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How can I run a script in another (newly-opened) tab?

I am trying to run a script in a new tab. The code I use is this:
$ = jQuery;
function openAndPush(url, id) {
var win = window.open('https://example.com' + url + '?view=map');
var element = $('<script type="text/javascript">console.log("Starting magic...");var region_id='+id+';$=jQuery;var p=$(\'div["se:map:paths"]\').attr(\'se:map:paths\');if(p){console.log("Found! pushing..."); $.get(\'https://localhost:9443/addPolygon\', {id: region_id, polygon: p}, function(){console.log("Done!")})}else{console.log("Not found!");}</script>').get(0);
setTimeout(function(){ win.document.body.appendChild(element);
console.log('New script appended!') }, 10000);
}
Considering the following:
I was inspired in this answer, but used jQuery instead.
I run this code in an inspector/console, from another page in https://example.com (yes, the actual domain is not example.com - but the target url is always in the same domain with respect to the original tab) to avoid CORS errors.
When I run the function (say, openAndPush('/target', 1)) and then inspect the code in another inspector, one for the new window, the console message Starting magic... is not shown (I wait the 10 seconds and perhaps more). However the new DOM element (this script I am creating) is shown in the Elements tab (and, in the first console/inspector, I can see the New script appended! message).
(In both cases jQuery is present, but not occupying the $ identifier, which seems to be undefined - so I manually occupy it)
What I conclude is that my script is not being executed in the new window.
What am I missing? How can I ensure the code is being executed?

Instead of embedding script element in the document, do this.
wrap the code that you want to run in another tab, into a function.
bind that wrapped function to the new tab's window
Call that function
Here's the code that I ran in my console and it worked for me i.e another tab was opened and alert was displayed.
function openAndPush(url, id) {
var win = window.open('https://www.google.com');
win.test = function () {
win.alert("Starting magic...");
}
win.test();
setTimeout(function () {
win.document.body.appendChild(element);
console.log('New script appended!')
}, 10000);
}

Found that my error consisted on the origin document being referenced when creating a new script node, instead of the target document (i.e. win.document). What I needed is to change the code to reference the new document and create the node directly, no jQuery in the middle at that point. So I changed my code like this:
function openAndPush(url, id) {
var win = window.open('https://streeteasy.com' + url + '?view=map');
var element = win.document.createElement('script');
element.type='text/javascript';
element.innerHTML = 'console.log("Starting magic...");var region_id='+id+';$=jQuery;var p=$(\'div[se\\\\:map\\\\:paths]\').attr(\'se:map:paths\');if(p){console.log("Found! pushing..."); $.get(\'https://localhost:9443/addPolygon\', {id: region_id, polygon: p}, function(){console.log("Done!")})}else{console.log("Not found! searched in: ", document);}'
setTimeout(function(){ win.document.body.appendChild(element); console.log('New script appended!') }, 10000);
}
With this code something is essentially happening: The JS code is being parsed (and its node created) in the context of the new document. Older alternatives involved the origin console (since the origin document was implicitly referenced).

It's bad practice to send scripts to another webpage. You can pass some query params using a complicated URL and handle it by a source code from another webpage, it's much better:
function doMagicAtUrlByRegionId (url, regionId) {
window.open(`https://example.com${url}?view=map&magic=true&region_id=${regionId}`);
}

Force iframe to (re)load document when only src hash changes

I have an iframe that's supposed to load different modules of a web application.
When the user clicks a navigation menu in the top window, it's passes a new url to the iframe. The trouble is, the new url doesn't actually point to a new page, it only uses a changed hash.
i.e.:
User clicks "dashboard", iframe src set to application.html#/dashboard
User clicks "history", iframe src set to application.html#/history
This means that the iframe does not actually load the src url again because hash changes don't require it to. The application inside the iframe is an angular app which loads the required modules dynamically using requireJS. We need this functionality to remain.
I need to force the frame source to load again even though only the hash changed. It's possible that I instead find a way to rewrite our angular app to dynamically unload/load the modules on push state events but that introduces several layers of issues for the app, plus some IE trouble.
I've tried:
Setting iframe src and calling it's location.reload, but that reloads the originally loaded url
Setting the iframe location.href/hash and calling reload, same issue
Blanking the src attribute and then setting the new url - no effect
The only solution I can find is to set the src to a blank screen, then onload set it to the new url:
var appIFrame = document.getElementById('appIFrame');
appIFrame.src = 'about:blank';
appIFrame.onload = function(){
appIFrame.src = '// set the real source here';
appIFrame.onload = false;
}
This works, yet it seems inefficient because there's an extra step.

