Rails - Nov 2009 - After upgrading to Rails 2.3.4, Lazy Loaded attributes are never loaded. Broken?

I have an application that I started developing under 2.1 and have
progressed through 2.2 and am no attempting to run using 2.3.4.

The application is heavily reliant on ActiveRecord and the ability to
reference objects and attributes using dot notation.

eg:

if I have defined for class ARec
    named_scope :for_period, lambda {|f,t| {:conditions =>
[''from_date
between ? and ?'', f,t]}}

I typically call:
    from_date = ARec.for_period( c.d.e.from, f.g.h.i.to )

or similar within my code.

The problem is that under 2.2.2, c.d.e.from and f.g.h.i.to both loaded
the values from the database as needed, whereas under 2.3.4, when I
run the same code block, the from and to calls both get into
AssociationProxy.load_target (association_proxy.rb : 237) and Rails
determines that the instances have already been loaded, even though
their attribute lists are nil.

The only solution I have found so far is to add a parameter of true to
each object to force the loading.  But I don''t really want to do that
to the over 10,000 places in my code where I may need to do this.
What this really seems to indicate is that lazy loading of objects is
broken in Rails 2.3.4 if AR is marking records as loaded when it
hasn''t loaded the attributes.

What can I do (short of going back to Rails 2.2.x) to get Lazy Loading
working application wide for a system with over 400 separate models
and over 20,000 lines of code in my models?

On Nov 11, 7:25 am, Polydectes
<esmith...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> I have an application that I started developing under 2.1 and have
> progressed through 2.2 and am no attempting to run using 2.3.4.
>
> The application is heavily reliant on ActiveRecord and the ability to
> reference objects and attributes using dot notation.
>
I think that applies to most applications and is something that should
just work. Have you tried boiling down your problem to an example
small enough to post here ?

Fred
> eg:
>
> if I have defined for class ARec
>     named_scope :for_period, lambda {|f,t| {:conditions =>
[''from_date
> between ? and ?'', f,t]}}
>
> I typically call:
>     from_date = ARec.for_period( c.d.e.from, f.g.h.i.to )
>
> or similar within my code.
>
> The problem is that under 2.2.2, c.d.e.from and f.g.h.i.to both loaded
> the values from the database as needed, whereas under 2.3.4, when I
> run the same code block, the from and to calls both get into
> AssociationProxy.load_target (association_proxy.rb : 237) and Rails
> determines that the instances have already been loaded, even though
> their attribute lists are nil.
>
> The only solution I have found so far is to add a parameter of true to
> each object to force the loading.  But I don''t really want to do
that
> to the over 10,000 places in my code where I may need to do this.
> What this really seems to indicate is that lazy loading of objects is
> broken in Rails 2.3.4 if AR is marking records as loaded when it
> hasn''t loaded the attributes.
>
> What can I do (short of going back to Rails 2.2.x) to get Lazy Loading
> working application wide for a system with over 400 separate models
> and over 20,000 lines of code in my models?

I am trying to narrow this down as much as possible.  The problem is
that it''s so prevalent that I have dome the following:

Assuming the ARec from above contains a has_one relationship to a
Location such that
ARec.location is the related location.

In my code, I have the ARec loaded and I want to get the Location.  So
I do the following:

loc = ARec.location( true )

the result is a Location object in loc with @attributes,
@attributes_cache, and all records related to the Location class set
to nil.

I have created a small project (using NetBeans 6.8, Ruby 1.8.7, and
Rails 2.3.4) which shows the failure when you run "rake test:units"



