1029203 - Emulate being offline

Status: NEW

(DevTools :: Netmonitor, enhancement, P3)

Description

[Jeff Griffiths (:canuckistani) (:⚡︎)]

It would be useful to have a switch that completely emulates being offline, for the current tab. Chrome does this as part of their new network emulation feature.

Comment 1

[Mike Ratcliffe [:miker] [:mratcliffe] [:mikeratcliffe]]

There used to be an excellent addon that did this. Unfortunately it was Windows only and used it's own dll for the throttling service but maybe we could draw a little inspiration from it's implementation:
https://github.com/hkirsman/Firefox-Throttle/blob/master/src/components/FFThrWatcher.js#L71

Comment 2

[Jeff Griffiths (:canuckistani) (:⚡︎)]

Assigning P1 priority for some devedition-40 bugs. 

Filter on '148DD49E-D162-440B-AE28-E22632FC20AC'

Comment 3

[Alexandre Poirot [:ochameau]]

I think `Services.io.offline = false` would do something similar, but the issue is that it is global to the whole browser.
FxOS implemented something better and supports toggling just one app into offline mode:
  Services.io.setAppOffline()
  http://mxr.mozilla.org/mozilla-central/source/netwerk/base/nsIIOService.idl#169

I tried to fake an app on a tab and used this setAppOffline API, but it doesn't seem to work.

Anyway, this features allows us to have an idea how hard it would be to have a per-docshell offline state:
  http://mxr.mozilla.org/mozilla-central/ident?i=IsAppOffline
  http://mxr.mozilla.org/mozilla-central/ident?i=NS_IsAppOffline
i.e. quite significant work!

For example:
  http://mxr.mozilla.org/mozilla-central/source/netwerk/protocol/http/nsHttpChannel.cpp#2715

Comment 4

[Jeff Griffiths (:canuckistani) (:⚡︎)]

Adding difficulty=hard whiteboard - please adjust if you disagree but I suspect this is what Alex means.

Alex - if you have some time while you're thinking about this issue, can you file a platform bug to represent the platform changes we would need to set a tab in an offline state? Please cc me.

Comment 5

[Alexandre Poirot [:ochameau]]

Done, bug 1156659.

Comment 6

[Patrick Brosset <:pbro>]

Triaging. Not a P1 anymore according to our new triage process, and not being actively worked on (filter on CLIMBING SHOES).

Comment 7

[Patrick Brosset <:pbro>]

Hey Honza, I think this has been implemented in another bug, right? If so, can you close it as a duplicate please?

Comment 8

[Jan Honza Odvarko [:Honza] (always need-info? me)]

(In reply to Patrick Brosset <:pbro> from comment #7)
> Hey Honza, I think this has been implemented in another bug, right? If so,
> can you close it as a duplicate please?
I don't know about any new net feature that would implement this.
Also, the platform bug 1156659 is still open.

Note, that we recently implemented pause/resume (bug 1005755), but it's different thing.

Honza

Comment 9

[Jan Honza Odvarko [:Honza] (always need-info? me)]

Attachment: image.png

The offline option could be part of the Throttling drop down, as mentioned here:

https://mobile.twitter.com/nhoizey/status/1094871488707080192
https://pbs.twimg.com/media/DzHDz3QX0AALDPO.jpg

Honza

Comment 13

[Simon Pieters [:zcorpan]]

A request for this feature came up in my google alerts:
https://stackoverflow.com/questions/74805554/how-do-i-deactivate-the-internet-entirely-with-firefoxs-developer-tools

Comment 14

[Max Waterman]

If someone is going to implement this, please also consider adding an option to the CLI so the browser can be started in offline mode (if a --set-pref won't do the trick)