@zkochan/pnpm/lib/node_modules/dint/index.js

Fast, disk space efficient package manager

'use strict'

const fs = require('mz/fs')
const ssri = require('ssri')
const path = require('path')
const pEvery = require('p-every')
const pLimit = require('p-limit')

const limit = pLimit(20)

const MAX_BULK_SIZE = 1 * 1024 * 1024 // 1MB

function generateFrom (dirname) {
  return _retrieveFileIntegrities(dirname, dirname, {})
}

function _retrieveFileIntegrities (rootDir, currDir, index) {
  return fs.readdir(currDir)
  .then((files) => {
    return Promise.all(files.map((file) => {
      const fullPath = path.join(currDir, file)
      return fs.stat(fullPath)
      .then((stat) => {
        if (stat.isDirectory()) {
          return _retrieveFileIntegrities(rootDir, fullPath, index)
        }
        if (stat.isFile()) {
          const relativePath = path.relative(rootDir, fullPath)
          index[relativePath] = {
            size: stat.size,
            generatingIntegrity: limit(() => {
              return stat.size < MAX_BULK_SIZE
                     ? fs.readFile(fullPath).then(ssri.fromData)
                     : ssri.fromStream(fs.createReadStream(fullPath))
            })
          }
        }
      })
    }))
  })
  .then(() => index)
  .catch(err => {
    if (err.code !== 'ENOENT') {
      throw err
    }
    return index
  })
}

function check (dirname, dirIntegrity) {
  dirname = path.resolve(dirname)
  return pEvery(Object.keys(dirIntegrity), f => {
    const fstat = dirIntegrity[f]

    // TODO: return something else to distinguish an integrity mismatch from
    // a missing integrity
    if (!fstat.integrity) return false

    const filename = path.join(dirname, f)
    if (fstat.size > MAX_BULK_SIZE) {
      return ssri.checkStream(fs.createReadStream(filename), fstat.integrity)
        .catch(err => {
          if (err.code === 'EINTEGRITY' || err.code === 'ENOENT') return false
          throw err
        })
    }

    return fs.readFile(filename)
      .then(data => ssri.checkData(data, fstat.integrity))
      .catch(err => {
        if (err.code === 'EINTEGRITY' || err.code === 'ENOENT') return false
        throw err
      })
  }, {concurrency: 100})
}

module.exports = {
  from: generateFrom,
  check,
}