vue-cli/packages/@vue/cli-ui/apollo-server/connectors/client-addons.js

const path = require('path')
// Subs
const channels = require('../channels')
// Utils
const { resolveModuleRoot } = require('../util/resolve-path')

const addons = []

let baseUrl = process.env.VUE_APP_CLI_UI_URL
if (typeof baseUrl === 'undefined') {
  baseUrl = `http://localhost:${process.env.VUE_APP_GRAPHQL_PORT}`
} else {
  baseUrl = baseUrl.replace(/ws:\/\/([a-z0-9_-]+:\d+).*/i, 'http://$1')
}

function list (context) {
  return addons
}

function add (options, context) {
  if (findOne(options.id)) remove(options.id, context)

  addons.push(options)
  context.pubsub.publish(channels.CLIENT_ADDON_ADDED, {
    clientAddonAdded: options
  })
}

function findOne (id, context = null) {
  return addons.find(
    addon => addon.id === id
  )
}

function remove (id, context) {
  const index = addons.findIndex(
    addon => addon.id === id
  )
  if (index !== -1) addons.splice(index, 1)
}

function clear (context) {
  for (const addon of addons) {
    remove(addon.id, context)
  }
}

function getUrl (addon, context) {
  return addon.url || `${baseUrl}/_addon/${addon.id}/index.js`
}

function serve (req, res) {
  const { id, 0: file } = req.params
  const addon = findOne(decodeURIComponent(id))
  if (addon && addon.path) {
    const resolvedPath = require.resolve(addon.path)
    const basePath = resolveModuleRoot(resolvedPath)
    if (basePath) {
      res.sendFile(path.join(basePath, file), { maxAge: 0 })
    } else {
      res.status(404)
      res.send(`File not found (resolved: ${resolvedPath}`)
    }
  } else {
    res.status(404)
    res.send(`Addon ${id} not found in loaded addons. Try opening a vue-cli project first?`)
  }
}

module.exports = {
  list,
  add,
  remove,
  findOne,
  getUrl,
  serve,
  clear
}