/**
* Deno Availability Checker
*
* Checks if Deno is installed and available for TypeScript execution.
* Used to gracefully fallback to Python-only mode if Deno is not found.
*/
import { spawn } from 'child_process';
import { getDenoPath } from '../config/loader.js';
let denoAvailable: boolean | null = null;
let denoVersion: string | null = null;
/**
* Try to execute deno --version with a given path
*/
async function tryDenoPath(denoPath: string): Promise<{ success: boolean; version?: string }> {
return new Promise((resolve) => {
const proc = spawn(denoPath, ['--version'], {
stdio: ['ignore', 'pipe', 'pipe'],
});
let stdout = '';
proc.stdout.on('data', (data) => {
stdout += data.toString();
});
proc.on('close', (code) => {
if (code === 0 && stdout) {
// Parse version from output (e.g., "deno 2.0.0")
const match = stdout.match(/deno\s+(\d+\.\d+\.\d+)/i);
const version = match ? match[1] : 'unknown';
resolve({ success: true, version });
} else {
resolve({ success: false });
}
});
proc.on('error', () => {
resolve({ success: false });
});
// Timeout after 2 seconds
setTimeout(() => {
proc.kill();
resolve({ success: false });
}, 2000);
});
}
/**
* Check if Deno is installed and available
*
* Tries multiple common locations before giving up.
*
* @returns Promise<boolean> - True if Deno is available, false otherwise
*/
export async function checkDenoAvailable(): Promise<boolean> {
// Return cached result if already checked
if (denoAvailable !== null) {
return denoAvailable;
}
try {
const configuredPath = getDenoPath();
// Try paths in order of preference
const pathsToTry = [
configuredPath, // Configured path (from env var or config)
// Common installation locations
process.env.HOME ? `${process.env.HOME}/.deno/bin/deno` : null,
'/usr/local/bin/deno',
'/usr/bin/deno',
'/opt/homebrew/bin/deno',
'deno', // Finally try PATH
].filter((p): p is string => p !== null && p !== '');
// Remove duplicates
const uniquePaths = [...new Set(pathsToTry)];
// Try each path until one works
for (const path of uniquePaths) {
const result = await tryDenoPath(path);
if (result.success) {
denoAvailable = true;
denoVersion = result.version ?? null;
return true;
}
}
// None of the paths worked
denoAvailable = false;
return false;
} catch {
denoAvailable = false;
return false;
}
}
/**
* Get Deno version string
*
* @returns string | null - Deno version or null if not available
*/
export function getDenoVersion(): string | null {
return denoVersion;
}
/**
* Get a helpful error message when Deno is not available
*/
export function getDenoInstallMessage(): string {
return `
⚠️ Deno not found - TypeScript execution disabled
To enable TypeScript execution (executeTypescript tool):
1. Install Deno:
curl -fsSL https://deno.land/install.sh | sh
2. Or use Docker deployment (Deno included):
docker-compose up -d
Python execution (executePython tool) is still available.
For more info: https://deno.land/manual/getting_started/installation
`.trim();
}
