[Chicago] Avoiding circular imports

[Adam Yala]

Ken, thank you for your example. I had to think through it for a while, but
that cleared up a lot of the import behavior I didn't understand.

I think I now have the insight to go back in and fix my circular import
errors. I'll report back with my findings (and hopefully a github repo so
people can see what I'm seeing).

On Sun, Jan 8, 2017 at 7:30 PM, Ken Schutte <kenschutte at gmail.com> wrote:

> Try this experiment:
>
> === api.py ===
> print("api: top")
> import models
> print("api: models.Company exits? " + repr(hasattr(models,"Company")))
>
> === models.py ===
> print("models: top")
> import api
> class Company:
>     pass
> print("models: Company has been defined")
>
> run it:
> $ python api.py
> api: top
> models: top
> api: top
> api: models.Company exits? False
> models: Company has been defined
> api: models.Company exits? True
>
> It can be a bit confusing, but hopefully it shows what is happening
> and how imports work. Your best bet is probably to rearrange things.
> For example, use models.Company within a function (wouldn't be called
> directly when being imported), then call that from somewhere else.
>
> Ken
>
>
>
> On Sun, Jan 8, 2017 at 4:26 PM, Adam Yala <adamkyala at gmail.com> wrote:
> > I tried their method, when I did I got an AttributeError: module 'models'
> > has no attribute 'Company' even through it most definitely does contain
> that
> > class.
> >
> > On Sun, Jan 8, 2017 at 4:12 PM, Joshua Herman <zitterbewegung at gmail.com>
> > wrote:
> >>
> >> Searching on how to fix this on stack overflow it appears you can do
> this
> >> with absolute imports.
> >>
> >> http://stackoverflow.com/questions/7336802/how-to-
> avoid-circular-imports-in-python
> >> > On Jan 8, 2017, at 4:05 PM, Adam Yala <adamkyala at gmail.com> wrote:
> >> >
> >> > I'm trying to write a python wrapper for a web api. I have two files,
> >> > api.py and models.py. api.py contains a Client class used to make
> requests
> >> > to the web api. models.py contains objects from the web api in python
> form.
> >> >
> >> > api.py has the line: from models import Company
> >> > models.py has the line: from api import Client
> >> >
> >> > The Company class uses the Client class to make other needed web api
> >> > calls (like getting Employees). The Client class returns instances of
> >> > Company after web api calls.
> >> >
> >> > However, I'm getting circular import errors. Is there a safer way to
> >> > implement these imports? I've tried absolute imports and relative
> imports,
> >> > but both throw errors.
> >> >
> >> > If anyone has any guides or good reads on writing web api wrappers,
> I'd
> >> > love to give them a read. My google-fu has failed me on finding good
> >> > resources.
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> >>
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