Excuse me, a little more discussion please. In my past design, there should be ONLY ONE Loan record between two people in a specific currency. The composite keys match this requirement, don't they? But to make it immutable.
On Jan 13, 2011, at 3:17 AM, RipTheJacker wrote: > Those won't make it immutable, but the key does need to be unique. So, > unless you can only have ONE Loan per Person you should probably > change those too. Rather than making them keys you probably mean to > have them as indexes, which I DataMapper does for you, and add an :id > Serial primary key to the model, the same as it is in your MoneyFlow > model. > > On Jan 12, 12:28 am, Zhi-Qiang Lei <[email protected]> wrote: >> Hi, >> >> This model also has two more keys, they make a composite keys. This will >> also make it immutable? >> >>>>>> belongs_to :loaner, Person, :key => true >>>>>> belongs_to :loanee, Person, :key => true >> >> On Jan 12, 2011, at 3:15 AM, RipTheJacker wrote: >> >> >> >> >> >>> Ok. It's because of this: >> >>> property :currency, Enum[*CURRENCY_CODES], :key => true >> >>> You can't have :key => true on an Enum property since it is not >>> unique. >> >>> On Jan 10, 11:22 pm, Zhi-Qiang Lei <[email protected]> wrote: >>>> Hi, >> >>>> I still get the error with your spec code, here is the backtrace. >> >>>> Failures: >> >>>> 1) Loan#count! when a loan exists from giver to receiver >>>> Failure/Error: Loan.count!(money_flow) >>>> DataMapper::ImmutableError: >>>> Immutable resource cannot be modified >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/dm-core-1.0.2/lib/dm-core/r >>>> esource/state/immutable.rb:16:in `set' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/dm-core-1.0.2/lib/dm-core/m >>>> odel/property.rb:251:in `amount=' >>>> # ./lib/models.rb:49:in `count!' >>>> # ./spec/models_spec.rb:64:in `block (4 levels) in <top (required)>' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-expectations-2.4.0/li >>>> b/rspec/matchers/change.rb:17:in `call' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-expectations-2.4.0/li >>>> b/rspec/matchers/change.rb:17:in `matches?' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-expectations-2.4.0/li >>>> b/rspec/expectations/handler.rb:34:in `handle_matcher' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-expectations-2.4.0/li >>>> b/rspec/expectations/extensions/kernel.rb:50:in `should_not' >>>> # ./spec/models_spec.rb:63:in `block (3 levels) in <top (required)>' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example.rb:49:in `instance_eval' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example.rb:49:in `block (2 levels) in run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example.rb:98:in `with_around_hooks' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example.rb:46:in `block in run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example.rb:91:in `block in with_pending_capture' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example.rb:90:in `catch' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example.rb:90:in `with_pending_capture' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example.rb:45:in `run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example_group.rb:261:in `block in run_examples' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example_group.rb:257:in `map' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example_group.rb:257:in `run_examples' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example_group.rb:231:in `run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example_group.rb:232:in `block in run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example_group.rb:232:in `map' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/example_group.rb:232:in `run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/command_line.rb:27:in `block (2 levels) in run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/command_line.rb:27:in `map' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/command_line.rb:27:in `block in run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/reporter.rb:12:in `report' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/command_line.rb:24:in `run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/runner.rb:55:in `run_in_process' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/runner.rb:46:in `run' >>>> # >>>> /Users/siegfried/.rvm/gems/ruby-1.9.2-p136/gems/rspec-core-2.4.0/lib/rspec/ >>>> core/runner.rb:10:in `block in autorun' >> >>>> On Jan 11, 2011, at 7:05 AM, RipTheJacker wrote: >> >>>>> You should probably just change that spec. The element that you want >>>>> to test is a proc (you hope) getting invoked inside of the subject >>>>> block, which is a weird pattern, and you don't need the #let blocks >>>>> really, since you only use those objects once. >> >>>>> Try: >> >>>>> describe "#count!" do >>>>> specify "when a loan exists from giver to receiver" do >>>>> loan = Loan.gen >>>>> money_flow = MoneyFlow.gen(:giver => loan.loaner, :receiver => >>>>> loan.loanee, :currency => loan.currency) >>>>> expect do >>>>> Loan.count!