gecko/toolkit/modules/sessionstore/FormData.jsm
2014-08-19 17:27:58 -07:00

420 lines
13 KiB
JavaScript

/* 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";
this.EXPORTED_SYMBOLS = ["FormData"];
const Cu = Components.utils;
const Ci = Components.interfaces;
Cu.import("resource://gre/modules/Timer.jsm");
Cu.import("resource://gre/modules/XPathGenerator.jsm");
/**
* Returns whether the given URL very likely has input
* fields that contain serialized session store data.
*/
function isRestorationPage(url) {
return url == "about:sessionrestore" || url == "about:welcomeback";
}
/**
* Returns whether the given form |data| object contains nested restoration
* data for a page like about:sessionrestore or about:welcomeback.
*/
function hasRestorationData(data) {
if (isRestorationPage(data.url) && data.id) {
return typeof(data.id.sessionData) == "object";
}
return false;
}
/**
* Returns the given document's current URI and strips
* off the URI's anchor part, if any.
*/
function getDocumentURI(doc) {
return doc.documentURI.replace(/#.*$/, "");
}
/**
* Returns whether the given value is a valid credit card number based on
* the Luhn algorithm. See https://en.wikipedia.org/wiki/Luhn_algorithm.
*/
function isValidCCNumber(value) {
// Remove dashes and whitespace.
let ccNumber = value.replace(/[-\s]+/g, "");
// Check for non-alphanumeric characters.
if (/[^0-9]/.test(ccNumber)) {
return false;
}
// Check for invalid length.
let length = ccNumber.length;
if (length != 9 && length != 15 && length != 16) {
return false;
}
let total = 0;
for (let i = 0; i < length; i++) {
let currentChar = ccNumber.charAt(length - i - 1);
let currentDigit = parseInt(currentChar, 10);
if (i % 2) {
// Double every other value.
total += currentDigit * 2;
// If the doubled value has two digits, add the digits together.
if (currentDigit > 4) {
total -= 9;
}
} else {
total += currentDigit;
}
}
return total % 10 == 0;
}
/**
* The public API exported by this module that allows to collect
* and restore form data for a document and its subframes.
*/
this.FormData = Object.freeze({
collect: function (frame) {
return FormDataInternal.collect(frame);
},
restore: function (frame, data) {
FormDataInternal.restore(frame, data);
},
restoreTree: function (root, data) {
FormDataInternal.restoreTree(root, data);
}
});
/**
* This module's internal API.
*/
let FormDataInternal = {
/**
* Collect form data for a given |frame| *not* including any subframes.
*
* The returned object may have an "id", "xpath", or "innerHTML" key or a
* combination of those three. Form data stored under "id" is for input
* fields with id attributes. Data stored under "xpath" is used for input
* fields that don't have a unique id and need to be queried using XPath.
* The "innerHTML" key is used for editable documents (designMode=on).
*
* Example:
* {
* id: {input1: "value1", input3: "value3"},
* xpath: {
* "/xhtml:html/xhtml:body/xhtml:input[@name='input2']" : "value2",
* "/xhtml:html/xhtml:body/xhtml:input[@name='input4']" : "value4"
* }
* }
*
* @param doc
* DOMDocument instance to obtain form data for.
* @return object
* Form data encoded in an object.
*/
collect: function ({document: doc}) {
let formNodes = doc.evaluate(
XPathGenerator.restorableFormNodes,
doc,
XPathGenerator.resolveNS,
Ci.nsIDOMXPathResult.UNORDERED_NODE_ITERATOR_TYPE, null
);
let node;
let ret = {};
// Limit the number of XPath expressions for performance reasons. See
// bug 477564.
const MAX_TRAVERSED_XPATHS = 100;
let generatedCount = 0;
while ((node = formNodes.iterateNext())) {
let hasDefaultValue = true;
let value;
// Only generate a limited number of XPath expressions for perf reasons
// (cf. bug 477564)
if (!node.id && generatedCount > MAX_TRAVERSED_XPATHS) {
continue;
}
// We do not want to collect credit card numbers.
