I am new to Javascript. I am trying to navigate to a page and "scrape" the screen. I am using Firefox, Greasemonkey and Firebug. I amd trying to use location.href which might be the problem. I want to navigate to a page, parse the contents, use the contents to navigate to other pages. Here is an example (my site is different, but I am getting the same error/result):
location.href='http://www.w3schools.com/html/html_examples.asp';
/* parse and find text */
location.href='http://www.w3schools.com/html/tryit.asp?filename=tryhtml_intro';
alert('finished');
No matter what I do, Firebug/Greasemonkey just quits after the first location.href. The alert will show, but even if I have a breakpoint set there, it will run right past it. Any help is much appreciated.
Scenario 1: A lot of dynamically generated links (fetched with GM_xmlhttpRequest)
//...
//#include http://www.w3schools.com/html/html_examples.asp
//#grant GM_xmlhttpRequest
//...
var urls = [];
//parse text to generate some links on the fly and store them in urls[]
var i = 0, numUrls = urls.length, reportEntries = [], count = 0;
for(; i < numUrls; i++) {
GM_xmlhttpRequest({
method: 'GET',
url: urls[i],
onload: function(response) {
var returnedHtml = response.responseText;
//extract more information from returnedHtml and store it in reportEntries[i]
if(++count >= numUrls) {
//print reportEntries[] to form a report
alert('finished');
}
}
})
}
Note: If you need to save report as a text file to local disk, Greasemonkey is not a viable option as it does not have the privilege to open local files. None the less you can save it to online storage such as pastebin.com.
Scenario 2: Limited number of static links
//...
//#include http://some.landing/page
//#include http://www.w3schools.com/html/html_examples.asp
//#include http://www.w3schools.com/html/tryit.asp?filename=tryhtml_intro
//...
if('http://some.landing/page' == location.href) {
location.href = 'http://www.w3schools.com/html/html_examples.asp';
}
else if('http://www.w3schools.com/html/html_examples.asp' == location.href) {
/* parse and find text */
location.href='http://www.w3schools.com/html/tryit.asp?filename=tryhtml_intro';
}
else if('http://www.w3schools.com/html/tryit.asp?filename=tryhtml_intro' == location.href) {
alert('finished');
}
Related
I am trying to open a few tabs at once from my shopping cart page using Javascript. I have looked at a few similar questions and I already know that you can use several window.open(url) but I'm not really looking forward to that... I currently have this code
function buyAll()
{
$.ajax({
url:'Basket',
type:'POST',
data: { listOfWines : $.toJSON(chosenIds), action : 'buyAll' },
success : function(responseText)
{
for (var i = 0; i < allSliders.length; i++)
{
var cellsCollection = document.getElementById(allSliders[i].id).closest('tr').children;
var row = document.getElementById(allSliders[i].id).closest('tr');
$(cellsCollection)
.animate({ padding: 0 }, 800)
.wrapInner('<div />')
.children()
.slideUp(function() { $(row).remove(); });
}
showSnackOpened();
}
});
for(i = 0; i < allSliders.length; i++)
{
var url = allSliders[i].getAttribute('data-redir');
window.open(url, '_blank');
}
}
Forgive me if the code isn't the best or there's a bit of a mix with the jQuery (JS isn't my best-known language) I take an array of elements on the shopping cart and get a particular attribute of these elements, which is the URL I need to redirect the user to. Once I have the list of URLs I try to iterate over them and open the new tabs. However, the browser obviously blocks the pages from the second onward.
Also, Chrome's tabs API won't be of any use to this project, since not all of the users will be using Chrome.
Any help is much appreciated!
Test page: https://jsfiddle.net/y25rk55w/
On this test page you can see 3 <iframe>'s embeded into each other. Each <iframe> contains a <script> tag in it's <head> tag.
The problem is: only the <script> in the first <iframe> will be loaded by the browser. The other two <script> tags will be present in the dom but the browser will never even try to load them. The problem is not browser specific, it can be reroduced in chrome, firefox, ie. The problem cannot be fixed by adding timeouts or waiting before appending the scripts. It seems to be important that all the iframes have programatically generated content; if you replace this iframes with iframes with actual src links, the problem will disappear.
The question is: how can I actually load a script into iframes 2 and 3?
