Merge pull request #7439 from cmpadden/create-app-path-option

Support optional [path] argument in create-app command-line utility

.changeset/neat-rings-protect.md

@@ -0,0 +1,5 @@
+---
+'@backstage/create-app': patch
+---
+
+Support optional path argument when generating a project using `create-app`

packages/create-app/src/createApp.ts

@@ -27,7 +27,7 @@ import { Task, templatingTask } from './lib/tasks';
 
 const exec = promisify(execCb);
 
-async function checkExists(rootDir: string, name: string) {
+async function checkAppExists(rootDir: string, name: string) {
   await Task.forItem('checking', name, async () => {
     const destination = resolvePath(rootDir, name);
 
@@ -40,6 +40,17 @@ async function checkExists(rootDir: string, name: string) {
   });
 }
 
+async function checkPathExists(path: string) {
+  await Task.forItem('checking', path, async () => {
+    try {
+      await fs.mkdirs(path);
+    } catch (error) {
+      // will fail if a file already exists at given `path`
+      throw new Error(`Failed to create app directory: ${error.message}`);
+    }
+  });
+}
+
 async function createTemporaryAppFolder(tempDir: string) {
   await Task.forItem('creating', 'temporary directory', async () => {
     try {
@@ -50,12 +61,6 @@ async function createTemporaryAppFolder(tempDir: string) {
   });
 }
 
-async function cleanUp(tempDir: string) {
-  await Task.forItem('remove', 'temporary directory', async () => {
-    await fs.remove(tempDir);
-  });
-}
-
 async function buildApp(appDir: string) {
   const runCmd = async (cmd: string) => {
     await Task.forItem('executing', cmd, async () => {
@@ -75,11 +80,17 @@ async function buildApp(appDir: string) {
 
 async function moveApp(tempDir: string, destination: string, id: string) {
   await Task.forItem('moving', id, async () => {
-    await fs.move(tempDir, destination).catch(error => {
-      throw new Error(
-        `Failed to move app from ${tempDir} to ${destination}: ${error.message}`,
-      );
-    });
+    await fs
+      .move(tempDir, destination)
+      .catch(error => {
+        throw new Error(
+          `Failed to move app from ${tempDir} to ${destination}: ${error.message}`,
+        );
+      })
+      .finally(() => {
+        // remove temporary files on both success and failure
+        fs.removeSync(tempDir);
+      });
   });
 }
 
@@ -117,23 +128,40 @@ export default async (cmd: Command): Promise<void> => {
 
   const templateDir = paths.resolveOwn('templates/default-app');
   const tempDir = resolvePath(os.tmpdir(), answers.name);
-  const appDir = resolvePath(paths.targetDir, answers.name);
+
+  // Use `--path` argument as applicaiton directory when specified, otherwise
+  // create a directory using `answers.name`
+  const appDir = cmd.path
+    ? resolvePath(paths.targetDir, cmd.path)
+    : resolvePath(paths.targetDir, answers.name);
 
   Task.log();
   Task.log('Creating the app...');
 
   try {
-    Task.section('Checking if the directory is available');
-    await checkExists(paths.targetDir, answers.name);
+    if (cmd.path) {
+      // Template directly to specified path
 
-    Task.section('Creating a temporary app directory');
-    await createTemporaryAppFolder(tempDir);
+      Task.section('Checking that supplied path exists');
+      await checkPathExists(appDir);
 
-    Task.section('Preparing files');
-    await templatingTask(templateDir, tempDir, answers);
+      Task.section('Preparing files');
+      await templatingTask(templateDir, cmd.path, answers);
+    } else {
+      // Template to temporary location, and then move files
 
-    Task.section('Moving to final location');
-    await moveApp(tempDir, appDir, answers.name);
+      Task.section('Checking if the directory is available');
+      await checkAppExists(paths.targetDir, answers.name);
+
+      Task.section('Creating a temporary app directory');
+      await createTemporaryAppFolder(tempDir);
+
+      Task.section('Preparing files');
+      await templatingTask(templateDir, tempDir, answers);
+
+      Task.section('Moving to final location');
+      await moveApp(tempDir, appDir, answers.name);
+    }
 
     if (!cmd.skipInstall) {
       Task.section('Building the app');
@@ -157,10 +185,7 @@ export default async (cmd: Command): Promise<void> => {
     Task.error(String(error));
 
     Task.log('It seems that something went wrong when creating the app 🤔');
-    Task.log('We are going to clean up, and then you can try again.');
 
-    Task.section('Cleanup');
-    await cleanUp(tempDir);
     Task.error('🔥  Failed to create app!');
     Task.exit(1);
   }

packages/create-app/src/index.ts

@@ -26,10 +26,14 @@ import { version } from '../package.json';
 import createApp from './createApp';
 
 const main = (argv: string[]) => {
-  program.name('backstage-create-app').version(version);
-
   program
-    .description('Creates a new app in a new directory')
+    .name('backstage-create-app')
+    .version(version)
+    .description('Creates a new app in a new directory or specified path')
+    .option(
+      '--path [directory]',
+      'Location to store the app defaulting to a new folder with the app name',
+    )
     .option(
       '--skip-install',
       'Skip the install and builds steps after creating the app',