Add dependency checks with helpful error messages

packages/atxp/src/check-dependencies.test.ts

@@ -0,0 +1,30 @@
+import { describe, it, expect } from 'vitest';
+import { checkDependency } from './check-dependencies.js';
+
+describe('checkDependency', () => {
+  it('should return true for available commands', async () => {
+    const nodeDependency = {
+      name: 'Node.js',
+      command: 'node',
+      args: ['--version'],
+      requiredFor: ['demo'],
+      installInstructions: 'Please install Node.js'
+    };
+
+    const result = await checkDependency(nodeDependency);
+    expect(result).toBe(true);
+  });
+
+  it('should return false for unavailable commands', async () => {
+    const fakeDependency = {
+      name: 'Fake Command',
+      command: 'nonexistent-command-12345',
+      args: ['--version'],
+      requiredFor: ['demo'],
+      installInstructions: 'This command does not exist'
+    };
+
+    const result = await checkDependency(fakeDependency);
+    expect(result).toBe(false);
+  });
+});

packages/atxp/src/check-dependencies.ts

@@ -0,0 +1,75 @@
+import { spawn } from 'child_process';
+import chalk from 'chalk';
+
+interface DependencyCheck {
+  name: string;
+  command: string;
+  args: string[];
+  requiredFor: string[];
+  installInstructions: string;
+}
+
+const DEPENDENCIES: DependencyCheck[] = [
+  {
+    name: 'Git',
+    command: 'git',
+    args: ['--version'],
+    requiredFor: ['demo', 'create'],
+    installInstructions: 'Please install Git from https://git-scm.com/downloads'
+  },
+  {
+    name: 'npm',
+    command: 'npm',
+    args: ['--version'],
+    requiredFor: ['demo'],
+    installInstructions: 'Please install Node.js (which includes npm) from https://nodejs.org/'
+  }
+];
+
+export async function checkDependency(dependency: DependencyCheck): Promise<boolean> {
+  return new Promise((resolve) => {
+    const process = spawn(dependency.command, dependency.args, {
+      stdio: 'ignore'
+    });
+
+    process.on('close', (code) => {
+      resolve(code === 0);
+    });
+
+    process.on('error', () => {
+      resolve(false);
+    });
+  });
+}
+
+export async function checkAllDependencies(command?: string): Promise<boolean> {
+  let allDependenciesOk = true;
+
+  for (const dependency of DEPENDENCIES) {
+    // If a specific command is provided, only check dependencies for that command
+    if (command && !dependency.requiredFor.includes(command)) {
+      continue;
+    }
+
+    const isAvailable = await checkDependency(dependency);
+
+    if (!isAvailable) {
+      console.error(chalk.red(`✗ ${dependency.name} is not installed or not available in PATH`));
+      console.error(chalk.yellow(`  Required for: ${dependency.requiredFor.join(', ')}`));
+      console.error(chalk.white(`  ${dependency.installInstructions}`));
+      console.error('');
+      allDependenciesOk = false;
+    }
+  }
+
+  return allDependenciesOk;
+}
+
+export function showDependencyError(command: string): void {
+  console.error(chalk.red(`Cannot run "${command}" command due to missing dependencies.`));
+  console.error(chalk.yellow('Please install the required dependencies and try again.'));
+  console.error('');
+  console.error(chalk.white('For help with installation, visit:'));
+  console.error(chalk.blue('  Git: https://git-scm.com/downloads'));
+  console.error(chalk.blue('  Node.js/npm: https://nodejs.org/'));
+}

packages/atxp/src/index.ts

@@ -5,6 +5,7 @@ import os from 'os';
 import { createProject } from './create-project.js';
 import { runDemo } from './run-demo.js';
 import { showHelp } from './help.js';
+import { checkAllDependencies, showDependencyError } from './check-dependencies.js';
 
 interface DemoOptions {
   port: number;
@@ -54,20 +55,37 @@ const isCreateMode = process.env.npm_config_argv?.includes('create') ||
                      command === 'create';
 
 // Handle different commands
-if (isCreateMode) {
-  console.log('Creating new ATXP project...');
-  createProject();
-} else if (command === 'demo') {
-  console.log('Starting ATXP demo...');
-  runDemo(demoOptions);
-} else if (command === 'help' || command === '--help' || command === '-h') {
-  showHelp();
-} else if (!command) {
-  // No command provided - show help instead of running demo
-  showHelp();
-} else {
-  // Unknown command
-  console.log(`Unknown command: ${command}`);
-  console.log('Run "npx atxp help" for usage information.');
+async function main() {
+  if (isCreateMode) {
+    console.log('Creating new ATXP project...');
+    const dependenciesOk = await checkAllDependencies('create');
+    if (!dependenciesOk) {
+      showDependencyError('create');
+      process.exit(1);
+    }
+    createProject();
+  } else if (command === 'demo') {
+    console.log('Starting ATXP demo...');
+    const dependenciesOk = await checkAllDependencies('demo');
+    if (!dependenciesOk) {
+      showDependencyError('demo');
+      process.exit(1);
+    }
+    runDemo(demoOptions);
+  } else if (command === 'help' || command === '--help' || command === '-h') {
+    showHelp();
+  } else if (!command) {
+    // No command provided - show help instead of running demo
+    showHelp();
+  } else {
+    // Unknown command
+    console.log(`Unknown command: ${command}`);
+    console.log('Run "npx atxp help" for usage information.');
+    process.exit(1);
+  }
+}
+
+main().catch((error) => {
+  console.error('An unexpected error occurred:', error.message);
   process.exit(1);
-}
+});

packages/atxp/src/run-demo.ts

@@ -1,7 +1,6 @@
 import chalk from 'chalk';
 import { spawn } from 'child_process';
 import fs from 'fs-extra';
-import path from 'path';
 import open from 'open';
 
 interface DemoOptions {