Re: Single instance mode vs multiple instances in manifest spec

On 23/04/13 20:03, Jonas Sicking wrote:
> On Tue, Apr 23, 2013 at 1:22 AM, John Lyle <john.lyle@cs.ox.ac.uk> wrote:
>> A follow-up question for both Tizen and FirefoxOS systems -
>>
>> Can devices have more than one version of the same application installed at
>> the same time?  And can there be independent instances of each version
>> running?  E.g., can I have version 0.1 and version 0.2 of app://example.com
>> installed, and then run two instances of version 0.1 and two instances of
>> version 0.2 (making four total instance) at the same time?
> I think we should prohibit runtimes from allowing two versions to run
> at the same time. Two versions running at the same time is really hard
> for apps to support any time both instances are trying to interact
> with locally stored data, such as data stored in IndexedDB. You can
> easily end up with the two versions using different schemas and
> stomping on each other's data.

Thanks Jonas & Januz for your replies.  These were the answers I was 
expecting, thanks for the confirmation.

>
>> I'm trying to get the cardinality of entities right: for every installed
>> application there may be multiple runtime instances.  Every installed
>> application will have one origin.  But can two or more installed
>> applications (not instances) have the *same origin*?
> I don't see how this question relates the the above question,

It was a hypothetical edge case: If multiple versions of 
app://example.com could be installed on the same platform, then 
effective two different (albeit with the same name) applications would 
be given the same origin.  Based on your first answer, this particular 
case wont happen.

> but the
> answer is yes. Two hosted apps can come from the same origin. And
> if/when we support "real" origins for packaged apps, two packaged apps
> can come from the same origin, or a packaged app can come from the
> same origin as a hosted app.


OK. Do you expect that this working group will initially define a 
standard supporting multiple apps with the same origin?Or will we start 
with the one-app-per-origin approach and then update the document later on?

Best wishes,

John

Received on Wednesday, 24 April 2013 10:52:23 UTC