ConfigParser.get() defaults?

[Jon Clements]

On 7 May, 21:05, Tim Chase <python.l... at tim.thechases.com> wrote:
> With a normal dictionary, I can specify a default fallback value
> in the event the requested key isn't present:
>
>    d = {}
>    print d.get(42, 'Some default goes here')
>
> However, with the ConfigParser object, there doesn't seem to be
> any way to do a similar
>
>    cp = ConfigParser(...)
>    # ...
>    print cp.get('MySection', 'MyValue', 'Some default goes here')
>
> that, in the event either "MySection" doesn't exist in the config
> file, or "MyValue" doesn't exist within "MySection", it simply &
> quietly returns my default.  At the moment, I have to mimic this with
>
>    try:
>      val = cp.get('MySection', 'MyValue')
>    except (NoSectionError, NoOptionError), e:
>      val = 'Some default goes here'
>    print val
>
> which is a real pain when you have multiple options, some using
> various combinations of get(), getboolean(), getint(), or
> getfloat().  Yes, I can write some cheap wrappers to do these,
> but it feels like something that should be built-in.
>
> I've played with the DEFAULT, but that seems to just create its
> own section that I have to *ask* for:
>
>    cp.get('DEFAULT', 'MyValue')
>
> I've thumbed through the source to ConfigParser.py but don't see
> any indication that it's possible to do what I'd like short of
> wrapping all my cp.get*() calls in try/except blocks or creating
> a forked version of ConfigParser.py locally.  Is there anything
> I'm missing, or a better workaround to this?
>
> Thanks,
>
> -tkc

Not convinced about this, but a quick "work-around" would be something
like:

def get_config(config, section, option, ctype=str, default=None):
    if default is None:
        ret = config.get(section, option)
    else:
        confdict = config.__dict__.get('_sections')
        ret = confdict.get(section).get(option, default)
    return ctype(ret)

That should cover most exceptions and the get* functions..., just
provide your own factory function to post-parse it...

Of course, I'm probably missing something as usual...

Anyway, Cheers,

Jon.