Class: ActiveRecord::Base

Inherits:
Object show all
Defined in:
lib/webget_ramp/active_record.rb

Overview

:doc:

Class Method Summary collapse

Class Method Details

.create_or_update(options = {}) ⇒ Object

Create a record, or update a record if value passed matches a field in the AR object; includes method_missing function to make code more readable

Most common use will be for testing (fixture/mock object generation)

Three versions of method included: create_or_update create_or_update_by create_or_update_by_xxx (where xxx is a field name)

Inspired by www.intridea.com/2008/2/19/activerecord-base-create_or_update-on-steroids-2

Example

{ “admin” => [“Administrator”, 1000], 

"member"    => ["Member", 1], 
"moderator" => ["Moderator", 100],
"disabled"  => ["Disabled User", -1] }.each_pair do |key, val|
  Role.create_or_update_by_key(:key => key, :name => val[0], :value => val[1])

end



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# File 'lib/webget_ramp/active_record.rb', line 31

def self.create_or_update(options = {})
  self.create_or_update_by(:id, options)
end

.create_or_update_by(condition_keys, attribute_pairs = {}) ⇒ Object

Create or update a record by field (or fields). This will look for each field name as a key in the options hash.

Example

attributes={:name="John Smith", :email=>"[email protected]", :birthdate=>'1980/01/01'}
User.create_or_update_by(:email,attributes)
=> if a user with that email exists then update his name and birthdate, else create him

Example with multiple conditions

attributes={:name="John Smith", :email=>"[email protected]", :birthdate=>'1980/01/01'}
User.create_or_update_by([:name,:birthdate],attributes)
=> if a user with that name and birthdate exists then update his email, else create him

The fields can be any mix of symbols or strings. The option keys can be any mix of symbols or strings.



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# File 'lib/webget_ramp/active_record.rb', line 52

def self.create_or_update_by(condition_keys, attribute_pairs = {})
  condition_pairs=[*condition_keys].map{|x| [x,(attribute_pairs.delete(x)||attribute_pairs.delete(x.to_s)||attribute_pairs.delete(x.to_sym))]}.to_h
  record = find(:first, :conditions => condition_pairs) || self.new
  if record.new_record? then attribute_pairs.merge!(condition_pairs) end
  attribute_pairs.each_pair{|k,v| record.send k.to_s+'=', v}
  record.save!
  return record
end

.included(base) ⇒ Object

For alias method chain



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# File 'lib/webget_ramp/active_record.rb', line 103

def self.included(base)
  # base == ActiveRecord::Base (the class)
  base.class_eval do
      # class_eval makes self == ActiveRecord::Base, and makes def define instance methods.
      extend ClassMethods
      # If has_many were an instance method, we could do this
      #   alias_method_chain :has_many, :association_option; end            
      # but it's a class method, so we have to do the alias_method_chain on  
      # the meta-class for ActiveRecord::Base, which is what class << self does.   
      class << self;  alias_method_chain :method_missing, :create_or_update;  end
    end
end

.method_missing_with_create_or_update(method_name, *args) ⇒ Object

Method missing for create_or_update_by_xxx that forwards to #create_or_update_by

Example

MyModel.create_or_update_by_foo(options)
=> MyModel.create_or_update_by(:foo,option)



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# File 'lib/webget_ramp/active_record.rb', line 93

def self.method_missing_with_create_or_update(method_name, *args) 
  if match = method_name.to_s.match(/create_or_update_by_([a-z0-9_]+)/)  
    field = match[1]
    return create_or_update_by(field,*args)
  end
  return method_missing_without_create_or_update(method_name, *args)
end

.seed(condition_keys, attribute_pairs = {}) ⇒ Object

Set up a database with initial data, e.g. in rake db:seed method.

This will look for each field name as a key in the options hash.

This method calls #create_or_update_by (and you may want to change this behavior to do more, e.g. to test that a DB and table exists).

Example

attributes={:name="John Smith", :email=>"[email protected]", :birthdate=>'1980/01/01'}
User.create_or_update_by(:email,attributes)
=> if a user with that email exists then update his name and birthdate, else create him

Example with multiple conditions

attributes={:name="John Smith", :email=>"[email protected]", :birthdate=>'1980/01/01'}
User.create_or_update_by([:name,:birthdate],attributes)
=> if a user with that name and birthdate exists then update his email, else create him

The fields can be any mix of symbols or strings. The option keys can be any mix of symbols or strings.



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# File 'lib/webget_ramp/active_record.rb', line 82

def self.seed(condition_keys, attribute_pairs = {})
  self.create_or_update_by(condition_keys, attribute_pairs)
end