unpkg/server/middleware/utils/getMetadata.js

const fs = require('fs')
const path = require('path')
const SRIToolbox = require('sri-toolbox')
const getFileContentType = require('./getFileContentType')
const getFileStats = require('./getFileStats')
const getFileType = require('./getFileType')

function getEntries(dir, file, maximumDepth) {
  return new Promise(function(resolve, reject) {
    fs.readdir(path.join(dir, file), function(error, files) {
      if (error) {
        reject(error)
      } else {
        resolve(
          Promise.all(
            files.map(function(f) {
              return getFileStats(path.join(dir, file, f))
            })
          ).then(function(statsArray) {
            return Promise.all(
              statsArray.map(function(stats, index) {
                return getMetadataRecursive(
                  dir,
                  path.join(file, files[index]),
                  stats,
                  maximumDepth - 1
                )
              })
            )
          })
        )
      }
    })
  })
}

function formatTime(time) {
  return new Date(time).toISOString()
}

function getIntegrity(file) {
  return new Promise(function(resolve, reject) {
    fs.readFile(file, function(error, data) {
      if (error) {
        reject(error)
      } else {
        resolve(SRIToolbox.generate({ algorithms: ['sha384'] }, data))
      }
    })
  })
}

function getMetadataRecursive(dir, file, stats, maximumDepth) {
  const metadata = {
    lastModified: formatTime(stats.mtime),
    contentType: getFileContentType(file),
    path: file,
    size: stats.size,
    type: getFileType(stats)
  }

  if (stats.isFile()) {
    return getIntegrity(path.join(dir, file)).then(function(integrity) {
      metadata.integrity = integrity
      return metadata
    })
  }

  if (!stats.isDirectory() || maximumDepth === 0)
    return Promise.resolve(metadata)

  return getEntries(dir, file, maximumDepth).then(function(files) {
    metadata.files = files
    return metadata
  })
}

function getMetadata(baseDir, path, stats, maximumDepth, callback) {
  getMetadataRecursive(baseDir, path, stats, maximumDepth).then(function(
    metadata
  ) {
    callback(null, metadata)
  },
  callback)
}

module.exports = getMetadata