import { spawn } from 'child_process';
/**
* SelfInstaller - Detects and installs code-executor-mcp globally
*
* Implements FR-0 (Self-Installation Bootstrap) from spec.md.
* Wizard detects if package is globally installed and auto-installs if needed.
*
* @security
* - Uses npm official commands (no shell eval)
* - Inherits stdio for install progress visibility
* - Provides remediation messages for permission errors
*/
export class SelfInstaller {
private readonly packageName = 'code-executor-mcp';
/**
* Detects if code-executor-mcp is globally installed
*
* Uses `npm list -g` which is the official npm API for checking installations.
* Cross-platform compatible (Linux, macOS, Windows).
*
* @returns true if package is globally installed, false otherwise
*/
async detectGlobalInstall(): Promise<boolean> {
return new Promise((resolve) => {
try {
const npmProcess = spawn('npm', [
'list',
'-g',
this.packageName,
'--depth=0',
'--json'
]);
npmProcess.on('close', (code) => {
// Exit code 0 = installed, non-zero = not installed
resolve(code === 0);
});
npmProcess.on('error', (err) => {
// npm not found or other spawn error
console.warn(`npm detection failed: ${err.message}`);
resolve(false);
});
} catch (error) {
// Catch any unexpected errors
console.warn(`Unexpected error during detection: ${error}`);
resolve(false);
}
});
}
/**
* Installs code-executor-mcp globally
*
* Runs `npm install -g code-executor-mcp` with inherited stdio for user visibility.
* Handles permission errors (EACCES) with remediation message.
*
* @returns Promise resolving to { success: true } on success
* @throws Error with remediation message on permission denial or installation failure
*/
async installGlobally(): Promise<{ success: boolean }> {
return new Promise((resolve, reject) => {
// Only pipe stderr for error detection, inherit stdin/stdout for visibility
const npmProcess = spawn('npm', ['install', '-g', this.packageName], {
stdio: ['inherit', 'inherit', 'pipe']
});
let stderrOutput = '';
// Capture stderr for EACCES detection
npmProcess.stderr!.on('data', (data) => {
const chunk = data.toString();
stderrOutput += chunk;
// Also write to stderr so user sees errors in real-time
process.stderr.write(chunk);
});
npmProcess.on('close', (code) => {
if (code === 0) {
resolve({ success: true });
} else if (code === 243 || stderrOutput.includes('EACCES')) {
// Permission denied error
reject(new Error(
`Permission denied: Try running: sudo npm install -g ${this.packageName}
Or configure npm to use a user-writable directory: https://docs.npmjs.com/resolving-eacces-permissions-errors-when-installing-packages-globally`
));
} else {
reject(new Error(
`Installation failed with exit code ${code}. Check network connection and npm configuration.`
));
}
});
npmProcess.on('error', (err) => {
reject(new Error(`npm not found or failed to spawn: ${err.message}`));
});
});
}
/**
* Runs bootstrap flow: detect → install if needed
*
* This is the main entry point called by the setup wizard.
* Implements idempotent behavior (skips install if already present).
*
* @throws Error with remediation message if installation fails
*/
async runBootstrap(): Promise<void> {
console.log('🔍 Checking if code-executor-mcp is globally installed...');
const isInstalled = await this.detectGlobalInstall();
if (isInstalled) {
console.log('✅ code-executor-mcp is already globally installed. Skipping installation.');
return;
}
console.log('❌ code-executor-mcp is not globally installed.');
console.log('📦 Installing globally...');
try {
await this.installGlobally();
console.log('✅ Installation successful!');
} catch (error) {
console.error(`❌ Installation failed: ${error instanceof Error ? error.message : 'Unknown error'}`);
throw error;
}
}
}
