DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (6c6c67870c37)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537
/* 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/. */

/**
 * Provides collections of Download objects and aggregate views on them.
 */

"use strict";

var EXPORTED_SYMBOLS = [
  "DownloadList",
  "DownloadCombinedList",
  "DownloadSummary",
];

/**
 * Represents a collection of Download objects that can be viewed and managed by
 * the user interface, and persisted across sessions.
 */
var DownloadList = function() {
  this._downloads = [];
  this._views = new Set();
};

DownloadList.prototype = {
  /**
   * Array of Download objects currently in the list.
   */
  _downloads: null,

  /**
   * Retrieves a snapshot of the downloads that are currently in the list.  The
   * returned array does not change when downloads are added or removed, though
   * the Download objects it contains are still updated in real time.
   *
   * @return {Promise}
   * @resolves An array of Download objects.
   * @rejects JavaScript exception.
   */
  getAll: function DL_getAll() {
    return Promise.resolve(Array.from(this._downloads));
  },

  /**
   * Adds a new download to the end of the items list.
   *
   * @note When a download is added to the list, its "onchange" event is
   *       registered by the list, thus it cannot be used to monitor the
   *       download.  To receive change notifications for downloads that are
   *       added to the list, use the addView method to register for
   *       onDownloadChanged notifications.
   *
   * @param aDownload
   *        The Download object to add.
   *
   * @return {Promise}
   * @resolves When the download has been added.
   * @rejects JavaScript exception.
   */
  add: function DL_add(aDownload) {
    this._downloads.push(aDownload);
    aDownload.onchange = this._change.bind(this, aDownload);
    this._notifyAllViews("onDownloadAdded", aDownload);

    return Promise.resolve();
  },

  /**
   * Removes a download from the list.  If the download was already removed,
   * this method has no effect.
   *
   * This method does not change the state of the download, to allow adding it
   * to another list, or control it directly.  If you want to dispose of the
   * download object, you should cancel it afterwards, and remove any partially
   * downloaded data if needed.
   *
   * @param aDownload
   *        The Download object to remove.
   *
   * @return {Promise}
   * @resolves When the download has been removed.
   * @rejects JavaScript exception.
   */
  remove: function DL_remove(aDownload) {
    let index = this._downloads.indexOf(aDownload);
    if (index != -1) {
      this._downloads.splice(index, 1);
      aDownload.onchange = null;
      this._notifyAllViews("onDownloadRemoved", aDownload);
    }

    return Promise.resolve();
  },

  /**
   * This function is called when "onchange" events of downloads occur.
   *
   * @param aDownload
   *        The Download object that changed.
   */
  _change: function DL_change(aDownload) {
    this._notifyAllViews("onDownloadChanged", aDownload);
  },

  /**
   * Set of currently registered views.
   */
  _views: null,

  /**
   * Adds a view that will be notified of changes to downloads.  The newly added
   * view will receive onDownloadAdded notifications for all the downloads that
   * are already in the list.
   *
   * @param aView
   *        The view object to add.  The following methods may be defined:
   *        {
   *          onDownloadAdded: function (aDownload) {
   *            // Called after aDownload is added to the end of the list.
   *          },
   *          onDownloadChanged: function (aDownload) {
   *            // Called after the properties of aDownload change.
   *          },
   *          onDownloadRemoved: function (aDownload) {
   *            // Called after aDownload is removed from the list.
   *          },
   *          onDownloadBatchStarting: function () {
   *            // Called before multiple changes are made at the same time.
   *          },
   *          onDownloadBatchEnded: function () {
   *            // Called after all the changes have been made.
   *          },
   *        }
   *
   * @return {Promise}
   * @resolves When the view has been registered and all the onDownloadAdded
   *           notifications for the existing downloads have been sent.
   * @rejects JavaScript exception.
   */
  addView: function DL_addView(aView) {
    this._views.add(aView);

    if ("onDownloadAdded" in aView) {
      this._notifyAllViews("onDownloadBatchStarting");
      for (let download of this._downloads) {
        try {
          aView.onDownloadAdded(download);
        } catch (ex) {
          Cu.reportError(ex);
        }
      }
      this._notifyAllViews("onDownloadBatchEnded");
    }

    return Promise.resolve();
  },

  /**
   * Removes a view that was previously added using addView.
   *
   * @param aView
   *        The view object to remove.
   *
   * @return {Promise}
   * @resolves When the view has been removed.  At this point, the removed view
   *           will not receive any more notifications.
   * @rejects JavaScript exception.
   */
  removeView: function DL_removeView(aView) {
    this._views.delete(aView);

    return Promise.resolve();
  },

  /**
   * Notifies all the views of a download addition, change, removal, or other
   * event. The additional arguments are passed to the called method.
   *
   * @param methodName
   *        String containing the name of the method to call on the view.
   */
  _notifyAllViews(methodName, ...args) {
    for (let view of this._views) {
      try {
        if (methodName in view) {
          view[methodName](...args);
        }
      } catch (ex) {
        Cu.reportError(ex);
      }
    }
  },

