Use Ruby's clos_tree gem without rails

Question

I want to try gem closure_tree to build a tree for my genealogy database. I installed the stone under Ruby MRI 2.3.0 in a Windows 7 window. The dependency options are listed in the error below.

$ gem install closure_tree Fetching: with_advisory_lock-3.0.0.gem (100%) Successfully installed with_advisory_lock-3.0.0 Fetching: closure_tree-6.2.0.gem (100%) Successfully installed closure_tree-6.2.0 2 gems installed 

When I try to execute the most minimalistic code, it fails, I suppose, because I do not use Rails and do not perform the migration, which I suppose creates the tag_hierachies table

My question is: can I use this stone without Rails, and if so, how?

 require 'active_record' require 'closure_tree' ActiveRecord::Base.establish_connection( :adapter => "sqlite3", :database => "sample.db" ) if !ActiveRecord::Base.connection.table_exists?('tags') ActiveRecord::Schema.define do create_table :tags do |table| table.column :name, :string table.column :parent_id, :integer end end end class Tag < ActiveRecord::Base has_closure_tree end grandparent = Tag.create(name: 'Grandparent') 

gives

 d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/sqlite3_adapter.rb:513:in `table_structure': Could not find table 'tag_hierarchies' (ActiveRecord::StatementInvalid) from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/sqlite3_adapter.rb:387:in `columns' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/schema_cache.rb:43:in `columns' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/attributes.rb:93:in `columns' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/attributes.rb:98:in `columns_hash' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/inheritance.rb:205:in `subclass_from_attributes?' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/inheritance.rb:54:in `new' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/persistence.rb:50:in `create!' from d:/Ruby/lib/ruby/gems/2.3.0/gems/closure_tree-6.2.0/lib/closure_tree/hierarchy_maintenance.rb:65:in `block in rebuild!' from d:/Ruby/lib/ruby/gems/2.3.0/gems/closure_tree-6.2.0/lib/closure_tree/support.rb:108:in `block (2 levels) in with_advisory_lock' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/abstract/database_statements.rb:211:in `transaction' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/transactions.rb:220:in `transaction' from d:/Ruby/lib/ruby/gems/2.3.0/gems/closure_tree-6.2.0/lib/closure_tree/support.rb:108:in `block in with_advisory_lock' from d:/Ruby/lib/ruby/gems/2.3.0/gems/with_advisory_lock-3.0.0/lib/with_advisory_lock/base.rb:77:in `yield_with_lock' from d:/Ruby/lib/ruby/gems/2.3.0/gems/with_advisory_lock-3.0.0/lib/with_advisory_lock/base.rb:65:in `yield_with_lock_and_timeout' from d:/Ruby/lib/ruby/gems/2.3.0/gems/with_advisory_lock-3.0.0/lib/with_advisory_lock/base.rb:48:in `with_advisory_lock_if_needed' from d:/Ruby/lib/ruby/gems/2.3.0/gems/with_advisory_lock-3.0.0/lib/with_advisory_lock/concern.rb:16:in `with_advisory_lock_result' from d:/Ruby/lib/ruby/gems/2.3.0/gems/with_advisory_lock-3.0.0/lib/with_advisory_lock/concern.rb:10:in `with_advisory_lock' from d:/Ruby/lib/ruby/gems/2.3.0/gems/closure_tree-6.2.0/lib/closure_tree/support.rb:107:in `with_advisory_lock' from d:/Ruby/lib/ruby/gems/2.3.0/gems/closure_tree-6.2.0/lib/closure_tree/hierarchy_maintenance.rb:63:in `rebuild!' from d:/Ruby/lib/ruby/gems/2.3.0/gems/closure_tree-6.2.0/lib/closure_tree/hierarchy_maintenance.rb:39:in `_ct_after_save' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activesupport-4.2.6/lib/active_support/callbacks.rb:432:in `block in make_lambda' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activesupport-4.2.6/lib/active_support/callbacks.rb:228:in `block in halting_and_conditional' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activesupport-4.2.6/lib/active_support/callbacks.rb:506:in `block in call' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activesupport-4.2.6/lib/active_support/callbacks.rb:506:in `each' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activesupport-4.2.6/lib/active_support/callbacks.rb:506:in `call' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activesupport-4.2.6/lib/active_support/callbacks.rb:92:in `__run_callbacks__' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activesupport-4.2.6/lib/active_support/callbacks.rb:778:in `_run_save_callbacks' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/callbacks.rb:302:in `create_or_update' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/persistence.rb:120:in `save' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/validations.rb:37:in `save' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/attribute_methods/dirty.rb:21:in `save' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/transactions.rb:286:in `block (2 levels) in save' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/transactions.rb:351:in `block in with_transaction_returning_status' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/abstract/database_statements.rb:213:in `block in transaction' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/abstract/transaction.rb:184:in `within_new_transaction' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/abstract/database_statements.rb:213:in `transaction' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/transactions.rb:220:in `transaction' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/transactions.rb:348:in `with_transaction_returning_status' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/transactions.rb:286:in `block in save' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/transactions.rb:301:in `rollback_active_record_state!' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/transactions.rb:285:in `save' from d:/Ruby/lib/ruby/gems/2.3.0/gems/activerecord-4.2.6/lib/active_record/persistence.rb:34:in `create' from C:/Users/Gebruiker/BoxSync/ruby_werk/acts_as_tree/closure_tree.rb:22:in `<main>' 

Answer 1

README installation instructions seem to focus only on Rails. However, it tells you that you need another table (in addition to the current current tags table) called tag_hierarchies .

In Rails, generating this table is part of the installation steps; Step 5 in the related documentation.

So, you must create a tag_hierarchies table with the following contents, which creates rails g closure_tree:migration tag in relation to the table structure. See create_hierarchies_table.rb.erb , as you can also add an index, as shown in this linked file.

So, updating your script to the following worked as expected for me:

 require 'active_record' require 'closure_tree' ActiveRecord::Base.establish_connection( :adapter => "sqlite3", :database => "sample.db" ) if !ActiveRecord::Base.connection.data_source_exists?('tags') ActiveRecord::Schema.define do create_table :tags do |table| table.column :name, :string table.column :parent_id, :integer end end end # You also need a corresponding model table name followed by "_hierarchies" table. # # Migration created based on # `https://github.com/mceachen/closure_tree/blob/master/lib/generators/closure_tree/templates/create_hierarchies_table.rb.erb` if !ActiveRecord::Base.connection.data_source_exists?(:tag_hierarchies) ActiveRecord::Schema.define do create_table :tag_hierarchies do |table| table.integer :ancestor_id, null: false table.integer :descendant_id, null: false table.integer :generations, null: false end end end class Tag < ActiveRecord::Base has_closure_tree end grandparent = Tag.create(name: 'Grandparent') grandparent.children.create(name: 'Father') grandparent.children.create(name: 'Uncle')