whatami: unobtrusive object self-identification for python¶

About¶

Whatami is an attempt to abstract configurability and experiment identifiability in a convenient way. It does so by leveraging object introspection and defining a simple, flexible and consistent API that python objects can adhere to.

It works this way:

Objects provide their own ids based on parameters=value dictionaries. They do so by returning an instance of the What class from a method called “what()” (and that’s all).
Optionally, this package provides a whatable decorator to provide automatic creation of What objects from the class dictionary, slots and properties. All attributes will be considered part of the configuration, except for those whose names start or end by ‘_’.

The id strings¶

They aim to look like they would be generated if __repr__ in python was always implemented taking into account recursion and exposing only result-changing parameters.

Versioning¶

Since release 2.0.0 whatami uses semantic versioning, where a major version bump happens also if the default id strings can be generated differently, even if no API actually changes.

Features¶

Represent your computations as standardized strings.
“whatamise” your library. Included support for:
- scikit-learn
- arch
- pyopy

Example¶

# Objects of this class provide a configuration (`What` object)
class DuckedConfigurable(object):
    def __init__(self, quantity, name, company=None, verbose=True):
       self.quantity = quantity
       self.name = name
       self.company = company
       self.verbose = verbose

    def what(self):
        return What('ducked', {'quantity': self.quantity, 'name': self.name, 'company': self.company})

duckedc = DuckedConfigurable(33, 'salty-lollypops', verbose=False)

# The configuration id string sorts by key alphanumeric order, helping id consistency
print duckedc.what().id()
# ducked#company=None#name='salty-lollypops'#quantity=33

# Using the whatable decorator makes objects gain a what() method;
# in this case, what() is infered automatically
@whatable
class Company(object):
    def __init__(self, name, city, verbose=True):
        super(Company, self).__init__()
        self.name = name
        self.city = city
        self._verbose = verbose  # not part of config
        self.social_reason_ = '%s S.A., %s' % (name, city)  # not part of config
cc = Company(name='Chupa Chups', city='Barcelona')
print cc.what().id()
# Company#city='Barcelona'#name='Chupa Chups'

# Ultimately, we can nest whatables...
duckedc = DuckedConfigurable(33, 'salty-lollypops', company=cc, verbose=False)
print duckedc.what().id()
# ducked#company="Company#city='Barcelona'#name='Chupa Chups'"#name='salty-lollypops'#quantity=33

# We can also decorate functions and partials - use with caution
@whatable
def buy(company, price=2**32, currency='euro'):
    return '%s is now mine for %g %s' % (company.name, price, currency)
print buy.what().id()
# buy#currency='euro'#price=4294967296