  /**
   * Removes downloads from the list that have finished, have failed, or have
   * been canceled without keeping partial data.  A filter function may be
   * specified to remove only a subset of those downloads.
   *
   * This method finalizes each removed download, ensuring that any partially
   * downloaded data associated with it is also removed.
   *
   * @param aFilterFn
   *        The filter function is called with each download as its only
   *        argument, and should return true to remove the download and false
   *        to keep it.  This parameter may be null or omitted to have no
   *        additional filter.
   */
  removeFinished: function DL_removeFinished(aFilterFn) {
    (async () => {
      let list = await this.getAll();
      for (let download of list) {
        // Remove downloads that have been canceled, even if the cancellation
        // operation hasn't completed yet so we don't check "stopped" here.
        // Failed downloads with partial data are also removed.
        if (
          download.stopped &&
          (!download.hasPartialData || download.error) &&
          (!aFilterFn || aFilterFn(download))
        ) {
          // Remove the download first, so that the views don't get the change
          // notifications that may occur during finalization.
          await this.remove(download);
          // Ensure that the download is stopped and no partial data is kept.
          // This works even if the download state has changed meanwhile.  We
          // don't need to wait for the procedure to be complete before
          // processing the other downloads in the list.
          download.finalize(true).catch(Cu.reportError);
        }
      }
    })().catch(Cu.reportError);
  },
};

/**
 * Provides a unified, unordered list combining public and private downloads.
 *
 * Download objects added to this list are also added to one of the two
 * underlying lists, based on their "source.isPrivate" property.  Views on this
 * list will receive notifications for both public and private downloads.
 *
 * @param aPublicList
 *        Underlying DownloadList containing public downloads.
 * @param aPrivateList
 *        Underlying DownloadList containing private downloads.
 */
var DownloadCombinedList = function(aPublicList, aPrivateList) {
  DownloadList.call(this);
  this._publicList = aPublicList;
  this._privateList = aPrivateList;
  aPublicList.addView(this).catch(Cu.reportError);
  aPrivateList.addView(this).catch(Cu.reportError);
};

DownloadCombinedList.prototype = {
  __proto__: DownloadList.prototype,

  /**
   * Underlying DownloadList containing public downloads.
   */
  _publicList: null,

  /**
   * Underlying DownloadList containing private downloads.
   */
  _privateList: null,

  /**
   * Adds a new download to the end of the items list.
   *
   * @note When a download is added to the list, its "onchange" event is
   *       registered by the list, thus it cannot be used to monitor the
   *       download.  To receive change notifications for downloads that are
   *       added to the list, use the addView method to register for
   *       onDownloadChanged notifications.
   *
   * @param aDownload
   *        The Download object to add.
   *
   * @return {Promise}
   * @resolves When the download has been added.
   * @rejects JavaScript exception.
   */
  add(aDownload) {
    if (aDownload.source.isPrivate) {
      return this._privateList.add(aDownload);
    }
    return this._publicList.add(aDownload);
  },

  /**
   * Removes a download from the list.  If the download was already removed,
   * this method has no effect.
   *
   * This method does not change the state of the download, to allow adding it
   * to another list, or control it directly.  If you want to dispose of the
   * download object, you should cancel it afterwards, and remove any partially
   * downloaded data if needed.
   *
   * @param aDownload
   *        The Download object to remove.
   *
   * @return {Promise}
   * @resolves When the download has been removed.
   * @rejects JavaScript exception.
   */
  remove(aDownload) {
    if (aDownload.source.isPrivate) {
      return this._privateList.remove(aDownload);
    }
    return this._publicList.remove(aDownload);
  },

  // DownloadList callback
  onDownloadAdded(aDownload) {
    this._downloads.push(aDownload);
    this._notifyAllViews("onDownloadAdded", aDownload);
  },

  // DownloadList callback
  onDownloadChanged(aDownload) {
    this._notifyAllViews("onDownloadChanged", aDownload);
  },

  // DownloadList callback
  onDownloadRemoved(aDownload) {
    let index = this._downloads.indexOf(aDownload);
    if (index != -1) {
      this._downloads.splice(index, 1);
    }
    this._notifyAllViews("onDownloadRemoved", aDownload);
  },
};

/**
 * Provides an aggregated view on the contents of a DownloadList.
 */
var DownloadSummary = function() {
  this._downloads = [];
  this._views = new Set();
};

DownloadSummary.prototype = {
  /**
   * Array of Download objects that are currently part of the summary.
   */
  _downloads: null,

