From c36ac9742b2101c89df86b208b70eef23c56f215 Mon Sep 17 00:00:00 2001
From: Patrik Oldsberg <poldsberg@gmail.com>
Date: Sun, 6 Apr 2025 11:31:02 +0200
Subject: [PATCH] cli: repo start partial parsing of script options

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>
---
 .../src/modules/build/lib/bundler/server.ts   |  1 +
 packages/cli/src/modules/config/lib/config.ts |  8 +++--
 .../commands/package/start/startFrontend.ts   |  2 +-
 .../src/modules/start/commands/repo/start.ts  | 36 ++++++++++++++++---
 4 files changed, 40 insertions(+), 7 deletions(-)

diff --git a/packages/cli/src/modules/build/lib/bundler/server.ts b/packages/cli/src/modules/build/lib/bundler/server.ts
index 4541ecf12c..9d4af5c0fe 100644
--- a/packages/cli/src/modules/build/lib/bundler/server.ts
+++ b/packages/cli/src/modules/build/lib/bundler/server.ts
@@ -77,6 +77,7 @@ DEPRECATION WARNING: React Router Beta is deprecated and support for it will be
 
   const cliConfig = await loadCliConfig({
     args: options.configPaths,
+    targetDir: options.targetDir,
     fromPackage: name,
     withFilteredKeys: true,
     watch(appConfigs) {
diff --git a/packages/cli/src/modules/config/lib/config.ts b/packages/cli/src/modules/config/lib/config.ts
index afed53af6f..a8d137c60a 100644
--- a/packages/cli/src/modules/config/lib/config.ts
+++ b/packages/cli/src/modules/config/lib/config.ts
@@ -19,9 +19,11 @@ import { AppConfig, ConfigReader } from '@backstage/config';
 import { paths } from '../../../lib/paths';
 import { getPackages } from '@manypkg/get-packages';
 import { PackageGraph } from '@backstage/cli-node';
+import { resolve as resolvePath } from 'path';
 
 type Options = {
   args: string[];
+  targetDir?: string;
   fromPackage?: string;
   mockEnv?: boolean;
   withFilteredKeys?: boolean;
@@ -32,8 +34,10 @@ type Options = {
 };
 
 export async function loadCliConfig(options: Options) {
+  const targetDir = options.targetDir ?? paths.targetDir;
+
   // Consider all packages in the monorepo when loading in config
-  const { packages } = await getPackages(paths.targetDir);
+  const { packages } = await getPackages(targetDir);
 
   let localPackageNames;
   if (options.fromPackage) {
@@ -70,7 +74,7 @@ export async function loadCliConfig(options: Options) {
       : undefined,
     watch: Boolean(options.watch),
     rootDir: paths.targetRoot,
-    argv: options.args.flatMap(t => ['--config', paths.resolveTarget(t)]),
+    argv: options.args.flatMap(t => ['--config', resolvePath(targetDir, t)]),
   });
 
   const appConfigs = await new Promise<AppConfig[]>((resolve, reject) => {
diff --git a/packages/cli/src/modules/start/commands/package/start/startFrontend.ts b/packages/cli/src/modules/start/commands/package/start/startFrontend.ts
index 23aa46d7f7..d4b2f6a1cd 100644
--- a/packages/cli/src/modules/start/commands/package/start/startFrontend.ts
+++ b/packages/cli/src/modules/start/commands/package/start/startFrontend.ts
@@ -37,7 +37,7 @@ interface StartAppOptions {
 
 export async function startFrontend(options: StartAppOptions) {
   const packageJson = (await readJson(
-    paths.resolveTarget('package.json'),
+    resolvePath(options.targetDir ?? paths.targetDir, 'package.json'),
   )) as BackstagePackageJson;
 
   const waitForExit = await serveBundle({
diff --git a/packages/cli/src/modules/start/commands/repo/start.ts b/packages/cli/src/modules/start/commands/repo/start.ts
index ef51a8e89d..6ca204e169 100644
--- a/packages/cli/src/modules/start/commands/repo/start.ts
+++ b/packages/cli/src/modules/start/commands/repo/start.ts
@@ -23,6 +23,7 @@ import { relative as relativePath } from 'path';
 import { paths } from '../../../../lib/paths';
 import { resolveLinkedWorkspace } from '../package/start/resolveLinkedWorkspace';
 import { startPackage } from '../package/start/startPackage';
+import { parseArgs } from 'util';
 
 const ACCEPTED_PACKAGE_ROLES: Array<PackageRole | undefined> = [
   'frontend',
@@ -40,19 +41,46 @@ export async function command(
     `Starting ${targetPackages.map(p => p.packageJson.name).join(', ')}`,
   );
 
-  // Blocking
+  // Each of these block until interrupt by user
   await Promise.all(
     targetPackages.map(async pkg => {
-      const opts = { config: [], require: undefined };
+      const startScript = pkg.packageJson.scripts?.start;
+      if (!startScript) {
+        console.log(
+          `No start script found for package ${pkg.packageJson.name}, skipping...`,
+        );
+        return undefined;
+      }
+
+      // Grab and parse --config and --require options from the start scripts, the rest are ignored
+      // TODO(Rugvip): Prolly switch over to completely different arg parsing to avoid this duplication
+      const { values: parsedOpts } = parseArgs({
+        args: startScript.split(' '),
+        strict: false,
+        options: {
+          config: {
+            type: 'string',
+            multiple: true,
+          },
+          require: {
+            type: 'string',
+          },
+        },
+      });
+      const parsedRequire =
+        typeof parsedOpts.require === 'string' ? parsedOpts.require : undefined;
+      const parsedConfig =
+        parsedOpts.config?.filter(c => typeof c === 'string') ?? [];
+
       return startPackage({
         role: pkg.packageJson.backstage?.role!,
         targetDir: pkg.dir,
-        configPaths: opts.config as string[],
+        configPaths: options.config.length > 0 ? options.config : parsedConfig,
         checksEnabled: false,
         linkedWorkspace: await resolveLinkedWorkspace(options.link),
         inspectEnabled: false,
         inspectBrkEnabled: false,
-        require: opts.require,
+        require: parsedRequire,
       });
     }),
   );