Maybe add a dynamic GET parameter – f.e. the current timestamp, which you can get from the JavaScript Date object – to the iframe URL.
Instead of assigning application.html#/dashboard as src value, assign application.html?1234567890#/dashboard from your outside page (with 1234567890 replaced by the current timestamp, obviously).

I don't have a specific answer for you. However, the following script may proved useful (I wrote this about a year or so ago). The following script deals with re-adjusting iframe height when the document changes. This script was tested cross-browser. It does deal with the issues you're experience but indirectly. There is a lot of commenting with the Gist:
https://gist.github.com/say2joe/4694780

Here my solution (based on this stackoverflow answer):
var $ = function(id) { return document.getElementById(id); };
var hashChangeDetector = function(frame, callback) {
var frameWindow = frame.contentWindow || frame.contentDocument;
// 'old' browser
if (! "onhashchange" in window) {
var detecter = function(callback) {
var previousHash = frameWindow.location.hash;
window.setTimeout(function() {
if (frameWindow.location.hash != previousHash) {
previousHash = frameWindow.location.hash;
callback(previousHash);
}
}, 100);
};
}
else // modern browser ?
{
var detecter = function(callback) {
frameWindow.onhashchange = function () {
callback(frameWindow.location.hash);
}
};
}
detecter(callback);
};
hashChangeDetector($('myframe'), function(hash) {
alert ('detecting hash change: ' + hash);
});
You can test this here: http://paulrad.com/stackoverflow/iframe-hash-detection.html

Injecting Javascript to Iframe

I am making a live editor for my website. I have the CSS and HTML parts down, only issue is the JS part now. Here is a snippet of the code
var frame = $('#preview_content'),
contents = frame.contents(),
body = contents.find('body');
csstag = contents.find('head').append('<style></style>').children('style');
java = contents.find('head').append('<script><\/script>').children('script');//Issues here
$('.area_content_box').focus(function() {
var $this = $(this);
var check = $this.attr('id');
$this.keyup(function() {
if (check === "html_process"){
body.html($this.val());
} else if(check === "css_process") {
csstag.text($this.val());
} else if (check === "java_process"){
java.text( $this.val() );
}
});
});
Problem is it is not injecting script tags in the iframes body nor the head when ever I try this. I've read up on injecting and some issues containing the ending script tag. I need to figure out how to inject script tags, really want them in the head but if it is easier in the body that is fine.
jfriend00 - I will be focusing on making this vanilla, if you think I should honestly.
So any words of advice on how to go about making my editor work correctly with the injecting JS?

These two lines of code look like they could have problems:
csstag = contents.find('head').append('<style></style>').children('style');
java = contents.find('head').append('<script><\/script>').children('script');//Issues here
It seems like it would be much better to create the style tag and remember that DOM element.
var iframe = document.getElementById("preview_content");
var iframewindow = iframe.contentWindow || iframe.contentDocument.defaultView;
var doc = iframewindow.document;
var csstag = doc.createElement("style");
var scripttag = doc.createElement("script");
var head = doc.getElementsByTagName("head")[0];
head.appendChild.cssTag;
head.appendChild.scriptTag;
$('.area_content_box').focus(function() {
var $this = $(this);
var check = this.id;
$this.keyup(function() {
if (check === "html_process") {\
// I would expect this to work
doc.body.html($this.val());
} else if(check === "css_process") {
// I don't know if you can just replace CSS text like this
// or if you have to physically remove the previous style tag
// and then insert a new one
csstag.text($this.val());
} else if (check === "java_process"){
// this is unlikely to work
// you probably have to create and insert a new script tag each time
java.text( $this.val() );
}
});
});
This should work for the body HTML and it may work for the CSS text into the style tag.
I do not believe it will work for the javascript as you can't change a script by assigning text to the tag the way you are. Once a script has been parsed, it's in the javascript namespace.
There is no public API I'm aware of for removing previously defined and interpreted scripts. You can redefine global symbols with subsequent scripts, but not remove previous scripts or their effects.
If this were my code, I'd remove the previous style tag, create a new one, set the text on it before it was inserted in the DOM and then insert it in the DOM.
If you're not going to do it that way, then you'll have to test to see if this concept of setting .text() on an already inserted (and parsed) style tag works or not in all relevant browsers.
For the script tag, I'm pretty sure you'll have to create a new script tag and reinsert it, but there's no way to get rid of older code that has already been parsed other than redefining global symbols. If you really wanted to start fresh on the code, you'd have to create a new iframe object from scratch.
There are other issues with this too. You're installing a .keyup() event handler every time the .area_content_box gets focus which could easily end up with many of the event handlers installed, all getting called and all trying to do the same work.

