We observe last build on the repo in order to show the freshest build on
repo page. I moved it to router in order to keep such observers in the
same place, but this was not a wise move. To make it work properly
observer needs to be removed when moving to some other part (like
build's page). The problem is that deactivate function is not called
when we move to the other route in the same nesting. We have our own
'activate' function on repoController, which is better suited for
handling this task.
Previously we were checking if we should display an error message by
adding if statements in a template. This is not the best way to do
it, because it clutters a template and makes code harder to follow.
In this commit I move rendering error templates to the router. Code for
rendering error when there is no builds is not the best way to do it
either, but it can be improved when new router changes are merged to
Ember's master and a way Ember Data is handling promises is revised and
improved.
Till now, when switching between different views, we were switching
different bindings on repo controller. This was quite innefficient,
because then we needed to add bindings also from other controllers and
it's hard to manage such structure when we would like to add specialized
controllers (like LogController).
The new setup is more declarative, meaning that we do such things on the
router and set things on proper controllers. The only drawback is that
now we need to setup a few observers instead of bindings for "current"
views (ie. when viewing the newest repo or when viewing the last build
in current repo).
At this point it may not look like huge improvement, but it will open a
way to more refactorings.
Visibility.js provides a thin wrapper over page visibility API, which
allows to detect if page is currently visible by user. This allows us to
stop live updates when it's not needed. This is especially easy in case
of timers, because Visibility.js provides setInterval replacement, which
runs given code only when page is visible.
A lot of ❤️ for @tchack, who showed me visibility.js!
It seems that running Ember.run.later periodically can cause CPU usage
to increase over time. Such increase adds up to already increasing CPU
usage because of data amount growing.
This commit tries to mitigate the issue by using setTimeout instead
