Any interest in adding a props accessor?

[bfitch]

First, thank you contributors and maintainers for this great library. I'm so glad there's a solid option for building component based UIs in ruby/rails.

My project has quite a few component classes that do nothing but set instance variables for templates from keyword arguments. For example:

class SearchFieldComponent < ViewComponent::Base
  def initialize(search_text:)
    @search_text = search_text
  end
end

and

class NotesLayoutComponent < ViewComponent::Base
  def initialize(notes:, note:, search_text:)
    @notes = notes
    @note = note
    @search_text = search_text
  end
end

I've found myself wanting a props accessor, so I can just generate my component class and focus on the template, without needing to add add boilerplate instance variables (like above).

If you can remember back a few years to React's class Components, they provided a similar API with this.props.

Assuming most view_component users are using keyword arguments instead of positional arguments, it would be nice to have something like this in search_field_component.html.erb:

<form>
  <input
    placeholder="Search"
    value="<%= props.search_text %>"
  />
</form>

I've already added this to my project:

class BaseComponent < ViewComponent::Base
  attr_reader :props

  def initialize(args)
    @props = OpenStruct.new(args)
  end
end

But, it would be nice, IMO, if that came "out of the box". Thanks for your consideration!

[jaredcwhite]

This is on the hacky side to be sure, but I recently tried this out:

class ApplicationComponent < ViewComponent::Base
  def set_props(&block)
    local_binding = block.binding
    local_binding.local_variables.each do |key|
      instance_variable_set :"@#{key}", local_binding.local_variable_get(key)
    end
    yield
  end
end

and then in a component subclass:

class ReadMoreComponent < ApplicationComponent
  def initialize(id:, url:)
    set_props {}
  end
end

or adding extra derived "props":

class PostComponent < ApplicationComponent
  def initialize(post:, show_source: true, hide_hide_toggle: false)
    set_props do
      @source = @post.source
    end
  end
end

That lets me make instance variables out of all keyword arguments automatically. (Magic!)

[joelhawksley]

I recently landed better compatibility with Dry::Initializer in the v4 branch: https://github.com/ViewComponent/view_component/pull/2332/files#diff-2bfab3db5cc1baf4c6d3ff6b19901926e3bdf4411ec685dac973e5fcff1c723bR17. Let me know what you think!