  /**
   * Underlying DownloadList whose contents should be summarized.
   */
  _list: null,

  /**
   * This method may be called once to bind this object to a DownloadList.
   *
   * Views on the summarized data can be registered before this object is bound
   * to an actual list.  This allows the summary to be used without requiring
   * the initialization of the DownloadList first.
   *
   * @param aList
   *        Underlying DownloadList whose contents should be summarized.
   *
   * @return {Promise}
   * @resolves When the view on the underlying list has been registered.
   * @rejects JavaScript exception.
   */
  bindToList(aList) {
    if (this._list) {
      throw new Error("bindToList may be called only once.");
    }

    return aList.addView(this).then(() => {
      // Set the list reference only after addView has returned, so that we don't
      // send a notification to our views for each download that is added.
      this._list = aList;
      this._onListChanged();
    });
  },

  /**
   * Set of currently registered views.
   */
  _views: null,

  /**
   * Adds a view that will be notified of changes to the summary.  The newly
   * added view will receive an initial onSummaryChanged notification.
   *
   * @param aView
   *        The view object to add.  The following methods may be defined:
   *        {
   *          onSummaryChanged: function () {
   *            // Called after any property of the summary has changed.
   *          },
   *        }
   *
   * @return {Promise}
   * @resolves When the view has been registered and the onSummaryChanged
   *           notification has been sent.
   * @rejects JavaScript exception.
   */
  addView(aView) {
    this._views.add(aView);

    if ("onSummaryChanged" in aView) {
      try {
        aView.onSummaryChanged();
      } catch (ex) {
        Cu.reportError(ex);
      }
    }

    return Promise.resolve();
  },

  /**
   * Removes a view that was previously added using addView.
   *
   * @param aView
   *        The view object to remove.
   *
   * @return {Promise}
   * @resolves When the view has been removed.  At this point, the removed view
   *           will not receive any more notifications.
   * @rejects JavaScript exception.
   */
  removeView(aView) {
    this._views.delete(aView);

    return Promise.resolve();
  },

  /**
   * Indicates whether all the downloads are currently stopped.
   */
  allHaveStopped: true,

  /**
   * Indicates whether whether all downloads have an unknown final size.
   */
  allUnknownSize: true,

  /**
   * Indicates the total number of bytes to be transferred before completing all
   * the downloads that are currently in progress.
   *
   * For downloads that do not have a known final size, the number of bytes
   * currently transferred is reported as part of this property.
   *
   * This is zero if no downloads are currently in progress.
   */
  progressTotalBytes: 0,

  /**
   * Number of bytes currently transferred as part of all the downloads that are
   * currently in progress.
   *
   * This is zero if no downloads are currently in progress.
   */
  progressCurrentBytes: 0,

  /**
   * This function is called when any change in the list of downloads occurs,
   * and will recalculate the summary and notify the views in case the
   * aggregated properties are different.
   */
  _onListChanged() {
    let allHaveStopped = true;
    let allUnknownSize = true;
    let progressTotalBytes = 0;
    let progressCurrentBytes = 0;

    // Recalculate the aggregated state.  See the description of the individual
    // properties for an explanation of the summarization logic.
    for (let download of this._downloads) {
      if (!download.stopped) {
        allHaveStopped = false;
        if (download.hasProgress) {
          allUnknownSize = false;
          progressTotalBytes += download.totalBytes;
        } else {
          progressTotalBytes += download.currentBytes;
        }
        progressCurrentBytes += download.currentBytes;
      }
    }

    // Exit now if the properties did not change.
    if (
      this.allHaveStopped == allHaveStopped &&
      this.allUnknownSize == allUnknownSize &&
      this.progressTotalBytes == progressTotalBytes &&
      this.progressCurrentBytes == progressCurrentBytes
    ) {
      return;
    }

    this.allHaveStopped = allHaveStopped;
    this.allUnknownSize = allUnknownSize;
    this.progressTotalBytes = progressTotalBytes;
    this.progressCurrentBytes = progressCurrentBytes;

    // Notify all the views that our properties changed.
    for (let view of this._views) {
      try {
        if ("onSummaryChanged" in view) {
          view.onSummaryChanged();
        }
      } catch (ex) {
        Cu.reportError(ex);
      }
    }
  },

  // DownloadList callback
  onDownloadAdded(aDownload) {
    this._downloads.push(aDownload);
    if (this._list) {
      this._onListChanged();
    }
  },

  // DownloadList callback
  onDownloadChanged(aDownload) {
    this._onListChanged();
  },

  // DownloadList callback
  onDownloadRemoved(aDownload) {
    let index = this._downloads.indexOf(aDownload);
    if (index != -1) {
      this._downloads.splice(index, 1);
    }
    this._onListChanged();
  },
};