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Ruby

Posted by Andrew Stelmach
Andrew Stelmach
12,583 Points

Groupify NameError

After setting up Groupify as per the documentation, I launch my console and do:

user = User.new
group = Group.new
group.add user

This returns the following error:

NameError: uninitialized constant User::GroupMembership

I can't for the life of me work out this problem. You can check out Groupify's documentation on Github, and here are my models:

user.rb:

class User < ActiveRecord::Base
    authenticates_with_sorcery!

    validates :name, presence: true
    validates :password, length: { minimum: 4 }
    validates :password, confirmation: true
    validates :password_confirmation, presence: true

    validates :email, uniqueness: true

    has_many :testimonials
    has_many :materials

    groupify :group_member
    groupify :named_group_member
end

class Assignment < ActiveRecord::Base
  groupify :group_member
end

group.rb:

class Group < ActiveRecord::Base  
  groupify :group, members: [:users, :assignments], default_members: :users
end

groupmembership.rb:

class GroupMembership < ActiveRecord::Base  
  groupify :group_membership
end

schema.rb:

ActiveRecord::Schema.define(version: 20150301133633) do

  create_table "group_memberships", force: :cascade do |t|
    t.string  "member_type"
    t.integer "member_id"
    t.integer "group_id"
    t.string  "group_name"
    t.string  "membership_type"
  end

  add_index "group_memberships", ["group_id"], name: "index_group_memberships_on_group_id"
  add_index "group_memberships", ["group_name"], name: "index_group_memberships_on_group_name"
  add_index "group_memberships", ["member_id", "member_type"], name: "index_group_memberships_on_member_id_and_member_type"

  create_table "groups", force: :cascade do |t|
    t.string "type"
  end

create_table "users", force: :cascade do |t|
    t.string   "email",            null: false
    t.string   "crypted_password"
    t.string   "salt"
    t.datetime "created_at"
    t.datetime "updated_at"
    t.string   "name"
  end

  add_index "users", ["email"], name: "index_users_on_email", unique: true

end

1 Answer

Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points
Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points

Wait, is your GroupMembership model file name groupmembership.rb or is it a typo in the above post? The camel case suggests it should be group_membership.rb.

Andrew Stelmach
Andrew Stelmach
12,583 Points

It's groupmembership.rb. That might be it; I'll try it later.

Andrew Stelmach
Andrew Stelmach
12,583 Points

Worked! Thanks man. I feel a bit stupid, but it just goes to show why it's important to get a solid foundation of knowledge. I'm spending more time reading my book these days, rather than just hacking through code (but I do still hack a bit :-) )

Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points
Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points

Glad it worked :). I don't think this is explicitly explained anywhere. It's just a pattern I picked up at some point.