btrtracks/src/server.js

import path from 'path'
import sqlite from 'sqlite'
import Promise from 'bluebird'
import express from 'express'
import http from 'http'
import https from 'https'
import ffmpeg from 'fluent-ffmpeg'

import lfmda from './lastfm'

require('express-async-errors')

const values = require(path.join(process.cwd(), 'values.json'))
const tracksPerPage = 100

const dbPromise = Promise.resolve()
  .then(() => sqlite.open(path.join(process.cwd(), values.database), { Promise, cache: true }))
  .then(db => db.migrate())

const app = express()
const port = process.env.PORT || 3000

const dev = process.env.NODE_ENV === 'development'
const server = http.createServer(app)

const lastfm = lfmda(dbPromise)

if (dev) {
  const morgan = require('morgan')
  app.use(morgan('dev'))
}

const router = express.Router()

const sortfields = ['id', 'track', 'artist', 'title', 'album', 'year', 'file']
const srchcategories = ['title', 'artist', 'album']

router.get('/tracks', async (req, res) => {
  let page = parseInt(req.query.page) || 1
  if (isNaN(page)) {
    page = 1
  }

  let sort = req.query.sort
  if (!sort || sortfields.indexOf(sort.toLowerCase()) === -1) {
    sort = 'artist'
  }

  let sortdir = req.query.sortdir
  if (!sortdir || (sortdir !== 'desc' && sortdir !== 'asc')) {
    sortdir = 'asc'
  }

  let db = await dbPromise
  let count = (await db.get('SELECT COUNT(*) FROM Track'))['COUNT(*)']

  let pageCount = Math.ceil(count / tracksPerPage)

  if (page > pageCount) page = pageCount

  let offset = (page - 1) * tracksPerPage
  let tracks = await db.all(`SELECT * FROM Track ORDER BY ${sort} ${sortdir.toUpperCase()} LIMIT ? OFFSET ?`, tracksPerPage, offset)

  for (let i in tracks) {
    delete tracks[i].file
  }

  res.jsonp({
    page, count, pageCount, tracks
  })
})

router.get('/tracks/search', async (req, res) => {
  let query = req.query.q
  let streamable = (req.query.streamable === '1')
  let qr = ''
  let exact = false

  if (query.indexOf(':') !== -1) {
    let ctr = query.split(':')

    if (srchcategories.indexOf(ctr[0]) !== -1) {
      qr = `ifnull(${ctr[0]}, '')`
      query = query.substring(ctr[0].length + 1)
    }
  }

  if (qr === '') {
    for (let c in srchcategories) {
      let cat = srchcategories[c]
      if (parseInt(c) !== 0) qr += ' || '
      qr += `ifnull(${cat}, '')`
    }
  }

  if (query.indexOf('=') !== -1 && query.indexOf('\\=') === -1) {
    query = query.replace('=', '')
    exact = true
  }

  let original = String(query)
  if (!exact) query = `%${query}%`

  let sort = req.query.sort
  if (!sort || sortfields.indexOf(sort.toLowerCase()) === -1) {
    sort = 'artist'
  }

  let sortdir = req.query.sortdir
  if (!sortdir || (sortdir !== 'desc' && sortdir !== 'asc')) {
    sortdir = 'asc'
  }

  // Paging
  let page = parseInt(req.query.page) || 1
  if (isNaN(page)) {
    page = 1
  }

  let db = await dbPromise
  let count = (await db.get(`SELECT COUNT(*) FROM Track WHERE ${qr} LIKE ?`, query))['COUNT(*)']
  let pageCount = Math.ceil(count / tracksPerPage)

  if (page > pageCount) page = pageCount

  let offset = (page - 1) * tracksPerPage
  let tracks = await db.all(`SELECT * FROM Track WHERE ${qr} LIKE ? ORDER BY ${sort} ${sortdir.toUpperCase()} LIMIT ? OFFSET ?`,
    query, tracksPerPage, offset)

  let llimit = tracksPerPage - count
  if (streamable && page === pageCount && llimit > 1) {
    if (llimit < 10) llimit = 10
    try {
      let lfm = await lastfm.search(original, llimit)
      if (lfm && lfm.length) {
        tracks = tracks.concat(lfm)
        count = count + lfm.length
        if (page == 0) page = 1
        if (pageCount == 0) pageCount = 1
      }
    } catch (e) {}
  }

  for (let i in tracks) {
    delete tracks[i].file
  }

  res.jsonp({
    page, count, pageCount, tracks
  })
})

router.get('/track/:id', async (req, res, next) => {
  let id = req.params.id

  let db = await dbPromise
  let track = await db.get('SELECT * FROM Track WHERE id = ?', id)
  if (!track) {
    track = await lastfm.getTrackMetaReal(id)
    if (!track) return next(new Error('404 file not found'))
  }

  delete track.file

  res.jsonp(track)
})

router.get('/playlists', async (req, res, next) => {
  let db = await dbPromise
  let playlists = await db.all('SELECT * FROM Playlist')

  res.jsonp(playlists)
})

router.get('/playlist/:id', async (req, res, next) => {
  let id = req.params.id
  let db = await dbPromise
  let playlist = await db.get('SELECT title FROM Playlist WHERE id = ?', id)

  if (!playlist) return next(new Error('404 file not found'))

  let tracks = await db.all('SELECT trackId FROM PlaylistEntry WHERE playlistId = ?', id)
  playlist.tracks = tracks

  res.jsonp(playlist)
})

router.get('/serve/by-id/:id', async (req, res, next) => {
  let id = req.params.id
  let dl = (req.query.dl === '1')
  let db = await dbPromise
  let track = await db.get('SELECT file FROM Track WHERE id = ?', id)
  if (!track) {
    track = await lastfm.getTrackMetaReal(id)
    if (!track) return next(new Error('404 file not found'))
    if (dl) {
      lastfm.invokeDownload(id)
      return res.end('<p>OK</p><script>window.close();</script>')
    }
    return ffmpeg(track.file)
      .audioCodec('libmp3lame')
      .format('mp3')
      .on('error', (e) => console.error(e))
      .pipe(res, {end: true})
  }

  let fpath = path.resolve(track.file)

  res.set('Cache-Control', 'public, max-age=31557600')
  if (dl) return res.download(fpath)

  res.redirect('/file/track' + fpath.substring(values.directory.length))
})

router.use((err, req, res, next) => {
  console.error(err)
  res.status(404).jsonp({error: 404})
})

app.use('/api', router)
app.use('/file/track', express.static(path.resolve(values.directory)))
app.use('/', express.static(path.join(process.cwd(), 'public')))

const host = process.env.NODE_ENV === 'development' ? '0.0.0.0' : '127.0.0.1'

server.listen(port, host, function () {
  console.log(`app running on port ${port}`)
})