1569135 - --screenshot option in Firefox headless mode stopped working

Status: VERIFIED FIXED

(Firefox :: Headless, defect)

Description

[Pascal Chevrel (relman team) -> :pascalc]

Mozilla/5.0 (X11; Linux x86_64; rv:70.0) Gecko/20100101 Firefox/70.0 ID:20190725215157

STR:
1/ type firefox --screenshot https://mozilla.org in a terminal

ER:
A screenshot.png page is generated in the current folder

AR:
No screenshot generated.

This regression was reported by a user (guillermo) in IRC and I can reproduce the bug.

Comment 1

[Pascal Chevrel (relman team) -> :pascalc]

I quickly tested manually as I can't find how to use mozregression in headless mode, 68 is not affected but this is a 69 regression. marking as tracking for 69 and 70 as this is a functional regression of the headless mode.

Comment 2

[Pascal Chevrel (relman team) -> :pascalc]

mozregression --good 2019-05-25 --arg="--screenshot" --arg="https://mozilla.org" --arg="--headless"
16:34.99 INFO: Last good revision: d08d899e5431458f7c28ca66a13e3e95dff9c7c1
16:34.99 INFO: First bad revision: 2236a18eb0a91be02e72c22e370a6f5aa877f11e
16:34.99 INFO: Pushlog:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=d08d899e5431458f7c28ca66a13e3e95dff9c7c1&tochange=2236a18eb0a91be02e72c22e370a6f5aa877f11e

Regressed by bug 1560178 which was uplifted to beta, Gijs could you have a look please? Thanks!

Comment 3

[Ryan VanderMeulen [:RyanVM]]

Andrew, can you maybe take a look at this since Gijs is on PTO for the next couple weeks and we're running low on time for Fx69? Thanks!

Comment 4

[Andrew Swan [:aswan]]

It looks like --screenshot has always loaded the page to take a screenshot of in the parent process (the relevant code is basically the entire contents of browser/components/shell/HeadlessShell.jsm) so its no surprise that it was broken by bug 1560178.
My knowledge of the platform level here is shaky, the only way I would know how to approach this is to load a small document that contains a <browser remote="true"> and then load the actual content page inside that browser.
Leaving the needinfo for myself pending further research.

Comment 5

[Andrew Swan [:aswan]]

Okay, I think the approach from comment 4 is the only way to go.

Also this has a test but for some reason it is a chrome mochitest. The test copies the test profile preferences to create a profile to run firefox -screenshot but since this is a chrome mochitest, the new profile inherits among other things: browser.tabs.remote.autostart = false. So, we're testing the unsupported e10s-disabled configuration where of course content loads in the parent process are allowed. Yay.

Comment 6

[Andrew Swan [:aswan]]

Attachment: Bug 1569135 Fix --screenshot r=kmag

not ready for landing, putting this up to get feedback before polishing.
note that the automated test of this feature is still broken, bug 1570554
is on file for fixing it.

Comment 7

[Cristian Fogel [:cfogel]]

Clearing the regression-window-wanted tag based on comment 2.

Comment 8

[:Gijs (he/him)]

Thanks for looking at this, Andrew!

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b4678e759a18
Fix --screenshot r=kmag

Comment 10

[Cristian Brindusan [:cbrindusan]]

Backed out changeset b4678e759a18 (Bug 1569135) for mochitest failures at test_headless_screenshot.html.

Backout: https://hg.mozilla.org/integration/autoland/rev/b7f5d743d08b5df92c5b167eb7b03ded01250b7c

Push that started the failures: https://treeherder.mozilla.org/#/jobs?repo=autoland&resultStatus=pending%2Crunning%2Csuccess%2Ctestfailed%2Cbusted%2Cexception&revision=b4678e759a188230e3929f4f4874c967e1cabfd2&selectedJob=260398429

Failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=260398429&repo=autoland&lineNumber=4042

Comment 11

[Andrew Swan [:aswan]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=5b5b28975a0117a733824fd8198849566180808a

Comment 12

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4ee4a9ba5593
Fix --screenshot r=kmag

Comment 13

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/4ee4a9ba5593

Comment 14

[Andrew Swan [:aswan]]

Comment on attachment 9082157 [details]
Bug 1569135 Fix --screenshot r=kmag

Beta/Release Uplift Approval Request

• User impact if declined: Running firefox with the -screenshot command line argument will be broken
• Is this code covered by automated tests?: Yes
• Has the fix been verified in Nightly?: No
• Needs manual test from QE?: Yes
• If yes, steps to reproduce: See original bug
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): The only changes to shipping code are bundling a new jsm and modifying code that is only loaded/run when -screenshot is present in the command line arguments.
• String changes made/needed: none

Comment 15

[Ryan VanderMeulen [:RyanVM]]

Comment on attachment 9082157 [details]
Bug 1569135 Fix --screenshot r=kmag

Fixes a regression in 69 causing the --screenshot flag to be broken. Approved for 69.0b13.

Comment 16

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/releases/mozilla-beta/rev/f80d1353670b

Comment 17

[Florencia Di Ciocco, NI to vbalducci]

Attachment: Linux.png

Hi Andrew,

I've been trying to reproduce this bug but I have a problem. As you can see in my screenshot, I've installed version 69.0b12 to first try and reproduce this bug. When I run the command <./firefox -p> to execute FF, it does so without problems. As seen, it opens version 69.ob12. However, when I try to take the screenshot the console is trying to take the screenshot of version 68.0.1.

This way, I can't reproduce the bug nor verify if it's fixed since it always takes the screenshot of version 68.0.1, regardless of the version I've downloaded.
Is there a way around or is this a problem with firefox?
Best regards, Flor.

Comment 18

[Andrew Swan [:aswan]]

It looks like you just need to use ./firefox instead of firefox when running the tests with the -screenshot argument?

Comment 19

[Florencia Di Ciocco, NI to vbalducci]

Hi Andrew,

Thanks a lot for the help! I've been able to reproduce the bug on older versions and I've been able to take the screenshot on the latest nightly 70.0a1 (2019-08-16) (64-bit) and latest beta 69.0b13 (64-bit). Therefore, I've changed the status of the bug to verified fixed.

Best regards, Flor.

Comment 20

[Ryan VanderMeulen [:RyanVM]]

Comment on attachment 9082157 [details]
Bug 1569135 Fix --screenshot r=kmag

Per https://bugzilla.mozilla.org/show_bug.cgi?id=1560178#c34.

Comment 21

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-esr68/rev/e1691edfb301