refactor_middleware_for_workers.js

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

"use strict";

const {
  DEBUG_TARGETS,
  REQUEST_WORKERS_SUCCESS,
  SERVICE_WORKER_FETCH_STATES,
  SERVICE_WORKER_STATUSES,
} = require("../constants");

/**
 * This middleware converts workers object that get from DebuggerClient.listAllWorkers()
 * to data which is used in DebugTargetItem.
 */
const workerComponentDataMiddleware = store => next => action => {
  switch (action.type) {
    case REQUEST_WORKERS_SUCCESS: {
      action.otherWorkers = toComponentData(action.otherWorkers);
      action.serviceWorkers = toComponentData(action.serviceWorkers, true);
      action.sharedWorkers = toComponentData(action.sharedWorkers);
      break;
    }
  }

  return next(action);
};

function getServiceWorkerStatus(isActive, isRunning) {
  if (isActive && isRunning) {
    return SERVICE_WORKER_STATUSES.RUNNING;
  } else if (isActive) {
    return SERVICE_WORKER_STATUSES.STOPPED;
  }
  // We cannot get service worker registrations unless the registration is in
  // ACTIVE state. Unable to know the actual state ("installing", "waiting"), we
  // display a custom state "registering" for now. See Bug 1153292.
  return SERVICE_WORKER_STATUSES.REGISTERING;
}

function getServiceWorkerDetails(worker) {
  const isActive = worker.active;
  const isRunning = !!worker.workerTargetFront;
  return {
    fetch: worker.fetch ? SERVICE_WORKER_FETCH_STATES.LISTENING
                        : SERVICE_WORKER_FETCH_STATES.NOT_LISTENING,
    isActive,
    isRunning,
    registrationActor: worker.registrationActor,
    scope: worker.scope,
    status: getServiceWorkerStatus(isActive, isRunning),
    subscription: worker.subscription,
  };
}

function toComponentData(workers, isServiceWorker) {
  return workers.map(worker => {
    // Here `worker` is the worker object created by RootFront.listAllWorkers
    const type = DEBUG_TARGETS.WORKER;
    const icon = "chrome://devtools/skin/images/debugging-workers.svg";
    const { name, registrationActor, workerTargetFront } = worker;

    // For registering service workers, workerTargetFront will not be available.
    // The only valid identifier we can use at that point is the actorID for the
    // service worker registration.
    const id = workerTargetFront ? workerTargetFront.actorID : registrationActor;

    return {
      details: isServiceWorker ? getServiceWorkerDetails(worker) : {},
      icon,
      id,
      name,
      type,
    };
  });
}

module.exports = workerComponentDataMiddleware;