overleaf/services/web/frontend/js/services/queued-http.js

/* eslint-disable
    max-len,
*/
// TODO: This file was created by bulk-decaffeinate.
// Fix any style issues and re-enable lint.
/*
 * decaffeinate suggestions:
 * DS101: Remove unnecessary use of Array.from
 * DS102: Remove unnecessary code created because of implicit returns
 * DS207: Consider shorter variations of null checks
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
import App from '../base'

export default App.factory('queuedHttp', function($http, $q) {
  const pendingRequests = []
  let inflight = false

  var processPendingRequests = function() {
    if (inflight) {
      return
    }
    const doRequest = pendingRequests.shift()
    if (doRequest != null) {
      inflight = true
      return doRequest()
        .then(function() {
          inflight = false
          return processPendingRequests()
        })
        .catch(function() {
          inflight = false
          return processPendingRequests()
        })
    }
  }

  const queuedHttp = function(...args) {
    // We can't use Angular's $q.defer promises, because it only passes
    // a single argument on error, and $http passes multiple.
    const promise = {}
    const successCallbacks = []
    const errorCallbacks = []

    // Adhere to the $http promise conventions
    promise.then = function(callback, errCallback) {
      successCallbacks.push(callback)
      if (errCallback != null) {
        errorCallbacks.push(errCallback)
      }
      return promise
    }

    promise.catch = function(callback) {
      errorCallbacks.push(callback)
      return promise
    }

    const doRequest = () =>
      $http(...Array.from(args || []))
        .then((...args) =>
          Array.from(successCallbacks).map(cb => cb(...Array.from(args || [])))
        )
        .catch((...args) =>
          Array.from(errorCallbacks).map(cb => cb(...Array.from(args || [])))
        )

    pendingRequests.push(doRequest)
    processPendingRequests()

    return promise
  }

  queuedHttp.post = (url, data) => queuedHttp({ method: 'POST', url, data })

  return queuedHttp
})