Full test code:
// It doesn't matter if the scripts exist or not
// Browser won't try to load them either way
var scripts = [
'//testdomain.test/script1.js',
'//testdomain.test/script2.js',
'//testdomain.test/script3.js'
];
function createIFrame(win, onCreated) {
var iframe = win.document.createElement('iframe');
iframe.onload = function () {
onCreated(iframe);
};
win.document.body.appendChild(iframe);
}
function loadScript(win, url) {
var script = win.document.createElement('script');
script.src = url;
script.onload = function() {
console.log("Script " + url + " is loaded.");
};
win.document.getElementsByTagName('head')[0].appendChild(script);
}
createIFrame(window, function(iframe1) {
loadScript(iframe1.contentWindow, scripts[0]);
createIFrame(iframe1.contentWindow, function (iframe2) {
loadScript(iframe2.contentWindow, scripts[1]);
createIFrame(iframe2.contentWindow, function (iframe3) {
loadScript(iframe3.contentWindow, scripts[2]);
});
});
});
Your code is working fine --> http://plnkr.co/edit/vQGsyD7JxZiDlg6EZvK4?p=preview
Make sure you execute createIFrame on window.onload or DOMContentLoaded.
var scripts = [
'https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.1/jquery.js',
'https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.2/jquery.js',
'https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js'
];
function createIFrame(win, onCreated) {
var iframe = win.document.createElement('iframe');
iframe.onload = function () {
onCreated(iframe);
};
win.document.body.appendChild(iframe);
}
function loadScript(win, url) {
var script = win.document.createElement('script');
script.src = url;
script.onload = function() {
console.log("Script " + url + " is loaded.");
};
win.document.getElementsByTagName('head')[0].appendChild(script);
}
window.onload = function(){
createIFrame(window, function(iframe1) {
loadScript(iframe1.contentWindow, scripts[0]);
createIFrame(iframe1.contentWindow, function (iframe2) {
loadScript(iframe2.contentWindow, scripts[1]);
createIFrame(iframe2.contentWindow, function (iframe3) {
loadScript(iframe3.contentWindow, scripts[2]);
});
});
});
};
In the question you can see that I was ommiting the protocol:
/* This is valid to omit the http:/https: protocol.
In that case, browser should automatically append
protocol used by the parent page */
var scripts = [
'//testdomain.test/script1.js',
'//testdomain.test/script2.js',
'//testdomain.test/script3.js'
];
The thing is, programatically created iframes have protocol about: (or javascript:, depending on how you create them). I still can't explain why the first script was loading or why the other two scripts were not showing up in the network tab at all, but I guess it's not very important.
The solution: either explicitly use https:// or programatically append protocol using something like the following code:
function appendSchema(win, url) {
if (url.startsWith('//')) {
var protocol = 'https:';
try {
var wPrev = undefined;
var wCur = win;
while (wPrev != wCur) {
console.log(wCur.location.protocol);
if (wCur.location.protocol.startsWith("http")) {
protocol = wCur.location.protocol;
break;
}
wPrev = wCur;
wCur = wCur.parent;
}
} catch (e) {
/* We cannot get protocol of a cross-site iframe.
* So in case we are inside cross-site iframe, and
* there are no http/https iframes before it,
* we will just use https: */
}
return protocol + url;
}
return url;
}
I've been successful using a simpler method than what the OP proposes in the self-answer. I produce the URLs using:
new URL(scriptURL, window.location.href).toString();
where scriptURL is the URL that needs to be fixed to get a proper protocol and window is the parent of the iframe element that holds the scripts. This can take care of scenarios that differ from the OPs example URLs: like relative URLs (../foo.js) or absolute URLs that don't start with a host (/foo.js). The above code is sufficient in my case.
