Add ErrorConsole UI for Extension Install Warnings

chrome/browser/resources/extensions/extension_error.js

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+cr.define('extensions', function() {
+  'use strict';
+
+  /**
+   * Returns whether or not a given |url| is associated with an extension.
+   * @param {string} url The url to examine.
+   * @param {string} extensionUrl The url of the extension.
+   * @return {boolean} Whether or not the url is associated with the extension.
+   */
+  function isExtensionUrl(url, extensionUrl) {
+    return url.substring(0, extensionUrl.length) == extensionUrl;
+  }
+
+  /**
+   * Get the url relative to the main extension url. If the url is
+   * unassociated with the extension, this will be the full url.
+   * @param {string} url The url to make relative.
+   * @param {string} extensionUrl The host for which the url is relative.
+   * @return {string} The url relative to the host.
+   */
+  function getRelativeUrl(url, extensionUrl) {
+    return isExtensionUrl(url, extensionUrl) ?
+        url.substring(extensionUrl.length) : url;
+  }
+
+  /**
+   * Clone a template within the extension error template collection.
+   * @param {string} templateName The class name of the template to clone.
+   * @return {HTMLElement} The clone of the template.
+   */
+  function cloneTemplate(templateName) {
+    return $('template-collection-extension-error').
+        querySelector(templateName).cloneNode(true);

[Dan Beam, 2013/08/29 00:24:30]

maybe: querySelector('.' + templateName) and remove '.' from everywhere else?

[Devlin, 2013/08/29 21:02:04]

Done.

+  }
+
+  /**
+   * Creates a new ExtensionError HTMLElement.

[Dan Beam, 2013/08/29 00:24:30]

^ this is kind of a lacking description.  what does this do?  maybe, "Used to
show a notification when extension errors occur." (or something like that).

[Devlin, 2013/08/29 21:02:04]

Done.

+   * @param {Object} error The error the element should represent.
+   * @constructor
+   * @extends {HTMLDivElement}
+   */
+  function ExtensionError(error) {
+    var div = document.createElement('div');
+    div.__proto__ = ExtensionError.prototype;
+    div.className = 'extension-error-simple-wrapper';
+    div.error_ = error;
+    div.decorate();
+    return div;
+  }
+
+  ExtensionError.prototype = {
+    __proto__: HTMLDivElement.prototype,
+
+    /** @override */
+    decorate: function() {
+      var metadata = cloneTemplate('.extension-error-metadata');
+
+      // Add an additional class for the severity level.
+      if (this.error_.level == 0)
+        metadata.className += ' extension-error-log';
+      else if (this.error_.level == 1)
+        metadata.className += ' extension-error-warn';
+      else
+        metadata.className += ' extension-error-error';
+
+      // Add a property for the extension's base url in order to determine if
+      // a url belongs to the extension.
+      this.extensionUrl_ =
+          'chrome-extension://' + this.error_.extensionId + '/';
+
+      metadata.querySelector('.extension-error-message').innerText =
+          this.error_.message;
+
+      metadata.appendChild(this.getViewSourceOrPlain_(
+          '(' + getRelativeUrl(this.error_.source, this.extensionUrl_) + ')',
+          this.error_.source));
+
+      this.appendChild(metadata);
+    },
+
+    /**
+     * If it's possible to view the source for the given |url|, then return a
+     * link to do so. Otherwise, return a plain-text node.

[Dan Beam, 2013/08/29 00:24:30]

^ is this still returning a text node?

[Devlin, 2013/08/29 21:02:04]

Yeah - it returns a div with just plain text (and no link) if we can't view the
source.  I revised the comment to make it a bit more clear.

+     * @param {string} description The innerText of the node to create;
+     *     a human-friendly description the location (e.g., filename, line).

[Dan Beam, 2013/08/29 00:24:30]

nit: i think it'd be better to just explain what should be passed with @param,
not exactly how it's used.

  @param {string} description A human-friendly description the location (e.g.,
filename, line).

[Devlin, 2013/08/29 21:02:04]

Done.

+     * @param {string} url The url of the resource to view.
+     * @return {HTMLElement} The created node, either a link or plaintext.
+     * @private
+     */
+    getViewSourceOrPlain_: function(description, url) {
+      if (this.canViewSource_(url)) {

[Dan Beam, 2013/08/29 00:24:30]

nit: no curlies

[Devlin, 2013/08/29 21:02:04]

Done.

+        var node = this.getViewSourceLink_(url);
+      } else {
+        var node = document.createElement('div');
+      }
+      node.className = 'extension-error-view-source';

[Dan Beam, 2013/08/29 00:24:30]

what does setting the classname of a text node do?

