Export HAR without the Toolbox being open

[janodvarko]

It should be possible to export HAR without the Toolbox being open. This would nicely simplify HAR export automation.

Honza

[janodvarko]

Asking here:
https://groups.google.com/forum/#!topic/mozilla.dev.developer-tools/bYuBECwXvHU

Honza

[soulgalore]

thanks looks promising! :)

[JosephCastro]

Please!

[janodvarko]

HAR API are not exposed to new tabs (about:newtab) in case e10s is on.
Caused by: https://bugzilla.mozilla.org/show_bug.cgi?id=1068400

The client (target) isn't firing "navigate" (neither onTabNavigated) event when about:newtab tab is navigated to another location. There is only "close". So, there is no way how to expose HAR API to the new loaded page.

---

@soulgalore @JosephCastro: The problem is only related to e10s, where the feature works only on the tab opened by default after Firefox launches (or tabs restored by the session manager).

What is actually your scenario? Are you loading pages directly in the default browser tab or opening other tabs as well? How typical scenario looks like?

Honza

[soulgalore]

The typical use case for us: We start the browser, load the URL directly in the default browser tab (we never open other tabs), collect some metrics using javascript and then close the browser.

Peter

[janodvarko]

There is a new preference: extensions.netmonitor.har.autoConnect (set to false by default)
If you set it to true, HAR object should be available on every page by default.

There is an event 'har-api-ready' sent to the content window. You might want to handle it to know since when the HAR object is available. The HAR object isn't available immediately after a browser tab is opened, but it's there till you close the tab. So, if you navigate/refresh the tab the HAR object is there all the time.

There is limitation if e10s is on. New tabs opened through about:newtab (i.e. clicking on the + button in the tab bar and consequently load the content) don't have the HAR object. However if you open a new tab through a link (Open In New Tab) it should work. The issue will be gone when https://bugzilla.mozilla.org/show_bug.cgi?id=1068400 is fixed.

I need feedback now.
Do you want me to generate xpi for you?

Honza

[soulgalore]

Wow sounds great. If you could generate an xpi I can test it asap.

[janodvarko]

http://janodvarko.cz/temp/har/harexporttrigger-0.5.0-beta.7.11.xpi

[soulgalore]

Thanks! Tested but I couldn't get it to work, maybe I do something wrong? First: I've got a test I use where I push the F12 using Selenium, it worked in the old version but when I only switched to the new xpi (didn't changed anything else), it failed (meaning no HAR object), is that expected? If I switch back to the old xpi it works.

[janodvarko]

Do you see any errors in the Browser Console? (Ctrl+Shift+J)?

[soulgalore]

Have everything automated so it's hard to see, will look into it tomorrow. Did a quick test manually and then your test page worked for me, so it could be something on my side, but I need some time to go through it.

[janodvarko]

Sure, thanks for testing!

[soulgalore]

ok, should the new version work in FF 42? When I test it now (I needed to clean my environment to get everything ok), I've set the following:

But I don't get it to work at all on the test page when I click on HAR export:

Or could I have missed a config?

[janodvarko]

Ah, it was a compatibility issue with Fx 42 (I didn't test it). Here is another fixed version:
http://janodvarko.cz/temp/har/harexporttrigger-0.5.0-beta.7.11.1.xpi
(your config is just fine)

Does this version work for you?

Honza

[soulgalore]

YES it works now, super! Works both testing manually and automated. Thanks, this is super cool.

[janodvarko]

Excellent, thanks for verification.

Honza