If I were to replicate the search through the window hierarchy that the OP used, I'd probably do something like the following. This is TypeScript code. Strip out the type annotations to get plain JavaScript.
function url(win: Window, path: string): string {
// We search up the window hierarchy for the first window which uses
// a protocol that starts with "http".
while (true) {
if (win.location.protocol.startsWith("http")) {
// Interpret the path relative to that window's href. So the path
// will acquire the protocol used by the window. And the less we
// specify in `path`, the more it gets from the window. For
// instance, if path is "/foo.js", then the host name will also be
// acquired from the window's location.
return new URL(path, win.location.href).toString();
}
// We searched all the way to the top and found nothing useful.
if (win === win.parent) {
break;
}
win = win.parent;
}
// I've got a big problem on my hands if there's nothing that works.
throw new Error("cannot normalize the URL");
}
I don't have a default return value if the window chain yield nothings useful because that would indicate a much larger issue than the issue of producing URLs. There'd be something wrong elsewhere in my setup.
what I need
I need to hide js code in view source
js code
function unloadJS(scriptName) {
var head = document.getElementsByTagName('head').item(0);
var js = document.getElementById(scriptName);
js.parentNode.removeChild(js);
}
function unloadAllJS() {
var jsArray = new Array();
jsArray = document.getElementsByTagName('script');
for (i = 0; i < jsArray.length; i++){
if (jsArray[i].id){
unloadJS(jsArray[i].id)
}else{
jsArray[i].parentNode.removeChild(jsArray[i]);
}
}
}
var page_count = {{count()}};
if (page_count == 4)
{
dataLayer.push({'event':'mobilePromo-android'});
}
$(document).ready(function()
{
var page_count = {{count()}};
var height= $(window).height();
if (page_count == 4 )
{
$.ajax({
type: "GET",
url: "http://times.com/mobilepopuptracker?from=android",
});
$('body').html('<div class="row flush aligncenter popbx" style="height:'+height+'px"><div class="12u">');
}
else
{
}
});
function redirect()
{
var a=$(location).attr('href');
window.location.href=a;
}
</script>
Problem
I Need to hide js code in view source.
Debug
i have reffred the link find solution on http://www.sitepoint.com/hide-jquery-source-code/.
though code is still viewed.
any suggestion are most welcome.
though we know we cannot stop viewing of js in view source but still there must be some trick.
Use the online Google Closure Compiler service, it will make your code almost unreadable by doing things like renaming variables and function names. For example:
Raw JS
function toggleDisplay(el){
if (!el) return;
el.style.display = (el.style.display==='none') ? 'block' : 'none';
}
Closure Compiled
function toggleDisplay(a){a&&(a.style.display="none"===a.style.display?"block":"none")};
JavaScript Beautified
function toggleDisplay(a){
a&&(a.style.display="none"===a.style.display?"block":"none")
};
In doing so it also reduces the size of your script, helping to boost the loading time of your webpage.
You can still read the script, but its harder to understand and can get really complex when using things like JavaScript Closures.
You can't truly hide your js code. You can obfuscate it (i.e. make it difficult to read), but unlike PHP or Perl - which is processed on the server side - JS runs in the client's browser itself. Therefore, the client always has a copy of it, and can view that source at any time.
Well I am unable to lazy load images for some reason. Here is the waterfall view of the tested site
Apparently I am using two lazy load scripts with lazy load script 1 which works but kills the lightbox plugin and also requires lots of tweaking using data-src and src and class="lazy-load" attributes. which I am using for non post related images.
But the main problem lies in the second script which requires Jquery but doesn't require any tweaking with the images. The script is called stalactite (via Github) which I am using like this
<script charset='utf-8' src='http://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js' type='text/javascript' />
<script href='http://googledrive.com/host/0B2xMFcMT-eLiV1owdlBMeklGc2M' type='text/javascript' />
<script type='text/javascript'>
$( 'body').stalactite({
loader: '<img/>' // The contents of the loader. Defaults to a dataURL animated gif.
});
</script>
You can find the link of the stalactite script in the above code and here is the documentation.
I don't know why it doesn't work ! Or am I executing it wrongly.
A solution to the problem will be very helpful. Many thanks in advance.
If you are tired of trying to use lazy load libraries and haven't managed to make all of it work, I can suggest you to create lazy load script on your own, or you can take a look at this code below.
By only using jQuery and without needing any other library, you can use this script to achieve the lazy load (I modified the codes from the original one that I used at work):
var doLazyLoad = true;
var lazyLoadCounter = 0;
var lazyLoadMax = 2; // Maximum number of lazy load done
// Button to indicate lazy load is loading,
// or when lazy load has reached its maximum number,
// this button load data manually.