[Devlin, 2013/08/29 21:02:04]

It's so the css can take effect.  Right now, there's only one property for the
class, but I thought it better to have all style in the css, when possible.

+      node.innerText = description;
+      return node;
+    },
+
+    /**
+     * Determine whether we can view the source of a given url.
+     * @param {string} url The url to the resource to view.

[Dan Beam, 2013/08/29 00:24:30]

nit: the url _of_ the resource to view?

[Devlin, 2013/08/29 21:02:04]

Done.

+     * @return {boolean} Whether or not we can view the source for the url.
+     * @private
+     */
+    canViewSource_: function(url) {
+      return isExtensionUrl(url, this.extensionUrl_) || url == 'manifest.json';
+    },
+
+    /**
+     * Create a clickable node to view the source for the given url.
+     * @param {string} url The url to the resource to view.
+     * @return {HTMLElement} The clickable node to view the source.
+     * @private
+     */
+    getViewSourceLink_: function(url) {
+      var node = document.createElement('a');
+      var relativeUrl = getRelativeUrl(url, this.extensionUrl_);
+
+      node.addEventListener('click', function(e) {
+        chrome.send('extensionErrorRequestFileSource',
+                    [{'extensionId': this.error_.extensionId,
+                      'errorMessage': this.error_.message,
+                      'fileType': 'manifest',
+                      'pathSuffix': relativeUrl,
+                      'feature': this.error_.manifestKey,
+                      'specific': this.error_.manifestSpecific}]);
+      }.bind(this));
+      return node;
+    },
+  };
+
+  /**
+   * An ExtensionErrorList represents the list of either runtime or manifest
+   * errors for a given extension. Each item in the list is an ExtensionError
+   * object, with information about the error. The list will display up to
+   * |MAX_ERRORS_TO_SHOW_| errors, with the option to expand (and then shrink)
+   * the displayed portion. This is included as part of the Extension node in
+   * the ExtensionList in chrome://extensions, if errors are present.

[Dan Beam, 2013/08/29 00:24:30]

nit: this whole paragraph could be shortened to:

  A variable length list of runtime or manifest errors for a given extension.

IMO

[Devlin, 2013/08/29 21:02:04]

Done.

+   * @constructor
+   * @extends {HTMLDivElement}
+   */
+  function ExtensionErrorList(errors) {
+    var div = cloneTemplate('.extension-error-list');
+    div.__proto__ = ExtensionErrorList.prototype;
+    div.errors_ = errors;
+    div.decorate();
+    return div;
+  }
+
+  ExtensionErrorList.prototype = {
+    __proto__: HTMLDivElement.prototype,
+
+    /**
+     * @private
+     * @const
+     * @type {number}
+     */
+    MAX_ERRORS_TO_SHOW_: 3,
+
+    /** @override */
+    decorate: function() {
+      this.contents_ = this.querySelector('.extension-error-list-contents');
+      this.errors_.forEach(function(error) {
+        this.contents_.appendChild(document.createElement('li')).appendChild(
+            new ExtensionError(error));
+      }, this);
+
+      if (this.contents_.children.length > this.MAX_ERRORS_TO_SHOW_) {
+        for (var i = this.MAX_ERRORS_TO_SHOW_;
+             i < this.contents_.children.length; ++i) {
+          this.contents_.children[i].hidden = true;
+        }
+        this.initShowMoreButton_();
+      }
+    },
+
+    /**
+     * Initialize the "Show More" button for the error list, if there are more

[Dan Beam, 2013/08/29 00:24:30]

nit: Initialize the "Show More" button for the error list. If there are more...

[Devlin, 2013/08/29 21:02:04]

Done.

+     * than |MAX_ERRORS_TO_SHOW_| errors in the list.
+     * @private
+     */
+    initShowMoreButton_: function() {
+      var button = this.querySelector('.extension-error-list-show-more a');
+      button.hidden = false;
+      button.isShowingAll = false;
+      button.addEventListener('click', function(e) {
+        for (var i = this.MAX_ERRORS_TO_SHOW_;
+             i < this.contents_.children.length; ++i) {
+          this.contents_.children[i].hidden = button.isShowingAll;
+        }
+        var message = button.isShowingAll ? 'extensionErrorsShowMore' :
+                                            'extensionErrorsShowFewer';
+        button.innerText = loadTimeData.getString(message);
+        button.isShowingAll = !button.isShowingAll;
+      }.bind(this));
+    }
+  };
+
+  return {
+    ExtensionErrorList: ExtensionErrorList
+  };
+});