(money_flow) >>>>> end.to_not change(Loan, :count) >>>>> end >>>>> end >> >>>>> I'm assuming you are using rspec 2, though it will work in rspec 1.x >>>>> with a syntax change. If you still get that error, post the new >>>>> backtrace here. At the very least the spec and the backtrace will be >>>>> more meaningful this way, and may be easier to debug (I hope). >> >>>>> On Jan 10, 10:42 am, Zhi-Qiang Lei <[email protected]> wrote: >>>>>> Hi, >> >>>>>> I have some code as follow. >> >>>>>> class Loan >>>>>> include DataMapper::Resource >>>>>> belongs_to :loaner, Person, :key => true >>>>>> belongs_to :loanee, Person, :key => true >>>>>> property :currency, Enum[*CURRENCY_CODES], :key => true >>>>>> property :amount, Decimal, :scale => 2, :default => 0 >> >>>>>> def self.count!(money_flow) >>>>>> loan = get(money_flow.currency, money_flow.giver_id, >>>>>> money_flow.receiver_id) >>>>>> loan.amount += money_flow.amount >>>>>> end >> >>>>>> # more code... >>>>>> end >> >>>>>> class MoneyFlow >>>>>> include DataMapper::Resource >>>>>> belongs_to :giver, Person >>>>>> belongs_to :receiver, Person >> >>>>>> property :id, Serial >>>>>> property :amount, Decimal, :scale => 2, :min => 0.01 >>>>>> property :currency, Enum[*CURRENCY_CODES], :default => :CNY >> >>>>>> # more code... >>>>>> end >> >>>>>> When I test the "count!" class method as follow: >> >>>>>> describe "#count!" do >>>>>> subject { lambda { Loan.count!(money_flow) } } >>>>>> context "when a loan exists from giver to receiver" do >>>>>> let!(:loan) { Loan.gen } >>>>>> let(:money_flow) { MoneyFlow.gen(:giver => loan.loaner, :receiver >>>>>> => loan.loanee, :currency => loan.currency) } >>>>>> it { should_not change(Loan, :count) } >>>>>> end >>>>>> end >> >>>>>> It tells me I got a Immutable Error. I feel strange on that. They have >>>>>> keys, and I didn't destroy the record. Can you see why? Thanks. >> >>>>>> 1) Loan#count! when a loan exists from giver to receiver >>>>>> Failure/Error: subject { lambda { Loan.count!(money_flow) } } >>>>>> DataMapper::ImmutableError: >>>>>> Immutable resource cannot be modified >>>>>> # ./lib/models.rb:49:in `count!' >>>>>> # ./spec/models_spec.rb:59:in `block (4 levels) in <top (required)>' >>>>>> # ./spec/models_spec.rb:63:in `block (4 levels) in <top (required)>' >> >>>>>> On Jan 10, 2011, at 11:34 PM, Ted Han wrote: >> >>>>>>> Objects are immutable when they've been deleted or frozen for some >>>>>>> reason. Deleting a record from your data store will always result in >>>>>>> that record being frozen. >> >>>>>>> Is there a specific problem that you're having? >> >>>>>>> -T >> >>>>>>> On Mon, Jan 10, 2011 at 10:23 AM, Zhi-Qiang Lei >>>>>>> <[email protected]> wrote: >>>>>>> Dear All, >> >>>>>>> Could anyone answer me when a resource should be immutable? And why? >>>>>>> Thanks. >> >>>>>>> Best regards, >>>>>>> Zhi-Qiang Lei >>>>>>> [email protected] >> >>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "DataMapper" group. >>>>>>> To post to this group, send email to [email protected]. >>>>>>> To unsubscribe from this group, send email to >>>>>>> [email protected]. >>>>>>> For more options, visit this group >>>>>>> athttp://groups.google.com/group/datamapper?hl=en. >> >>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "DataMapper" group. >>>>>>> To post to this group, send email to [email protected]. >>>>>>> To unsubscribe from this group, send email to >>>>>>> [email protected]. >>>>>>> For more options, visit this group >>>>>>> athttp://groups.google.com/group/datamapper?hl=en. >> >>>>>> Best regards, >>>>>> Zhi-Qiang Lei >>>>>> [email protected] >> >>>>> -- >>>>> You received this message because you are subscribed to the Google Groups >>>>> "DataMapper" group. >>>>> To post to this group, send email to [email protected]. >>>>> To unsubscribe from this group, send email to >>>>> [email protected]. >>>>> For more options, visit this group >>>>> athttp://groups.google.com/group/datamapper?hl=en. >> >>>> Best regards, >>>> Zhi-Qiang Lei >>>> [email protected] >> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "DataMapper" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]. >>> For more options, visit this group >>> athttp://groups.google.com/group/datamapper?hl=en. >> >> Best regards, >> Zhi-Qiang Lei >> [email protected] > > -- > You received this message because you are subscribed to the Google Groups > "DataMapper" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/datamapper?hl=en. > Best regards, Zhi-Qiang Lei [email protected] -- You received this message because you are subscribed to the Google Groups "DataMapper" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/datamapper?hl=en.
