@tremorvideo/blink-cli/src/snippets/replace-blink-snippets.js

const fs = require('fs-extra')
const path = require('path')
const { promisify } = require('util')
const xml2js = require('xml2js')
const parseXML = promisify(xml2js.parseString)
const buildXML = new xml2js.Builder({ cdata: true })
const fsOpts = { encoding: 'utf8' }
const snippetsFileName = 'CodeSnippets.xml'

/**
 * This function is also used in the blink-snippets project gulpfile task updateXml.
 * When called from the gulpfile, the Blink XML has a placeholder for the version number.
 * If the parameter newVersion is set, it will be used to update the placeholder.
 *
 * @param {string} downloadPath
 * @param {string} destPath
 * @param {boolean} removeDownload
 * @param {string=} newVersion
 * @returns {Promise<void>}
 */
module.exports = async ({ downloadPath, destPath, removeDownload, newVersion }) => {
  removeDownload = !!removeDownload
  const downloadFile = path.join(downloadPath, snippetsFileName)
  const destFile = path.join(destPath, snippetsFileName)
  const newXmlObject = await readXml({ xmlFile: downloadFile })
  const blinkSnippets = filterBlinkSnippets({ xmlObject: newXmlObject, filterOut: false })
  const xmlObject = await readXml({ xmlFile: destFile })
  removeDownload && await fs.remove(downloadPath)
  const nonBlinkSnippets = filterBlinkSnippets({ xmlObject, filterOut: true })
  const mergedCategories = nonBlinkSnippets.concat(blinkSnippets)
  xmlObject.CodeSnippets.snippets[0].category = mergedCategories
  await writeXml({ xmlObject, xmlFileName: destFile, newVersion })
}

const readXml = async ({ xmlFile }) => {
  let xmlObject = null
  try {
    const xmlText = await fs.readFile(xmlFile, fsOpts)
    xmlObject = await parseXML(xmlText)
  } catch (err) {
    console.log('Error parsing existing CodeSnippets.xml')
    return Promise.reject(err)
  }
  return xmlObject
}

const filterBlinkSnippets = ({ xmlObject, filterOut }) => {
  filterOut = !!filterOut
  let categories = []
  let re
  if (filterOut) {
    re = /^(?!Blink Snippets).*/
  } else {
    re = /^Blink Snippets/
  }
  categories = xmlObject.CodeSnippets.snippets[0].category
    .filter((category) => {
      /*
       * Check that category is valid object before testing regular expression
       * (An invalid category will be an empty string)
       */
      if (typeof category !== 'object') return false
      return !category.$ || !category.$.title || re.test(category.$.title)
    })
  return categories
}

const writeXml = async ({ xmlObject, xmlFileName, newVersion }) => {
  let newXml = buildXML.buildObject(xmlObject)
  // Animate CC requires an empty comment string after the <CodeSnippets> tag
  const searchString = '<CodeSnippets>'
  const commentString = '\n<!-- -->'
  newXml = newXml.replace(searchString, searchString + commentString)
  if (newVersion) {
    newXml = newXml.replace(/BLINK_SNIPPETS_VERSION/, `${newVersion}`)
  }
  return fs.writeFile(xmlFileName, newXml, fsOpts)
}