if (node instanceof Ci.nsIDOMHTMLInputElement &&
isValidCCNumber(node.value)) {
continue;
}
if (node instanceof Ci.nsIDOMHTMLInputElement ||
node instanceof Ci.nsIDOMHTMLTextAreaElement ||
node instanceof Ci.nsIDOMXULTextBoxElement) {
switch (node.type) {
case "checkbox":
case "radio":
value = node.checked;
hasDefaultValue = value == node.defaultChecked;
break;
case "file":
value = { type: "file", fileList: node.mozGetFileNameArray() };
hasDefaultValue = !value.fileList.length;
break;
default: // text, textarea
value = node.value;
hasDefaultValue = value == node.defaultValue;
break;
}
} else if (!node.multiple) {
// <select>s without the multiple attribute are hard to determine the
// default value, so assume we don't have the default.
hasDefaultValue = false;
value = { selectedIndex: node.selectedIndex, value: node.value };
} else {
// <select>s with the multiple attribute are easier to determine the
// default value since each <option> has a defaultSelected property
let options = Array.map(node.options, opt => {
hasDefaultValue = hasDefaultValue && (opt.selected == opt.defaultSelected);
return opt.selected ? opt.value : -1;
});
value = options.filter(ix => ix > -1);
}
// In order to reduce XPath generation (which is slow), we only save data
// for form fields that have been changed. (cf. bug 537289)
if (hasDefaultValue) {
continue;
}
if (node.id) {
ret.id = ret.id || {};
ret.id[node.id] = value;
} else {
generatedCount++;
ret.xpath = ret.xpath || {};
ret.xpath[XPathGenerator.generate(node)] = value;
}
}
// designMode is undefined e.g. for XUL documents (as about:config)
if ((doc.designMode || "") == "on" && doc.body) {
ret.innerHTML = doc.body.innerHTML;
}
// Return |null| if no form data has been found.
if (Object.keys(ret).length === 0) {
return null;
}
// Store the frame's current URL with its form data so that we can compare
// it when restoring data to not inject form data into the wrong document.
ret.url = getDocumentURI(doc);
// We want to avoid saving data for about:sessionrestore as a string.
// Since it's stored in the form as stringified JSON, stringifying further
// causes an explosion of escape characters. cf. bug 467409
if (isRestorationPage(ret.url)) {
ret.id.sessionData = JSON.parse(ret.id.sessionData);
}
return ret;
},
/**
* Restores form |data| for the given frame. The data is expected to be in
* the same format that FormData.collect() returns.
*
* @param frame (DOMWindow)
* The frame to restore form data to.
* @param data (object)
* An object holding form data.
*/
restore: function ({document: doc}, data) {
// Don't restore any data for the given frame if the URL
// stored in the form data doesn't match its current URL.
if (!data.url || data.url != getDocumentURI(doc)) {
return;
}
// For about:{sessionrestore,welcomeback} we saved the field as JSON to
// avoid nested instances causing humongous sessionstore.js files.
// cf. bug 467409
if (hasRestorationData(data)) {
data.id.sessionData = JSON.stringify(data.id.sessionData);
}
if ("id" in data) {
let retrieveNode = id => doc.getElementById(id);
this.restoreManyInputValues(data.id, retrieveNode);
}
if ("xpath" in data) {
let retrieveNode = xpath => XPathGenerator.resolve(doc, xpath);
this.restoreManyInputValues(data.xpath, retrieveNode);
}
if ("innerHTML" in data) {
// We know that the URL matches data.url right now, but the user
// may navigate away before the setTimeout handler runs. We do
// a simple comparison against savedURL to check for that.
let savedURL = doc.documentURI;
setTimeout(() => {
if (doc.body && doc.designMode == "on" && doc.documentURI == savedURL) {
doc.body.innerHTML = data.innerHTML;
this.fireEvent(doc.body, "input");
}
});
}
},
/**
* Iterates the given form data, retrieving nodes for all the keys and
* restores their appropriate values.
