xml streams sax

sax-stream.js

const sax = require('sax')
const strict = false
const duplex = require('duplexer2')
const stream = require('stream')

module.exports = (itemPath) => {
  const parser = sax.parser(strict, { lowercase: true, trim: true, normalize: true })
  const readable = new stream.Readable({ objectMode: true })
  const writable = new stream.Writable({ objectMode: true })

  readable._read = (f) => f

  let root = ''
  let item
  let tag

  parser.ontext = (text) => {
    const value = text.trim()
    if (item) {
      if (!item[tag]) item[tag] = ''
      item[tag] += value
      if (tag === 'category') {
        console.log('text', text)
        console.log('value', value)
        console.log('item[tag]', item[tag])
      }
    }
  }

  parser.onopentag = (node) => {
    if (root) root += '.'
    root += node.name
    if (root === itemPath) {
      item = {}
    } else {
      tag = node.name
    }
  }

  parser.onclosetag = (node) => {
    if (root === itemPath) {
      if (item && Object.keys(item).length) readable.push(item)
    }
    root = root.split('.').slice(0, -1).join('.')
  }

  parser.onerror = (err) => {
    reader.emit('error', err)
  })

  writable._write = (chunk, encoding, cb) => {
    console.log('ENCODING', encoding)
    parser.write(chunk)
    cb()
  }

  writable.once('finish', () => readable.push(null))

  return duplex({ objectMode: true }, writable, readable)
}