cli: add utility for passing explicit role option

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

packages/cli/src/commands/bundle/command.ts

@@ -14,19 +14,13 @@
  * limitations under the License.
  */
 
-import fs from 'fs-extra';
 import { Command } from 'commander';
-import { paths } from '../../lib/paths';
-import { readPackageRole } from '../../lib/role/packageRoles';
 import { bundleApp } from './bundleApp';
 import { bundleBackend } from './bundleBackend';
+import { readRoleForCommand } from '../../lib/role';
 
 export async function command(cmd: Command): Promise<void> {
-  const pkg = await fs.readJson(paths.resolveTarget('package.json'));
-  const roleInfo = readPackageRole(pkg);
-  if (!roleInfo) {
-    throw new Error(`Target package must have 'backstage.role' set`);
-  }
+  const roleInfo = await readRoleForCommand(cmd);
 
   const options = {
     configPaths: cmd.config as string[],

packages/cli/src/commands/index.ts

@@ -136,6 +136,8 @@ export function registerCommands(program: CommanderStatic) {
   program
     .command('bundle')
     .description('Bundle a package for deployment')
+    .option(...configOption)
+    .option('--role <name>', 'Run the command with an explicit package role')
     .option(
       '--skip-build-dependencies',
       'Skip the automatic building of local dependencies',
@@ -144,7 +146,6 @@ export function registerCommands(program: CommanderStatic) {
       '--stats',
       'If bundle stats are available, write them to the output directory',
     )
-    .option(...configOption)
     .action(lazy(() => import('./bundle').then(m => m.command)));
 
   program

packages/cli/src/lib/role/index.ts

@@ -21,6 +21,7 @@ export type {
 } from './types';
 export {
   getRoleInfo,
-  detectPackageRole,
   readPackageRole,
+  readRoleForCommand,
+  detectPackageRole,
 } from './packageRoles';

packages/cli/src/lib/role/packageRoles.test.ts

@@ -14,9 +14,12 @@
  * limitations under the License.
  */
 
+import mockFs from 'mock-fs';
+import { Command } from 'commander';
 import {
   getRoleInfo,
   readPackageRole,
+  readRoleForCommand,
   detectPackageRole,
 } from './packageRoles';
 
@@ -78,6 +81,47 @@ describe('readPackageRole', () => {
   });
 });
 
+describe('readRoleForCommand', () => {
+  function mkCommand(args: string) {
+    return new Command()
+      .option('--role <role>', 'test role')
+      .parse(['node', 'entry.js', ...args.split(' ')]) as Command;
+  }
+
+  beforeEach(() => {
+    mockFs({
+      'package.json': JSON.stringify({
+        name: 'test',
+        backstage: {
+          role: 'web-library',
+        },
+      }),
+    });
+  });
+
+  afterEach(() => {
+    mockFs.restore();
+  });
+
+  it('provides role info by role', async () => {
+    await expect(readRoleForCommand(mkCommand(''))).resolves.toEqual({
+      role: 'web-library',
+      platform: 'web',
+    });
+
+    await expect(
+      readRoleForCommand(mkCommand('--role node-library')),
+    ).resolves.toEqual({
+      role: 'node-library',
+      platform: 'node',
+    });
+
+    await expect(
+      readRoleForCommand(mkCommand('--role invalid')),
+    ).rejects.toThrow(`Unknown package role 'invalid'`);
+  });
+});
+
 describe('detectPackageRole', () => {
   it('detects the role of example-app', () => {
     expect(

packages/cli/src/lib/role/packageRoles.ts

@@ -15,6 +15,9 @@
  */
 
 import { z } from 'zod';
+import fs from 'fs-extra';
+import { Command } from 'commander';
+import { paths } from '../paths';
 import { PackageRoleInfo } from './types';
 
 const packageRoles: PackageRoleInfo[] = [
@@ -66,6 +69,21 @@ export function readPackageRole(pkgJson: unknown): PackageRoleInfo | undefined {
   return undefined;
 }
 
+export async function readRoleForCommand(
+  cmd: Command,
+): Promise<PackageRoleInfo> {
+  if (cmd.role) {
+    return getRoleInfo(cmd.role);
+  }
+
+  const pkg = await fs.readJson(paths.resolveTarget('package.json'));
+  const info = readPackageRole(pkg);
+  if (!info) {
+    throw new Error(`Target package must have 'backstage.role' set`);
+  }
+  return info;
+}
+
 const detectionSchema = z.object({
   name: z.string().optional(),
   scripts: z