPaths({
-      targetRoot: mockDir.path,
-    });
+    mockPaths({ targetRoot: mockDir.path });
   });
 
   afterEach(() => {
@@ -44,6 +50,9 @@ describe('backendPlugin factory', () => {
       packages: {
         backend: {
           'package.json': JSON.stringify({}),
+          src: {
+            'index.ts': backendIndexTsContent,
+          },
         },
       },
       plugins: {},
@@ -89,6 +98,7 @@ describe('backendPlugin factory', () => {
       'Installing:',
       `moving        plugins${sep}test-backend`,
       'backend       adding dependency',
+      'backend       adding import and plugin',
     ]);
 
     await expect(
@@ -99,6 +109,78 @@ describe('backendPlugin factory', () => {
       },
     });
 
+    await expect(
+      fs.readFile(mockDir.resolve('packages/backend/src/index.ts'), 'utf8'),
+    ).resolves.toBe(`
+import { createBackend } from '@backstage/backend-defaults';  
+
+const backend = createBackend();  
+  
+backend.add(import("backstage-plugin-test-backend"));  
+backend.start();
+`);
+
+    expect(Task.forCommand).toHaveBeenCalledTimes(2);
+    expect(Task.forCommand).toHaveBeenCalledWith('yarn install', {
+      cwd: mockDir.resolve('plugins/test-backend'),
+      optional: true,
+    });
+    expect(Task.forCommand).toHaveBeenCalledWith('yarn lint --fix', {
+      cwd: mockDir.resolve('plugins/test-backend'),
+      optional: true,
+    });
+  });
+
+  it('should create a backend plugin with more options and codeowners', async () => {
+    mockDir.setContent({
+      CODEOWNERS: '',
+      packages: {
+        backend: {
+          'package.json': JSON.stringify({}),
+          src: {
+            'index.ts': backendIndexTsContent,
+          },
+        },
+      },
+      plugins: {},
+    });
+
+    const options = await FactoryRegistry.populateOptions(backendPlugin, {
+      id: 'test',
+      owner: '@test-user',
+    });
+
+    const [, mockStream] = createMockOutputStream();
+    jest.spyOn(process, 'stderr', 'get').mockReturnValue(mockStream);
+    jest.spyOn(Task, 'forCommand').mockResolvedValue();
+
+    await backendPlugin.create(options, {
+      scope: 'internal',
+      private: true,
+      isMonoRepo: true,
+      defaultVersion: '1.0.0',
+      markAsModified: () => {},
+      createTemporaryDirectory: () => fs.mkdtemp('test'),
+    });
+
+    await expect(
+      fs.readJson(mockDir.resolve('packages/backend/package.json')),
+    ).resolves.toEqual({
+      dependencies: {
+        '@internal/backstage-plugin-test-backend': '^1.0.0',
+      },
+    });
+
+    await expect(
+      fs.readFile(mockDir.resolve('packages/backend/src/index.ts'), 'utf8'),
+    ).resolves.toBe(`
+import { createBackend } from '@backstage/backend-defaults';  
+  
+const backend = createBackend();  
+  
+backend.add(import("@internal/backstage-plugin-test-backend"));  
+backend.start();`);
+
     expect(Task.forCommand).toHaveBeenCalledTimes(2);
     expect(Task.forCommand).toHaveBeenCalledWith('yarn install', {
       cwd: mockDir.resolve('plugins/test-backend'),
diff --git a/packages/cli/src/lib/new/factories/backendPlugin.ts b/packages/cli/src/lib/new/factories/backendPlugin.ts
index 09ea98fbe7..06bc6bd366 100644
--- a/packages/cli/src/lib/new/factories/backendPlugin.ts
+++ b/packages/cli/src/lib/new/factories/backendPlugin.ts
@@ -78,6 +78,40 @@ export const backendPlugin = createFactory<Options>({
           },
         );
       });
+
+      await Task.forItem('backend', 'adding import and plugin', async () => {
+        const backendFilePath = paths.resolveTargetRoot(
+          'packages/backend/src/index.ts',
+        );
+        if (!(await fs.pathExists(backendFilePath))) {
+          return;
+        }
+        const content = await fs.readFile(backendFilePath, 'utf8');
+        const revLines = content.split('\n').reverse();
+
+        const lastImportIndex = revLines.findIndex(line =>
+          line.match(/ from ("|').*("|')/),
+        );
+        const lastBackendAddIndex = revLines.findIndex(line =>
+          line.match(/backend.add/),
+        );
+
+        const backendAddLine = `backend.add(import("${name}"));`;
+
+        if (lastImportIndex !== -1 && lastBackendAddIndex !== -1) {
+          if (!content.includes(backendAddLine)) {
+            const [indentation] =
+              revLines[lastBackendAddIndex + 1].match(/^\s*/) ?? [];
+            revLines.splice(
+              lastBackendAddIndex + 1,
+              0,
+              indentation + backendAddLine,
+            );
+          }
+          const newContent = revLines.reverse().join('\n');
+          await fs.writeFile(backendFilePath, newContent, 'utf8');
+        }
+      });
     }
 
     if (options.owner) {