@warren-bank/node-request-cli/bin/nget/process_argv/process_post_data.js

An extremely lightweight HTTP request client for the command-line. Supports: http, https, proxy, redirects, cookies, content-encoding, multipart/form-data, multi-threading, recursive website crawling and mirroring.

const fs = require('fs')

const regex = {
  b64encode: /\{\{btoa\s+(.*?)\s*\}\}/g,
  b64decode: /\{\{atob\s+(.*?)\s*\}\}/g,

  urlencode: /\{\{\+\s*(.*?)\s*\}\}/g,
  urldecode: /\{\{\-\s*(.*?)\s*\}\}/g,

  filepath:  /\{\{\@\s*(.*?)\s*\}\}/g,
  qs: /(?:^|&)([^=]+)=([^&]*)/g
}

const reset_global_regex = (r) => {
  if (r instanceof RegExp) {
    r.lastIndex = 0
  }
  return r
}

// Use a token to split filepath into 2x components: filepath and content-type.
// The default token is '|'.
//   ex: image.png | image/png
// In most cases, an explicit content-type is not necessary;
// it will be chosen based on the filename extension.
const split_filepath = (filepath, sep = '|') => {
  let filename, mime

  const pos = filepath.indexOf(sep)

  if (pos >= 0) {
    if (pos > 0) {
      filename = filepath.substring(0, pos).trim()
    }

    if ((pos + sep.length) < filepath.length) {
      mime = filepath.substring((pos + sep.length), filepath.length).trim()
    }
  }
  else {
    filename = filepath.trim()
  }

  return {filename, mime}
}

const process_post_data = (POST_data, content_type) => {
  if (!POST_data || !(typeof POST_data === 'string')) return null

  POST_data = POST_data.replace(reset_global_regex(regex.b64encode), (match, p1) => p1 ? btoa(p1) : '')
  POST_data = POST_data.replace(reset_global_regex(regex.b64decode), (match, p1) => p1 ? atob(p1) : '')

  POST_data = POST_data.replace(reset_global_regex(regex.urlencode), (match, p1) => p1 ? encodeURIComponent(p1) : '')
  POST_data = POST_data.replace(reset_global_regex(regex.urldecode), (match, p1) => p1 ? decodeURIComponent(p1) : '')

  const placeholder = '{{xXx---stream---Readable---xXx}}'
  const files = []

  POST_data = POST_data.replace(reset_global_regex(regex.filepath), (match, p1) => {
    let details

    if (!p1) return ''

    if (p1[0] === '-') {
      details = {file: process.stdin}

      if (p1.length > 1) {
        p1 = p1.substring(1, p1.length)

        Object.assign(details, split_filepath(p1))
      }

      files.push(details)
      return placeholder
    }
    else {
      details = split_filepath(p1)

      try {
        if (!details.filename) throw ''

        details.filename = fs.realpathSync(details.filename)
      }
      catch(e) {
        // file path does not exist
        return ''
      }

      files.push(details)
      return placeholder
    }
  })

  const require_multipart_form_data = (content_type && (typeof content_type === 'string') && (content_type.toLowerCase().indexOf('multipart/form-data') >= 0))

  if (!files.length && !require_multipart_form_data)
    return POST_data

  // multipart/form-data
  const fields = []
  let matches, field_name, field_value

  reset_global_regex(regex.qs)
  while (matches = regex.qs.exec(POST_data)) {
    field_name  = matches[1]
    field_value = matches[2]

    if (!field_value) continue

    field_name  = decodeURIComponent(field_name)
    field_name  = encodeURIComponent(field_name)

    field_value = decodeURIComponent(field_value)

    if (field_value === placeholder)
      field_value = files.shift()

    fields.push({name: field_name, value: field_value})
  }

  return fields.length
    ? fields
    : null
}

module.exports = process_post_data