Re: [Modeling-users] Problem in module location

[Sebastien B. <sbi...@us...>]

        Hi,

<luk...@po...> wrote:
> Hi
>=20
> I notice a strange behavior. When I import this script showed below all is
> ok, Python finds the module "Matki" (sorry for strange names - ther are in
> Polish :-). But when I call function "PokazMatki()" I got this error.
> Interesting thing is that when I replace
> 	matki=3DEC.fetch('Matki')
> with
> 	matki=3DEC.fetch('Matki', rawRows=3D1)
> all is ok again. The package "BazaAdresowa" isn't in directory where is t=
his
> script. The package is in Python directory in subdirectory "GifExtensions=
".
> When I copy the package "BazaAdresowa" to the directory where the script =
is
> everything works fine again. Strange isn't it? Could you give me some
> explanation?
>=20
> #------
> from mx.DateTime import *
> from Modeling.EditingContext import EditingContext
> from GifExtensions.BazaAdresowa.Matki import Matki
>=20
> def PokazMatki():
>         EC=3DEditingContext()
>         matki=3DEC.fetch('Matki')
> #------

This happens because the framework is not able to find the class: I'm quite
sure that your model have packageName=3D"BazaAdresowa", with entity's
moduleName=3DMatki and className=3DMatki (whatever that means ;)

When you fetch, the framework tries to do the equivalent of:
"from <packageName>.<moduleName> import <className>",=20
in your case: "from BazaAdresowa.Matki import Matki".

But this does not work, because as your script shows it, package
BazaAdresowa is in GifExtensions, not in the python path. So the
solution is: either add BazaAdresowa in your python path, or change the
model so that its package name is "GifExtensions.BazaAdresowa".

In any case and as a general rule, wherever in the python code the
statement "from <packageName>.<moduleName> import <className>" fails,
the framework will equally fails. This is something that should probably
be put somewhere, I'll try not to forget and add that to the faq.

That's why the framework says:
> ImportError: Unable to locate class BazaAdresowa.Matki.Matki corresponding
> to entity 'Matki'.
> It is possible that the model's packageName, or the entity's moduleName or
> className do not correspond to where the module is installed --for exampl=
e,
> you might have moved it to a sub-package. You can solve this easily by
> updating your model so that 'packageName.moduleName.className' points to
> the exact location where the class is installed
>=20
> Original exception was: ImportError: No module named BazaAdresowa


  Back on your other question:
> Interesting thing is that when I replace
> 	matki=3DEC.fetch('Matki')
> with
> 	matki=3DEC.fetch('Matki', rawRows=3D1)
> all is ok again.

fetch w/ rawRows does not try to instanciate any objects, it just
returns a dictionary from the db -> it does not try to import any class
in the process, and that's why it does not fail.

  I hope I succedeed to make it clear, if not, you can keep picking on
  me ;)

-- S=E9bastien.