649615 - Page-Mod Content-Scripts loaded twice in some occasions

Status: RESOLVED FIXED

(Add-on SDK Graveyard :: General, defect, P1)

Description

[Nicolas Côté-Nolin]

User-Agent:       Mozilla/5.0 (X11; U; Linux x86_64; en-US) AppleWebKit/534.16 (KHTML, like Gecko) Chrome/10.0.648.151 Safari/534.16
Build Identifier: addon-sdk-1.0b4

In some specific occasions, the content-script of a page-mod is injected twice in a page. This happens when attaching the worker on the tabs.onReady event.

For this to happens, a precise timing where the tabs.onReady is fired but the page isn't totally loaded yet (firefox still shows the page as loading) needs to be respected.

Reproducible: Sometimes

Steps to Reproduce:
1. Go to a page where the load time is longer
2. Just before the page finish completely loading, change the adress in the url and go to another page.
Actual Results:  
From time to time (the timing issue makes it hard to reproduce), the content-scripts will be loaded twice.

Expected Results:  
The worker of the 1st loaded page should unattach.

Here some code :

main.js
tabs.on('ready', function(tab) {
  var worker = tab.attach({
    contentScriptFile: listContentScriptFiles,
    onMessage: function() { // not important }
  });
});

content-script:
console.log(document.domain);
// Some logic that takes some times
console.log(document.domain); // won't log the same domain 

FYI, I'm loading a long list of content-script, maybe it's one of the reason for this bug.

For test purpose, I've used mostly www.cyberpresse.ca as the 1st domain and localhost as the 2nd.

Comment 1

[Alexandre Poirot [:ochameau]]

Thanks for the report!

Yes I've implemented tab.attach that way. It will be attached once and be kept alive over all document loaded in the tab.
But it has been recently considered as a bug and is going to be changed.
A patch in bug 607601 is already in review and is going to unattach this worker at document unload.

So if you do:
window.documentaliste("load", function () {
  console.log(document.domain);
}, false)
Currently you will have a log message at each new document loaded.

But with patch mentioned before, you won't ever had a message because this worker is going to be destroyed at first document unload.

I let this bug open until you confirm me that bug 607601 patch fixed your problem.

Comment 2

[Alexandre Poirot [:ochameau]]

Nicolas: Can you confirm that your problem is solved in 1.0b5 release?
http://blog.mozilla.com/addons/2011/05/05/announcing-add-on-sdk-1-0b5/

Comment 3

[Nicolas Côté-Nolin]

I'll have a look. Right now, I'm having a little problem running my extension with 1.0b5 because I have mutliple 

TypeError: this._.ownerDocument.defaultView is null 

when opening new tabs. So I'll try to find what changes I need to make so my extensions work correctly.

Comment 4

[Alexandre Poirot [:ochameau]]

This error seems to come from RightJS:
https://github.com/rightjs/rightjs-core/blob/master/src/dom/element/styles.js#L69

We are working on content scripts sandboxes, there is some issues with js frameworks for the moment.

Comment 5

[Nicolas Côté-Nolin]

I've been trying to reproduce this bug with the 1.0b5 version of JetPack without any success, so this problem seems solved to me!