sharpPlugin.ts

import { extname } from 'node:path'
import sharp, { FormatEnum } from 'sharp'
import type { Plugin } from 'vite'

function sharpPlugin(): Plugin {
  return {
    name: 'vite:sharp',
    enforce: 'post',
    apply: 'build',
    async generateBundle(_, bundle) {
      for (const asset of Object.values(bundle)) {
        if (asset.type == 'chunk') continue
        if (!/\.(jpe?g|png)$/i.test(asset.name!)) continue
        const source = asset.source as Buffer
        const ext = extname(asset.name!).slice(1).toLowerCase()
        const result = await sharp(source)
          .toFormat(ext as keyof FormatEnum)
          .toBuffer()
        if (result.byteLength >= source.byteLength) continue
        asset.source = result
      }
    }
  }
}

export default sharpPlugin