prevent multiple loading of the same template.

[guyklainer]

The issue is that the same template was loaded as mush as the directive was used.

My assumption is that the templateCache service didn't had a chance to save the template from the first fetch so he keep sending http requests each time.

solution:
save array of the promises and just if the template key is not in the array, fetch it.

[mgcrea]

I'd rather keep using the $templateCache, could you write an unit test to reproduce the issue? (Define a custom template, intercept the http, compile another directive, check that no http req is sent).

[guyklainer]

Its still using the $templateCache.
The only different is that the 'templates' object keeping the promise from the $http, so if there is one in this object, it will not call again to the $http.
The 'templates' object is just a pipe.

This fix should resolve this open issue:
#758

The solution he is using there is just a hack.

[vmlf01]

Since this is used in multiple places, maybe refactor it into a helper service?
Also, you should remove the element from templates once a template promise is resolved to cleanup.

[guyklainer]

yes,
this two was exactly my next steps..

[vmlf01]

Ah, sorry, looks like you could just keep the element in the templates array to avoid going into $q.when again.

Just saw similar usage yesterday from awesome $q presentation at ng-europe: http://youtu.be/33kl0iQByME?t=13m54s

[guyklainer]

Nice..
so just refactoring out to helper service... :)

[mgcrea]

I'm not sure you need an array/map to begin with, that's redundant to what $cacheFactory is doing. To me, the proper fix should be something like this:

return $q.when($templateCache.get(template) || $http.get(template).then(putTheResponseIntoTemplateCache))

[vmlf01]

The array is just for storing the promises, not the templates themselves, so if the second request is made before the first promise fulfills, it won't trigger the $http loading of the template, it just returns the previous stored promise, and when the original $http request finishes, all the pending requests will resolve.
It is worth checking the video, I think it explains it better.

[mgcrea]

Got it, indeed squashing requests is a good idea and that's not covered by $cacheFactory, should clearly live in a separate helper.

[mgcrea]

Finally implemented this without a separate helper as it would be a breaking change for any project requiring specific files of the build. Though it might be worth a refactor in the future.

[lopex]

The fetchPromises cache prevents client code from updating $templateCache manually and having the new template being used from now on

[mgcrea]

@lopex looks like this might be a bug, could you please open a new issue?