nodesync-cli/core/detectVersion.js

A smart CLI tool to auto-detect, install, and manage the right Node.js version for your project.

import fs from 'fs';
import path from 'path';

export async function detectVersion(projectRoot = process.cwd()) {
  // 1. Check .nvmrc
  const nvmrcPath = path.join(projectRoot, '.nvmrc');
  if (fs.existsSync(nvmrcPath)) {
    const version = fs.readFileSync(nvmrcPath, 'utf-8').trim();
    if (version) {
      return { source: '.nvmrc', version };
    }
  }

  // 2. Check package.json → engines.node
  const pkgJsonPath = path.join(projectRoot, 'package.json');
  if (fs.existsSync(pkgJsonPath)) {
    const pkg = JSON.parse(fs.readFileSync(pkgJsonPath, 'utf-8'));
    if (pkg.engines && pkg.engines.node) {
      return { source: 'package.json', version: pkg.engines.node };
    }
  }

  // 3. Check Dockerfile → FROM node:X.Y.Z
  const dockerfilePath = path.join(projectRoot, 'Dockerfile');
  if (fs.existsSync(dockerfilePath)) {
    const content = fs.readFileSync(dockerfilePath, 'utf-8');
    const match = content.match(/FROM\s+node:(\d+\.\d+\.\d+)/i);
    if (match) {
      return { source: 'Dockerfile', version: match[1] };
    }
  }

  // Nothing found
  return null;
}