I am considering how to approach the problem of providing client balances. I have considered treating balances as virtual attributes in some fashion approximating this:
class Client < AR ... has_many :ar_transactions, :class => 'Transaction', :conditions => { :type => 'ar', :valid? = true }
def balance self.ar_transactions.sum(:balance) end
I am also thinking, at the moment, that the balance of a transaction is similarly a virtual attribute that might look like this:
class Transaction < AR ... has_many :details, :class => 'TransactionDetail', :conditions => { :valid? = true, ...
has_many :offsets, :class => 'TransactionJournal', :conditions => { ...
# I do not account for the separate treatment of debit and credit items # in this example
def balance offset = self.offsets.sum(:amount) total - offset end
def total self.details.sum(:amount) end
Is this the way I should do this? Is there a better way?