On Nov 11, 3:24 am, Frederick Cheung
<frederick.che...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> On Nov 11, 7:25 am, Polydectes
<esmith...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> I have an
application that I started developing under 2.1 and have
> > progressed through 2.2 and am no attempting to run using 2.3.4.
>
> > The application is heavily reliant on ActiveRecord and the ability to
> > reference objects and attributes using dot notation.
>
> I think that applies to most applications and is something that should
> just work. Have you tried boiling down your problem to an example
> small enough to post here ?
>
> Fred
>
> > eg:
>
> > if I have defined for class ARec
> >     named_scope :for_period, lambda {|f,t| {:conditions =>
[''from_date
> > between ? and ?'', f,t]}}
>
> > I typically call:
> >     from_date = ARec.for_period( c.d.e.from, f.g.h.i.to )
>
> > or similar within my code.
>
> > The problem is that under 2.2.2, c.d.e.from and f.g.h.i.to both loaded
> > the values from the database as needed, whereas under 2.3.4, when I
> > run the same code block, the from and to calls both get into
> > AssociationProxy.load_target (association_proxy.rb : 237) and Rails
> > determines that the instances have already been loaded, even though
> > their attribute lists are nil.
>
> > The only solution I have found so far is to add a parameter of true to
> > each object to force the loading.  But I don''t really want to
do that
> > to the over 10,000 places in my code where I may need to do this.
> > What this really seems to indicate is that lazy loading of objects is
> > broken in Rails 2.3.4 if AR is marking records as loaded when it
> > hasn''t loaded the attributes.
>
> > What can I do (short of going back to Rails 2.2.x) to get Lazy Loading
> > working application wide for a system with over 400 separate models
> > and over 20,000 lines of code in my models?

On Nov 12, 7:44 am, Polydectes
<esmith...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> loc = ARec.location( true )
>
> the result is a Location object in loc with @attributes,
> @attributes_cache, and all records related to the Location class set
> to nil.
>
> I have created a small project (using NetBeans 6.8, Ruby 1.8.7, and
> Rails 2.3.4) which shows the failure when you run "rake
test:units"
>
What does the code for that project look like ?

Fred
> On Nov 11, 3:24 am, Frederick Cheung
<frederick.che...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> wrote:
>
>
>
> > On Nov 11, 7:25 am, Polydectes
<esmith...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> I have an
application that I started developing under 2.1 and have
> > > progressed through 2.2 and am no attempting to run using 2.3.4.
>
> > > The application is heavily reliant on ActiveRecord and the
ability to
> > > reference objects and attributes using dot notation.
>
> > I think that applies to most applications and is something that should
> > just work. Have you tried boiling down your problem to an example
> > small enough to post here ?
>
> > Fred
>
> > > eg:
>
> > > if I have defined for class ARec
> > >     named_scope :for_period, lambda {|f,t| {:conditions =>
[''from_date
> > > between ? and ?'', f,t]}}
>
> > > I typically call:
> > >     from_date = ARec.for_period( c.d.e.from, f.g.h.i.to )
>
> > > or similar within my code.
>
> > > The problem is that under 2.2.2, c.d.e.from and f.g.h.i.to both
loaded
> > > the values from the database as needed, whereas under 2.3.4, when
I
> > > run the same code block, the from and to calls both get into
> > > AssociationProxy.load_target (association_proxy.rb : 237) and
Rails
> > > determines that the instances have already been loaded, even
though
> > > their attribute lists are nil.
>
> > > The only solution I have found so far is to add a parameter of
true to
> > > each object to force the loading.  But I don''t really
want to do that
> > > to the over 10,000 places in my code where I may need to do this.
> > > What this really seems to indicate is that lazy loading of
objects is
> > > broken in Rails 2.3.4 if AR is marking records as loaded when it
> > > hasn''t loaded the attributes.
>
> > > What can I do (short of going back to Rails 2.2.x) to get Lazy
Loading
> > > working application wide for a system with over 400 separate
models
> > > and over 20,000 lines of code in my models?

Eric Smith wrote:
[...]
> 
> What can I do (short of going back to Rails 2.2.x) to get Lazy Loading
> working application wide for a system with over 400 separate models
> and over 20,000 lines of code in my models?
This is a side issue, but...refactor your codebase!  It''s a rare 
application indeed that needs 400 models, so I suspect you may have some 
stuff that should come out...

Best,
--
Marnen Laibow-Koser
http://www.marnen.org
marnen-sbuyVjPbboAdnm+yROfE0A@public.gmane.org
-- 
Posted via http://www.ruby-forum.com/.