On Sep 10, 2009, at 12:55 PM, Darin Fisher wrote:
On Thu, Sep 10, 2009 at 12:32 PM, Maciej Stachowiak <[email protected]>
wrote:
On Sep 10, 2009, at 11:22 AM, Michael Nordman wrote:
On Wed, Sep 9, 2009 at 7:55 PM, Robert O'Callahan <[email protected]
> wrote:
On Thu, Sep 10, 2009 at 2:38 PM, Michael Nordman
<[email protected]> wrote:
If this feature existed, we likely would have used it for offline
Gmail to coordinate which instance of the app (page with gmail in
it) should be responsible for sync'ing the local database with the
mail service. In the absence of a feature like this, instead we
used the local database itself to register which page was the
'syncagent'. This involved periodically updating the db by the
syncagent, and periodic polling by the would be syncagents waiting
to possibly take over. Much ugliness.
var isSyncAgent = false;
window.acquireFlag("syncAgency", function() { isSyncAgent = true; });
Much nicer.
How do you deal with the user closing the syncagent while other app
instances remain open?
In our db polling world... that was why the syncagent periodically
updated the db... to say "still alive"... on close it would say
"i'm gone" and on ugly exit, the others would notice the lack of
"still alives" and fight about who was it next. A silly bunch of
complexity for something so simple.
In the acquireFlag world... wouldn't the page going away simply
relinquish the flag?
How would the pages that failed to acquire it before know that they
should try to acquire it again? Presumably they would still have to
poll (assuming the "tryLock" model).
Regards,
Maciej
In my proposed interace, you can wait asynchronously for the lock.
Just call acquireLock with a second parameter, a closure that runs
once you get the lock.
What if you don't want to wait asynchronously? My reading of this is
that you need two copies of the code, one that works synchronously,
but you still need to keep the asynchronous model to deal with an
inability to synchronously acquire the lock. What am I missing?
-Darin
--Oliver
