Clean up get_endpoints

Clean up get_endpoints

get_endpoints was being called on every instance of service_add and not being garbage collected.  Moved it to on_database_changed and added gc around services being removed.

https://code.launchpad.net/~makyo/juju-gui/endpoints-once/+merge/137273

(do not edit description out of merge proposal)

[matthew.scott, 2012-11-30 17:36:07]

Please take a look.

[hazmat, 2012-11-30 21:17:40]

Missing a unit test.

Else looks good.

Merge with changes.

Thanks

https://codereview.appspot.com/6858099/diff/1/app/app.js
File app/app.js (right):

https://codereview.appspot.com/6858099/diff/1/app/app.js#newcode314
app/app.js:314: if (!Y.Lang.isValue(this.serviceEndpoints)) {
i'd suggest moving this to the initializer and dropping the conditional instead
of lazy value initialization.

https://codereview.appspot.com/6858099/diff/1/app/app.js#newcode323
app/app.js:323: return updateNeeded;
return is extraneous here

[matthew.scott, 2012-12-03 20:27:11]

Please take a look.

[bac, 2012-12-04 16:28:34]

Looks good but I've suggested a code simplification.  No need to re-review.

https://codereview.appspot.com/6858099/diff/5001/app/app.js
File app/app.js (right):

https://codereview.appspot.com/6858099/diff/5001/app/app.js#newcode325
app/app.js:325: 
.some() returns true or false so I think you could just do:

var updateNeeded = this.db.services.some(function(service) {
         return (self.serviceEndpoints[service.get('id')] === undefined)});

[matthew.scott, 2012-12-04 22:15:42]

*** Submitted:

Clean up get_endpoints

get_endpoints was being called on every instance of service_add and not being
garbage collected.  Moved it to on_database_changed and added gc around services
being removed.

R=
CC=
https://codereview.appspot.com/6858099