WebP Batch Converter

import { spawn } from 'child_process'; import { promises as fs } from 'fs'; import { join, extname, dirname, basename } from 'path'; import sharp from 'sharp'; import { glob } from 'glob'; import pLimit from 'p-limit'; import chalk from 'chalk'; export interface ConvertOptions { src: string; quality: number; lossless: boolean; overwrite: boolean; threads: number; preserveMeta: boolean; flat?: string; } export interface ConvertResult { converted: string[]; skipped: string[]; errors: Array<{ file: string; error: string }>; originalKB: number; webpKB: number; savings: number; } export class WebPConverter { private cwebpAvailable: boolean | null = null; async checkCWebP(): Promise<boolean> { if (this.cwebpAvailable !== null) return this.cwebpAvailable; try { await new Promise((resolve, reject) => { const child = spawn('cwebp', ['-version'], { stdio: 'pipe' }); child.on('error', reject); child.on('close', (code) => code === 0 ? resolve(void 0) : reject()); }); this.cwebpAvailable = true; console.log(chalk.green('✓ Using cwebp (Google WebP tools)')); } catch { this.cwebpAvailable = false; console.log(chalk.yellow('⚠ cwebp not found, falling back to sharp')); } return this.cwebpAvailable; } async findImages(srcDir: string): Promise<string[]> { const patterns = ['**/*.{png,jpg,jpeg,PNG,JPG,JPEG}']; const files = await glob(patterns, { cwd: srcDir, absolute: true }); return files; } async convertWithCWebP(inputPath: string, outputPath: string, options: ConvertOptions): Promise<void> { const args = [inputPath, '-o', outputPath]; if (options.lossless) { args.push('-lossless'); } else { args.push('-q', options.quality.toString()); } if (options.preserveMeta) { args.push('-metadata', 'exif,icc'); } await new Promise<void>((resolve, reject) => { const child = spawn('cwebp', args, { stdio: 'pipe' }); child.on('error', reject); child.on('close', (code) => { if (code === 0) resolve(); else reject(new Error(`cwebp exit code: ${code}`)); }); }); } async convertWithSharp(inputPath: string, outputPath: string, options: ConvertOptions): Promise<void> { let sharpInstance = sharp(inputPath); if (options.preserveMeta) { sharpInstance = sharpInstance.withMetadata(); } const webpOptions: sharp.WebpOptions = { quality: options.lossless ? undefined : options.quality, lossless: options.lossless }; await sharpInstance.webp(webpOptions).toFile(outputPath); } async convertSingle(inputPath: string, options: ConvertOptions): Promise<{ success: boolean; error?: string; originalSize: number; webpSize: number }> { try { const inputStat = await fs.stat(inputPath); const originalSize = inputStat.size; let outputPath: string; if (options.flat) { await fs.mkdir(options.flat, { recursive: true }); const filename = basename(inputPath, extname(inputPath)) + '.webp'; outputPath = join(options.flat, filename); } else if (options.overwrite) { outputPath = inputPath.replace(/\.(png|jpe?g)$/i, '.webp'); } else { const dir = dirname(inputPath); const name = basename(inputPath, extname(inputPath)); outputPath = join(dir, `${name}.webp`); } const canUseCWebP = await this.checkCWebP(); if (canUseCWebP) { await this.convertWithCWebP(inputPath, outputPath, options); } else { await this.convertWithSharp(inputPath, outputPath, options); } // Clean up original if overwrite is true and we're not already a webp if (options.overwrite && !inputPath.toLowerCase().endsWith('.webp')) { await fs.unlink(inputPath); } const webpStat = await fs.stat(outputPath); const webpSize = webpStat.size; return { success: true, originalSize, webpSize }; } catch (error) { return { success: false, error: error instanceof Error ? error.message : String(error), originalSize: 0, webpSize: 0 }; } } async batchConvert(options: ConvertOptions): Promise<ConvertResult> { console.log(chalk.blue(`🔍 Scanning ${options.src} for images...`)); const images = await this.findImages(options.src); const limit = pLimit(options.threads); console.log(chalk.blue(`📁 Found ${images.length} images`)); console.log(chalk.blue(`🚀 Converting with ${options.threads} threads...`)); const result: ConvertResult = { converted: [], skipped: [], errors: [], originalKB: 0, webpKB: 0, savings: 0 }; const tasks = images.map(imagePath => limit(async () => { const convertResult = await this.convertSingle(imagePath, options); if (convertResult.success) { result.converted.push(imagePath); result.originalKB += convertResult.originalSize / 1024; result.webpKB += convertResult.webpSize / 1024; console.log(chalk.green(`✓ ${basename(imagePath)}`)); } else { result.errors.push({ file: imagePath, error: convertResult.error || 'Unknown error' }); console.log(chalk.red(`✗ ${basename(imagePath)}: ${convertResult.error}`)); } }) ); await Promise.all(tasks); result.savings = result.originalKB > 0 ? Math.round(((result.originalKB - result.webpKB) / result.originalKB) * 100) : 0; return result; } }