audiobookshelf/server/utils/zipHelpers.js

const Logger = require('../Logger')
const archiver = require('../libs/archiver')

module.exports.zipDirectoryPipe = (path, filename, res) => {
  return new Promise((resolve, reject) => {
    // create a file to stream archive data to
    res.attachment(filename)

    const archive = archiver('zip', {
      zlib: { level: 9 } // Sets the compression level.
    })

    // listen for all archive data to be written
    // 'close' event is fired only when a file descriptor is involved
    res.on('close', () => {
      Logger.info(archive.pointer() + ' total bytes')
      Logger.debug('archiver has been finalized and the output file descriptor has closed.')
      resolve()
    })

    // This event is fired when the data source is drained no matter what was the data source.
    // It is not part of this library but rather from the NodeJS Stream API.
    // @see: https://nodejs.org/api/stream.html#stream_event_end
    res.on('end', () => {
      Logger.debug('Data has been drained')
    })

    // good practice to catch warnings (ie stat failures and other non-blocking errors)
    archive.on('warning', function (err) {
      if (err.code === 'ENOENT') {
        // log warning
        Logger.warn(`[DownloadManager] Archiver warning: ${err.message}`)
      } else {
        // throw error
        Logger.error(`[DownloadManager] Archiver error: ${err.message}`)
        // throw err
        reject(err)
      }
    })
    archive.on('error', function (err) {
      Logger.error(`[DownloadManager] Archiver error: ${err.message}`)
      reject(err)
    })

    // pipe archive data to the file
    archive.pipe(res)

    archive.directory(path, false)

    archive.finalize()
  })
}