Initial version for the recreate_table plugin

Author: til

README

@@ -0,0 +1,13 @@
+RecreateTable
+=============
+
+Introduction goes here.
+
+
+Example
+=======
+
+Example goes here.
+
+
+Copyright (c) 2009 [name of plugin creator], released under the MIT license

Rakefile

@@ -0,0 +1,11 @@
+require 'rake'
+require 'spec/rake/spectask'
+
+desc 'Default: run specs.'
+task :default => :spec
+
+desc 'Run the specs'
+Spec::Rake::SpecTask.new(:spec) do |t|
+  t.spec_opts = ['--colour --format progress --loadby mtime --reverse']
+  t.spec_files = FileList['spec/**/*_spec.rb']
+end

init.rb

@@ -0,0 +1,2 @@
+# Include hook code here
+require 'recreate_table'

install.rb

@@ -0,0 +1 @@
+# Install hook code here

lib/recreate_table.rb

@@ -0,0 +1,38 @@
+# RecreateTable
+
+ActiveRecord::ConnectionAdapters::SchemaStatements.module_eval do
+
+  def recreate_table(table, options={})
+    old_table = "#{table}_old"
+    as = options[:as] || "SELECT * FROM #{old_table}"
+
+    model = table.to_s.titleize.singularize.constantize
+    columns = model.columns.dup
+    id_sequence = "#{table}_id_seq"
+
+    transaction do
+
+      rename_table table, old_table
+
+      execute "CREATE TABLE #{table} AS (#{as})"
+
+      columns.each do |column|
+        if column.primary
+          execute "ALTER TABLE #{table} ADD PRIMARY KEY (#{column.name})"
+          execute "ALTER TABLE #{table} ALTER COLUMN #{column.name} SET DEFAULT nextval('#{id_sequence}'::regclass)"
+          execute "ALTER SEQUENCE #{id_sequence} OWNED BY #{table}.id"
+        else
+          change_column table, column.name, column.type, { :null => column.null , :default => column.default }
+        end
+      end
+      
+      indexes(old_table).each do |index|
+        execute "DROP INDEX #{index.name}"
+        add_index table, index.columns, :name => index.name, :unique => index.unique
+      end
+
+      drop_table old_table
+    end
+  end
+end
+

spec/debug.log

@@ -0,0 +1,124 @@
+require File.dirname(__FILE__) + '/spec_helper'
+
+describe "The RecreateTable plugin" do
+  
+  it "should add a command to schema commands" do
+    ActiveRecord::Base.connection.should respond_to(:recreate_table)
+  end
+end
+
+
+describe "recreate_table" do
+  class Foo < ActiveRecord::Base; end
+
+  before(:each) do
+    Foo.connection.create_table(:foos) do |t|
+      t.integer :bar
+      t.integer :baz, :null => false, :default => 0
+    end
+    
+    Foo.create!(:bar => 123)
+  end
+
+  it "should have Foos" do
+    Foo.count.should == 1
+  end
+
+  it "should keep the contents of the table" do
+    Foo.connection.recreate_table :foos
+    
+    Foo.count.should == 1
+  end
+  
+  it "should keep the primary key" do
+    Foo.connection.recreate_table :foos
+
+    new = Foo.create!
+    new.id.should_not be_nil
+  end
+  
+  it "should allow to insert further rows" do
+    Foo.connection.recreate_table :foos
+
+    lambda {
+      Foo.create!
+      Foo.create!
+      Foo.create!
+    }.should_not raise_error
+  end
+  
+  it "should keep defaults" do
+    Foo.connection.recreate_table :foos
+    Foo.reset_column_information
+
+    baz = Foo.columns.find { |c| c.name == 'baz' }
+
+    baz.default.should == 0
+  end
+  
+  it "should allow to create with default" do
+    Foo.connection.recreate_table :foos
+    Foo.reset_column_information
+
+    new = Foo.create!
+    new.baz.should == 0
+  end
+  
+  it "should keep NOT NULL constraint" do
+    Foo.connection.recreate_table :foos
+    Foo.reset_column_information
+
+    baz = Foo.columns.find { |c| c.name == 'baz' }
+
+    baz.null.should be_false
+  end
+end
+
+
+describe "recreate_table with new columns" do
+  class Foo < ActiveRecord::Base; end
+
+  before(:each) do
+    Foo.connection.create_table(:foos) do |t|
+      t.integer :bar
+    end
+    Foo.create!
+  end
+
+  it "should allow to add new columns" do
+    Foo.connection.recreate_table :foos, :as => "SELECT *, 123 AS baz FROM foos_old"
+    Foo.reset_column_information
+    
+    Foo.first.baz.should == 123
+  end
+end
+
+
+describe "recreate_table with indices" do
+  class Foo < ActiveRecord::Base; end
+
+  before(:each) do
+    Foo.connection.create_table(:foos) do |t|
+      t.integer :bar
+      t.integer :baz
+    end
+    Foo.connection.add_index :foos, :bar
+    Foo.connection.add_index :foos, :baz, :unique => true
+  end
+
+  it "should recreate the indices" do
+    Foo.connection.recreate_table :foos
+    Foo.reset_column_information
+    
+    index = Foo.connection.indexes(:foos).find { |i| i.name == 'index_foos_on_bar' }
+    index.should_not be_nil
+  end
+  
+  it "should retain uniqueness of indices" do
+    Foo.connection.recreate_table :foos
+    Foo.reset_column_information
+    
+    index = Foo.connection.indexes(:foos).find { |i| i.name == 'index_foos_on_baz' }
+    index.unique.should be_true
+  end
+end

spec/recreate_table_spec.rb

@@ -0,0 +1,10 @@
+begin
+  require File.dirname(__FILE__) + '/../../../../spec/spec_helper'
+rescue LoadError
+  puts "You need to install rspec in your base app"
+  exit
+end
+
+plugin_spec_dir = File.dirname(__FILE__)
+ActiveRecord::Base.logger = Logger.new(plugin_spec_dir + "/debug.log")
+

spec/spec_helper.rb

@@ -0,0 +1,4 @@
+# desc "Explaining what the task does"
+# task :recreate_table do
+#   # Task goes here
+# end

tasks/recreate_table_tasks.rake

@@ -0,0 +1 @@
+# Uninstall hook code here