Re: Permission-hint? (was Re: [Bug 22214] How long do permissions persist?)

On 5/14/14 3:50 PM, Jim Barnett wrote:
> It is more user friendly for the app to prompt once for all the 
> cameras it needs.   On the other hand, if the app prompts multiple 
> times, the user can allow some and deny others, while in your second 
> example (app asks for both cameras) he cannot.

False causation. This was just a UA example, where I left out details 
[2]. As Harald points out it's entirely a UA design choice whether 
permission is given for a particular camera or for all cameras.

The app doesn't prompt. The UA prompts. Therefore the user's ability to 
"allow some and deny others" is fully at the discretion of the UA, 
regardless of how many times the app requests user-media. A UA could 
implement nothing but an all-or-nothing permission model and be compliant.

Firefox has camera-selection options [2] in permission prompts, but I 
left those out to focus on default behavior. I want to add to the 
default experience, not mandate removal of any user-options. So it's 
just more user friendly with no downside. ;-)

>   Is that just a matter of UI design?

Yes.

> Could the prompt list the cameras separately,

Sure:

Camera: Both (default) <--- new
            Front
            Back


UAs can already implement "both" (or "all" in generall) either all of 
the time or none of the time. I'm asking for hints to be able to default 
to it more intelligently.

> or do you have reasons not to want to do this?

Sure, but those are unchanged (our current camera selector looks pretty 
complicated).

> One option for asking for multiple cameras would be to hack/kluge an 
> extra argument into gUM that indicates that  the app will be asking 
> for more devices.   So the app could call gUM multiple times but the 
> user would be prompted only once the app indicated that it had made 
> its final request.  (The parameter could be something like 
> 'additionalRequest' with a default value of 'false'.  If gUM is called 
> with 'additionalRequest=true', the UA stores the description of the 
> desired device but waits to display the permissions prompt.)

Yes, if we cared about the difference between all cameras and "more than 
one camera but short of all". Otherwise I think what we're suggesting 
seems the same.

.: Jan-Ivar :

> On 5/14/2014 3:24 PM, Jan-Ivar Bruaroey wrote:
>> On 5/14/14 8:49 AM, Harald Alvestrand wrote:
>>>> On 5/30/13 9:48 AM, bugzilla@jessica.w3.org wrote:
>>>>> 4.  Suppose the app requests a camera and the user gives it permission to use
>>>>> all cameras.  The app initially uses only a single camera but later decides
>>>>> that it wants a different one.  Does it have to request permission again (given
>>>>> that the user granted permission for all cameras)?
>>> On 03/19/2014 03:34 PM, bugzilla@jessica.w3.org wrote:
>>>> I think it's an UA design choice whether permission is given for a 
>>>> particular
>>>> camera or for all cameras.
>>
>> I agree it is a UA design choice, but I could use some help avoiding 
>> "grant all".
>>
>> Specifically, I wish an app could hint that it might ask for more 
>> cameras later, to reduce dialog-fatigue.
>>
>> Problem case A (please ignore camera-selectors in permission-prompts 
>> here [1]):
>>
>>  1. User launches webapp Foo on their mobile.
>>  2. Mobile says "Foo wants to use your front camera. Allow/Deny -
>>     Remember my choice[x]"
>>  3. User touches "Allow", with "Remember my choice [x]" checked.
>>  4. User sees self and touches the "<->" back/front flip button that
>>     Foo has.
>>  5. It says "Foo wants to use your rear camera. Allow/Deny - Remember
>>     my choice[x]"
>>  6. User curses and touches "Allow" again, with "Remember my choice
>>     [x]" checked.
>>
>>
>> Given that Foo has a "flip" button (and is using constraints), it 
>> seems superior to ask the user for both cameras upfront here (B=both):
>>
>>  1. User launches webapp Foo on their mobile.
>>  2. Mobile says "Foo wants to use both of your cameras. Allow/Deny -
>>     Remember my choice[x]"
>>  3. User touches "Allow" with "Remember my choice [x]" checked.
>>  4. User sees self and pushes the "<->" back/front flip button that
>>     Foo has.
>>  5. User sees the Eiffel Tower.
>>
>>
>> Of course, we could always do B but it discourages "minimal access" 
>> apps. For example: "Foo wants to use your front camera. Allow/Deny?" 
>> is more comforting in a BossTalk app, if my boss doesn't know I'm in 
>> Paris.
>>
>> Here's one idea: We could put in a hint [2], like:
>>
>>     getUserMedia({ video: { askPermissionFor:"one"|"all" } }, 
>> success, failure);
>>
>> which UAs would be free to ignore.
>>
>> Or we could interpret a lack of constraints to mean "prefer 
>> grant-all" - which I'm considering - but it seems like an overload.
>>
>> Thoughts?
>>
>> .: Jan-Ivar :.
>>
>> [1] Firefox has a camera-selector in the permission prompt, but we're 
>> finding it's no panacea for not having good defaults.
>> [2] Requesting multiple cameras is clearly out-of-scope, and I don't 
>> want to talk about that.
>>
>
> -- 
> Jim Barnett
> Genesys