using rails helpers (link_to, for instance) within a component.

[fakeharxy]

First, hope this is the right place for specific technical queries, let me know if not.

Second, obligatory "noob" disclaimer.

That out the way, I'm trying to use various rails helpers, most notably a path helper, within a component, whilst creating a second, internal component.

Example:

BootstrapButtonComponent.new(href: reservation_assignment_path(reservation), variant: :success)

for instance.

This is hitting the "#controller cannot be used during initialization, as it depends on the view context that only exists once a ViewComponent is passed to the Rails render pipeline" error. Oddly it seems to work in the live environment (I think...) but not in my tests.

Is there a way to use the path helpers within a component, or is it simply not possible with the way they are built? Does the question even make sense?

Thanks,

[Spone]

Hi @fakeharxy can you copy the full component class?

[fakeharxy]

Hi @Spone, thanks for your help. We are calling the action components within the template, like so (this is slim)

  - action_components.each do |action_component|
     = render action_component

I haven't yet looked into Slots, but if they solve the problem, I'm interested!

[fakeharxy]

Yeah, if I try to use helpers, as you suggested above, I get the same message, but about helpers rather than controller

ViewComponent::Base::ViewContextCalledBeforeRenderError:
       `#helpers` cannot be used during initialization, as it depends on the view context that only exists once a ViewComponent is passed to the Rails render pipeline.

[fakeharxy]

I wonder if I could pass it through as a lambda and then call it within the BootstrapButtonComponent?

[Spone]

Here is how I would do it with slots (I removed all unrelated code for clarity). I haven't tested the code so it may need additional work :)

class StatePanel::KitReservationsStateRowComponent < ApplicationComponent
  renders_many :action_components, -> () do
    if Platform.sti_test_order_workflow.kit_reservation_scannable?(kit_reservation, user)
      BootstrapButtonComponent.new(text: translation_for(key: 'scan_kit'), href: kit_reservation_assignment_path(kit_reservation), variant: :success)
    else
      DisabledButtonComponent.new(text: translation_for(key: 'scan_kit'))
    end
  end

  # ...
end

Then in the component template:

- action_components.each do |action_component|
  = action_component

[fakeharxy]

This looks perfect! Thanks very much, I'll give this a shot.

[wakproductions]

I got here after receiving that error message about not being able to use before initialization. Found out it was because I was trying to access the URL helper within the component's initialize constructor. Fixed my issue by rearranging that code so that the helper gets called later.

[reeganviljoen]

you can also use before_render to get access to helpers before rendering