I’ve searched for information about this and compared what I have to the
solutions I can find, here and elsewhere. I found some good and useful
information, yet my stuff still doesn’t work. I was hoping somebody here
could spot something. I’m using rails 2.1.2 and I’m pretty new to ruby
and rails.
My goal is a fairly simple many-to-many relationship linking “modules”
and “users”. There’s 3 tables (I know the names are inconsistent - it’s
a little strange because it was an existing database that I dumped into
rails):
- module: a module definition
- users: the users of the system
- module_user_map: join table linking modules and users
My data model (from schema.rb) looks in part like this:
create_table “module”, :force => true do |t|
t.string “name”, :default => “”, :null => false
t.integer “status”, :default => 0, :null => false
…
end
create_table “module_user_map”, :force => true do |t|
t.integer “module”, :default => 0, :null => false
t.integer “user”, :default => 0, :null => false
…
end
create_table “users”, :force => true do |t|
t.string “first_name”, :limit => 45
t.string “last_name”, :limit => 45
t.string “login”, :limit => 45
…
end
Here’s the corresponding files in app/models directory. It appears that
I could not use “module” as the model name because that is a reserved
word in rails, so I had to prepend “project_” to the “module” names.
This might be where I messed up, I don’t know.
=============== project_module.rb ===================
class ProjectModule < ActiveRecord::Base
set_table_name “module”
has_many :module_user_maps, :dependent => :delete_all
has_many :users, :through => :module_user_maps
end
=============== user.rb ===================
class User < ActiveRecord::Base
has_many :module_user_maps, :dependent => :delete_all
has_many :project_modules, :through => :module_user_maps
end
=============== module_user_maps.rb ===================
class ModuleUserMaps < ActiveRecord::Base
set_table_name “module_user_map”
belongs_to :user
belongs_to :project_module
end
So I run from the script/console (same thing happens in the server):
u=User.find(2)
=> #<User id: 2, first_name: “Site”, last_name: “User”, login: “user”,
password:
“password”, organization: 2, roles: “public”, last_modified:
“2008-11-17 12:09:
10”, last_modified_by: nil, last_login: “2008-11-17 12:10:06”, status:
1, date_c
reated: nil, address1: nil, address2: nil, city: nil, state: nil,
postal_code: n
il, email: nil>u.project_modules
NameError: uninitialized constant User::ModuleUserMap
from
C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.1.2/lib/active_suppo
rt/dependencies.rb:493:in `const_missing’
… etc …u.module_user_maps
NameError: uninitialized constant User::ModuleUserMap
from
C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.1.2/lib/active_suppo
rt/dependencies.rb:493:inconst_missing' from C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.1.2/lib/active_record /base.rb:1914:incompute_type’
… etc …
I’m hoping somebody can spot something fairly simple. This should not be
a hard thing to do. Thanks!