// You can replace this with something like gif loading animation.
var $btnLoadMore = $("#btn-lazy-load-more");
// I use AJAX function to get the data on lazy load
var ajaxFn = function (enableScrollAnim = true) {
var loadingStr = 'Loading...',
idleStr = 'Load more',
ajaxUrl = 'http://www.example.com/posts',
ajaxHeaders = {'HTTP_X_REQUESTED_WITH': 'XMLHttpRequest'},
ajaxData = {
start: $('.posts-wrapper .post').length
};
$btnLoadMore.text(loadingStr); // You can disable the button to prevent manual loading
return $.ajax({
url: ajaxUrl,
type: 'GET',
dataType: 'json',
data: ajaxData,
headers: ajaxHeaders,
// On success AJAX, append newly loaded data to lazy load container.
// Here in my example, the GET request returns data.view i.e. the content, and data.total i.e. total number of posts
success: function (data) {
var $newLoadedPosts = $(data.view),
nlsMarginBottom;
$('.posts-wrapper').append($newLoadedPosts);
$newLoadedPosts.css('display', 'none').fadeIn();
// Animate auto scroll to newly loaded content
if (enableScrollAnim) {
$('html, body').animate({
scrollTop: $newLoadedPosts.first().offset().top
});
}
if ($('.posts-wrapper .post').length < data.total) {
$btnLoadMore.text(idleStr); // If you disable the button, enable the button again here
} else {
// Remove the button when there's no more content to load.
// Determined by data.total
$btnLoadMore.remove();
}
},
error: function () {
$btnLoadMore.text(idleStr); // If you disable the button, enable the button again here
}
});
};
// Do the lazy load here
if ($btnLoadMore.length) {
$(window).scroll(function () {
var scrollOffset = (($btnLoadMore.offset().top - $(window).height()) + $btnLoadMore.height()) + 100;
var hasReachedOffset = $(window).scrollTop() >= scrollOffset;
var isLmsBtnExist = $btnLoadMore.length;
if (hasReachedOffset && lazyLoadCounter < lazyLoadMax && doLazyLoad && isLmsBtnExist) {
doLazyLoad = false;
ajaxFn(false).always(function () {
doLazyLoad = true;
lazyLoadCounter++;
});
}
});
}
$btnLoadMore.click(ajaxFn);
And here is the GIF demo image of my working code.
If you need any further explanation, just comment this answer and I will try to help you.
So I am developing a chrome extension right now in order to get introduced to the world of web development. I have run into a issue which I can't seem to get my head wrapped around. Currently, my background.js gets all the open windows along with the open tabs in each of them using:
function getAllOpenWindows(winData) {
var tabs = [];
for (var i in winData) {
/*if (winData[i].focused === true) {*/
var winTabs = winData[i].tabs;
var totTabs = winTabs.length;
for (var j=0; j<totTabs;j++) {
tabs.push(winTabs[j].url);
}
/*}*/
}
console.log(tabs);
}
which was actually posted by bpatel here. Now as you can see the commented line, it allows me to decide if the tabs are taken from just the current focused window or all the windows. My issue is that how exactly can I change this setting dynamically once the extension has been loaded into chrome and is being used actively? So if a user goes into options and says they want only all the windows I would be able pass a message to my background.js to say "hey use the all windows function and not the current focused window". I understand that 2 seperate functions should ideally be used here, this is just a sample on how it would be done. Thanks a ton!
You can use localstorage to save any user settings.
The options page and the background page share the same localstorage, so you can update the setting from options page and access the value from background page.
options.html
<input type="checkbox" id="windowType" value="All">Check all windows</input>
<input type="button" id="saveSettings" value="Save">Save</input>
options.js
document.getElementById("saveSettings").onclick = save_settings;
function save_settings()
{
var checkAll = document.getElementById("windowType").checked;
localStorage.setItem("check_all_windows",checkAll);
}
You can use a similar function to update the value of the checkbox with the current value, when the options page loads.
background.js
function getAllOpenWindows(winData) {
var tabs = [];
for (var i in winData) {
var checkAll = (localStorage.getItem("check_all_windows") == "true");
if (checkAll || winData[i].focused === true) {
var winTabs = winData[i].tabs;
var totTabs = winTabs.length;
for (var j=0; j<totTabs;j++) {
tabs.push(winTabs[j].url);
}
}
}
console.log(tabs);
}
In background.js, you can get the value of the same key from localStorage and check if it is set to true or false. Remember that the localStorage will store values as strings so you need to compare it with the proper strings - if("false") will evaluate to true.