Ordered JavaScript File Loading

I need to dynamically load several JavaScript file assets in a very specific order after a page has loaded. I'm trying to use onload, but this seems to fire before the asset has fully loaded. How should I adjust the below script to fire a proper callback to load the next script?
Note: Only needs to work in the latest Chrome, Firefox, Safari, and IE9.
function loadAssets() {
// Setup script
var scriptJS = document.createElement('script');
scriptJS.type = 'text/javascript';
scriptJS.src = objectUrl;
scriptJS.onload = loadAssetsNext();
// Begin insertion
var headerJS = document.getElementsByTagName('HEAD');
headerJS[0].appendChild(scriptJS);
},
function loadAssetsNext() {
// Increment object counter
objectsCount++;
// Test to see if you should call another item
if ((objectsCount) < objects.length) {
// Setup script
var scriptJS = document.createElement('script');
scriptJS.type = 'text/javascript';
scriptJS.src = nextObjectUrl;
// Declare callback to fire after script has fully loaded
scriptJS.onload = loadAssetsNext();
// Begin insertion
var headerJS = document.getElementsByTagName('HEAD');
headerJS[0].appendChild(scriptJS);
}
}
What I need is something like scriptJS.fullyLoaded = doStuff. Have no clue where to go from here though.
PS: jQuery is not an option or another library. You should be able to do this by slightly modifying the above script.

The reason your onload event is firing immediately is that you are calling it, not assigning it.
scriptJS.onload = loadAssetsNext();
This just assigns the returned value from the call to loadAssetsNext to the property onload of the scriptJS object. What you are intending to do is:
scriptJS.onload = loadAssetsNext;
That sets the onload handler to be the loadAssests function. This should take care of your issues.

I think the problem is that your scriptJS.onload = loadAssetsNext(); is placed before headerJS[0].appendChild(scriptJS);
That means that your scripts would load and get appended to the page like this:
load script 1
load script 2
load script 3
...
append script 3
append script 2
append script 1
So I think you should just reorder your script a little bit.

How to inject a JavaScript function to all web page using Firefox extension

I am developing a Firefox addon. What I want to do is to inject a custom JavaScript function.
i.e.
function foo() {..}
So all the pages can call the foo without define it first.
I have look from other answer such as: http://groups.google.com/group/greasemonkey-users/browse_thread/thread/3d82a2e7322c3fce
But it requires modification on the web page. What if perhaps I want to inject the function foo into Google.com? Is it possible to do so?
I can do it with a userscript, but I want to use the extension approach if possible.

The first thing I thought when reading your question was "this looks like a scam". What are you trying to achieve?
Anyway, here's a Jetpack (Add-on builder) add-on that injects a script in every page loaded:
main.js:
const self = require("self"),
page_mod = require("page-mod");
exports.main = function() {
page_mod.PageMod({
include: "*",
contentScriptWhen: "ready",
contentScriptFile: self.data.url("inject.js")
});
};
inject.js:
unsafeWindow.foo = function() {
alert('hi');
}
unsafeWindow.foo();

What if you make a simple href with javascript function on the page.
Like bookmarklets work.
Here is a sample code :
function(scriptUrl) {
var newScript = document.createElement('script');
// the Math.random() part is for avoiding the cache
newScript.src = scriptUrl + '?dummy=' + Math.random();
// append the new script to the dom
document.body.appendChild(newScript);
// execute your newly available function
window.foo();
}('[url of your online script]')
To use it, put your script's url.
It must be only one line of code, url formated, but for code readability I've formated it.
I've never developed a Firefox extension, but for javascript injection that's how I would roll.
Hope it helped.

You can use Sandbox
// Define DOMContentLoaded event listener in the overlay.js
document.getElementById("appcontent").addEventListener("DOMContentLoaded", function(evt) {
if (!evt.originalTarget instanceof HTMLDocument) {
return;
}
var view = evt.originalTarget.defaultView;
if (!view) {
return;
}
var sandbox = new Components.utils.Sandbox(view);
sandbox.unsafeWindow = view.window.wrappedJSObject;
sandbox.window = view.window;
sandbox.document = sandbox.window.document;
sandbox.__proto__ = sandbox.window;
// Eval your JS in the sandbox
Components.utils.evalInSandbox("function foo() {..}", sandbox);
}, false);