Deprecate string based action handling

[mehulkar]

We should deprecate all forms of string based actions. This includes:

• {{action "foo"}}
• (action 'foo')
• this.send('foo') (as discussed in Deprecate send API #609)

[rwjblue]

Thanks @mehulkar! I added a few labels to clarify where this is at. I personally think it should be possible to start charting out what that RFC would look like...

[chriskrycho]

I was talking with team members around this same topic today, especially this.send. The only significant blocker for its removal I could think of is that it’s the normal and idiomatic way to trigger an action on a route from its controller, which is currently the only way to fully reload a route’s model (using Route.refresh). The only alternative I’m aware of is to look up the corresponding route using the container, e.g. getOwner(this).lookup('route:same-as-controller').refresh().

An obvious intermediate step there might be to support refreshing a route on the router service. That would need to be designed independently of this, but it’s the only thing I know of which actually requires this.send in idiomatic Ember today. That would also be a nice step along the path of removing places we still need controllers today, and in a direction well-aligned with current directions in Ember API design. (I think there’s actually an open issue for this somewhere but I can’t find it and am typing on mobile at the moment.)

cc. @gabrielcsapo @jackson-dean

[mehulkar]

FWIW, it's not required, per se. There are a few ways to do this without .send. None of them are good, but 🤷

• Set Route.refresh as a property on the controller in setupController
• Use lookup('route:${RouterService.currentRouteName}').refresh()
• Use ember-route-action-helper addon

[rwjblue]

It isn't immediately obvious that we need per-route .refresh functionality to me (though maybe folks could share good use cases), and if that is the case then I think a top level router service .refresh method might be all we need.

[mehulkar]

That would also be a nice step along the path of removing places we still need controllers today,

Also, for the record, my understanding from #574 (comment) is that the core team was not in favor of incremental progress towards removing controllers.

[chriskrycho]

Certainly every use care I’ve hit for refresh would be solved by a single method on the router service. I’d also be curious if others can supply scenarios where that’s insufficient!

Also, note that ember-route-action-helper is deprecated; it’s a persistent source of issues for us and getting off of it is one of our motivations in this space.

[rwjblue]

Also, for the record, my understanding from #574 (comment) is that the core team was not in favor of incremental progress towards removing controllers.

IMHO, this case is a bit different. A couple reasons:

• Deprecating .send actually simplifies the programming model for controllers as well as without them
• Adding .refresh to router service addresses a gap (again regardless of controllers). It is a place where the dream/intent of the router service falls down: that there is "one router" and that router:main (app/router.js) vs service:router are indistinguishable.

Deprecating small pieces of functionality that only affects controllers, just for the sake of deprecating them, is the thing that seems bad/wrong (at least to this core team member). Deprecating a conceptual unit (this issue is discussing {{action + this.send for both controllers and routes) in phases is a very different thing.

[chriskrycho]

FWIW, I second Rob’s take (as a non-Core-team member). I simply observed that this change—well-motivated already on its own—is a case where landing it also produces incremental progress toward a potential removal of controllers in the future, because there’s lower coupling and one fewer hard dependency on them. It’s a nice bonus from making the programming model more consistent, rather than the point.

[mehulkar]

Since #632 has been opened and only the details need to be worked out, I think this is good to close! Thanks @Gaurav0!