prisme-flow/nodes/bridge/bot/bot-document.js

prisme platform flow engine

/**
 * Created by prisme.io on 09/06/2017.
 */

var _ = require('underscore')
var fs = require('fs')
var Path = require('path')
var utils = require('./lib/helpers/utils')
var sanitize = require('sanitize-filename')
var mime = require('mime')
var BufferTransformers = require('./lib/buffer-transformers')

var ValidExtensions = {
  'facebook': ['.pdf', '.png', '.jpg', '.zip', '.gif'],
  'telegram': ['.pdf', '.gif', '.zip']
}

module.exports = function (RED) {
  function BotDocument (config) {
    RED.nodes.createNode(this, config)
    var node = this
    this.filename = config.filename
    this.name = config.name
    this.caption = config.caption
    this.transports = ['telegram', 'facebook']

    this.on('input', function (msg) {
      // var path = node.filename;
      var name = node.name
      var chatId = utils.getChatId(msg)
      var messageId = utils.getMessageId(msg)
      var transport = utils.getTransport(msg)
      var validExtensions = ValidExtensions[transport]
      var file = null

      // check transport compatibility
      if (!utils.matchTransport(node, msg)) {
        return
      }

      var defaultFilename = null
      if (!_.isEmpty(msg.filename)) {
        defaultFilename = msg.filename
      } else if (!_.isEmpty(name)) {
        defaultFilename = sanitize(name)
      } else if (msg.payload != null && !_.isEmpty(msg.payload.filename)) {
        defaultFilename = msg.payload.filename
      } else if (msg.payload != null && !_.isEmpty(msg.filename)) {
        defaultFilename = msg.filename
      }

      var path = null
      if (!_.isEmpty(node.filename)) {
        path = node.filename
      } else if (!_.isEmpty(msg.filename)) {
        path = msg.filename
      }

      if (!_.isEmpty(path)) {
        if (!fs.existsSync(path)) {
          node.error('File doesn\'t exist: ' + path)
          return
        }
        file = {
          filename: Path.basename(path),
          buffer: fs.readFileSync(path),
          mimeType: mime.lookup(path),
          extension: Path.extname(path)
        }
      } else if (msg.payload instanceof Buffer) {
        // handle a file buffer passed through payload
        if (_.isEmpty(defaultFilename) || _.isEmpty(Path.extname(defaultFilename))) {
          node.error('Unknown file type, use the "name" parameter to specify the file name and extension as default')
          return
        }
        file = {
          filename: Path.basename(defaultFilename),
          extension: Path.extname(defaultFilename),
          mimeType: mime.lookup(defaultFilename),
          buffer: msg.payload
        }
      } else if (_.isObject(msg.payload) && msg.payload.file instanceof Buffer) {
        // handle a buffer passed by another document node
        if (_.isEmpty(defaultFilename) || _.isEmpty(Path.extname(defaultFilename))) {
          node.error('Unknown file type, use the "name" parameter to specify the file name and extension as default')
          return
        }
        file = {
          filename: Path.basename(defaultFilename),
          extension: Path.extname(defaultFilename),
          mimeType: mime.lookup(defaultFilename),
          buffer: msg.payload.file
        }
      }
      // exit if no file description
      if (file == null) {
        return
      }
      // get caption
      var caption = null
      if (!_.isEmpty(node.caption)) {
        caption = node.caption
      } else if (_.isObject(msg.payload) && _.isString(msg.payload.caption) && !_.isEmpty(msg.payload.caption)) {
        caption = msg.payload.caption
      }
      // if the file has a not accepted extension, then zip it
      var transform = BufferTransformers.identity
      if (!_(validExtensions).contains(file.extension)) {
        transform = BufferTransformers.zip
      }
      // zip the file if needed or leave it as is
      transform(file)
        .then(function (newFile) {
          // console.log('++++', newFile);
          // send out the message
          msg.payload = {
            type: 'document',
            content: newFile.buffer,
            filename: newFile.filename,
            caption: caption,
            chatId: chatId,
            messageId: messageId,
            inbound: false,
            mimeType: newFile.mimeType
          }
          // send out reply
          node.send(msg)
        })
    })
  }

  RED.nodes.registerType('bot-document', BotDocument)
}