Undefined method 'visible_to' - Simple Rails website - ruby-on-rails

Question

I'm in the process of creating a very simple wiki based website where users can upgrade and downgrade their account. One of the perks of being a 'premium' member is the ability to create private wikis.
The issue I'm having is to do with this piece of code in my wikis_controller.rb:
def index
#wiki = Wiki.visible_to(current_user)
#wikis = policy_scope(Wiki)
end
When the code is written like that, I get an error message saying 'undefined method 'visible_to'. But, if I comment out the first line in that method so that it looks like this:
def index
##wiki = Wiki.visible_to(current_user)
#wikis = policy_scope(Wiki)
end
the user can see the wiki index, but they cannot see their private wikis.
Any ideas where I am going wrong? For reference, here is my wiki_policy.rb:
class WikiPolicy < ApplicationPolicy
attr_reader :user, :record
def initialize(user, record)
#user = user
#record = record
end
def update?
user.present?
end
class Scope
attr_reader :user, :scope
def initialize(user, scope)
#user = user
#scope = scope
end
def resolve
wikis = []
if user.role == 'admin'
wikis = scope.all # if the user is an admin, show them all the wikis
elsif user.role == 'premium'
all_wikis = scope.all
all_wikis.each do |wiki|
if !wiki.private? || wiki.user == user || wiki.users.include?(user)
wikis << wiki # if the user is premium, only show them public wikis, or that private wikis they created, or private wikis they are a collaborator on
end
end
else # this is the lowly standard user
all_wikis = scope.all
wikis = []
all_wikis.each do |wiki|
if !wiki.private? || wiki.users.include?(user)
wikis << wiki # only show standard users public wikis and private wikis they are a collaborator on
end
end
end
wikis # return the wikis array we've built up
end
end
end
and here is my application_policy.rb:
class ApplicationPolicy
attr_reader :user, :record
def initialize(user, record)
#user = user
#record = record
end
def index?
end
def show?
if user.standard?
true
else
false
end
end
def downgrade?
if user.premium?
true
else
false
end
end
def create?
if user.present?
true
else
false
end
end
def new?
create?
end
def update?
user.present?
end
def edit?
update?
end
def destroy?
if user.present? && user.admin? #|| record.user == user)
true
else
false
end
end
def scope
Pundit.policy_scope!(user, record.class)
end
class Scope
attr_reader :user, :scope
def initialize(user, scope)
#user = user
#scope = scope
end
def resolve
scope
end
end
end
Many Thanks.

Answer 1

But even when I do add a 'visible_to' method to Wiki controller, I still pick up the same error message.
Without seeing your code I can't be certain but I am 95% sure your problem is that you're defining an instance method when you mean to define a class method.
You are probably doing this:
class Wiki
# instance method
def visible_to test
puts test
end
end
Which would allow you to call the function like instance method:
irb(main):018:0> Wiki.new.visible_to "hello world"
# hello world
irb(main):007:0> Wiki.visible_to "hello world"
# NoMethodError: undefined method `visible_to' for Wiki:Class
But since you are actually calling the function like a class method:
Wiki.visible_to(current_user)
You need to define your method like this:
class Wiki
# class method
def self.visible_to test
puts test
end
end
Now you can call the class method:
irb(main):024:0> Wiki.visible_to "hello world"
# hello world
irb(main):007:0> Wiki.new.visible_to "hello world"
# NoMethodError: undefined method `visible_to' for #<Wiki:0x00000001d16a68>
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