Render a page through controller

controller.rb

def comment
	@comment = Spree::Post.new(post_params)
	@comment.attributes = {user_id: current_spree_user.id}
	if @comment.save
		render json: {
			success: true,
			comment: render_to_string((@comment.parent_id.blank? ? 'spree/shared/_previous_comments' : 'spree/shared/_comment_line_item'), :layout => false, :locals => { :comment => @comment })
		}
	else
		render json: {
			success: false,
			errors: @comment.errors.full_messages.join(", ")
		}
	end
end