*
* @param data (object)
* A subset of the form data as collected by FormData.collect(). This
* is either data stored under "id" or under "xpath".
* @param retrieve (function)
* The function used to retrieve the input field belonging to a key
* in the given |data| object.
*/
restoreManyInputValues: function (data, retrieve) {
for (let key of Object.keys(data)) {
let input = retrieve(key);
if (input) {
this.restoreSingleInputValue(input, data[key]);
}
}
},
/**
* Restores a given form value to a given DOMNode and takes care of firing
* the appropriate DOM event should the input's value change.
*
* @param aNode
* DOMNode to set form value on.
* @param aValue
* Value to set form element to.
*/
restoreSingleInputValue: function (aNode, aValue) {
let eventType;
if (typeof aValue == "string" && aNode.type != "file") {
// Don't dispatch an input event if there is no change.
if (aNode.value == aValue) {
return;
}
aNode.value = aValue;
eventType = "input";
} else if (typeof aValue == "boolean") {
// Don't dispatch a change event for no change.
if (aNode.checked == aValue) {
return;
}
aNode.checked = aValue;
eventType = "change";
} else if (aValue && aValue.selectedIndex >= 0 && aValue.value) {
// Don't dispatch a change event for no change
if (aNode.options[aNode.selectedIndex].value == aValue.value) {
return;
}
// find first option with matching aValue if possible
for (let i = 0; i < aNode.options.length; i++) {
if (aNode.options[i].value == aValue.value) {
aNode.selectedIndex = i;
eventType = "change";
break;
}
}
} else if (aValue && aValue.fileList && aValue.type == "file" &&
aNode.type == "file") {
aNode.mozSetFileNameArray(aValue.fileList, aValue.fileList.length);
eventType = "input";
} else if (Array.isArray(aValue) && aNode.options) {
Array.forEach(aNode.options, function(opt, index) {
// don't worry about malformed options with same values
opt.selected = aValue.indexOf(opt.value) > -1;
// Only fire the event here if this wasn't selected by default
if (!opt.defaultSelected) {
eventType = "change";
}
});
}
// Fire events for this node if applicable
if (eventType) {
this.fireEvent(aNode, eventType);
}
},
/**
* Dispatches an event of type |type| to the given |node|.
*
* @param node (DOMNode)
* @param type (string)
*/
fireEvent: function (node, type) {
let doc = node.ownerDocument;
let event = doc.createEvent("UIEvents");
event.initUIEvent(type, true, true, doc.defaultView, 0);
node.dispatchEvent(event);
},
/**
* Restores form data for the current frame hierarchy starting at |root|
* using the given form |data|.
*
* If the given |root| frame's hierarchy doesn't match that of the given
* |data| object we will silently discard data for unreachable frames. For
* security reasons we will never restore form data to the wrong frames as
* we bail out silently if the stored URL doesn't match the frame's current
* URL.
*
* @param root (DOMWindow)
* @param data (object)
* {
* formdata: {id: {input1: "value1"}},
* children: [
* {formdata: {id: {input2: "value2"}}},
* null,
* {formdata: {xpath: { ... }}, children: [ ... ]}
* ]
* }
*/
restoreTree: function (root, data) {
// Don't restore any data for the root frame and its subframes if there
// is a URL stored in the form data and it doesn't match its current URL.
if (data.url && data.url != getDocumentURI(root.document)) {
return;
}
if (data.url) {
this.restore(root, data);
}
if (!data.hasOwnProperty("children")) {
return;
}
let frames = root.frames;
for (let index of Object.keys(data.children)) {
if (index < frames.length) {
this.restoreTree(frames[index], data.children[index]);
}
}
}
};