uplook 0.4.2

A Python library and syntax to perform external lookups to retrieve argument values.

What?

An opinionated Python module which facilitates configuration value storage and access with support for external value lookups.

Examples

Provided kwargs are accessible as attributes

>>>> from uplook import UpLook
>>>> u = UpLook(one=1, two=2)
>>>> u
UpLook({'two': 2, 'one': 1})
>>>> u.value.one
1

Dict argument values are recursively mapped to attributes

>>>> from uplook import UpLook
>>>> u = UpLook(levels = {"level1":{"level2":{"level3": "hello"}}})
>>>> u
UpLook({'levels': {'level1': {'level2': {'level3': 'hello'}}}})
>>>> u.value.levels.level1.level2.level3
'hello'

Get the data portion without all helper methods

>>>> from uplook import UpLook
>>>> u = UpLook(one=1, two=2)
>>>> u
UpLook({'two': 2, 'one': 1})
>>>> data = u.get()
>>>> data.one
1

Get a simple dict representation of the data

>>>> from uplook import UpLook
>>>> u = UpLook(one=1, two=2)
>>>> u
UpLook({'two': 2, 'one': 1})
>>>> data = u.dump()
{'two': 2, 'one': 1}

Iterate over key/value pairs of a data container

>>>> from uplook import UpLook
>>>> u = UpLook(one=1, two=2)
>>>> u
UpLook({'two': 2, 'one': 1})
>>>> for key, value in u.get():
....     print "key: %s, value: %s" % (key, value)
....
key: two, value: 2
key: one, value: 1

External lookup values

Some value lookup function

from uplook import UpLook
from uplook.errors import NoSuchValue


def someLookupFunction(key):
    data = {"value.number.one": "hi",
            "value.number.two": "this",
            "value.number.three": "is",
            "value.number.four": "a",
            "value.number.five": "silly",
            "value.number.six": "demo"
            }

    try:
        return data[key]
    except KeyError:
        raise NoSuchValue("%s is an unknown value." % (key))


def randomInt(max):
    return random.randint(0, max)

Initialize an Uplook instance with a dynamic and static lookup

>>> instance = UpLook(static='~fubar("value.number.one", "unknown")',
>>>                   dynamic='~~random(100)',
>>>                   normal='hello')

List all user defined lookup functions

>>> for function in instance.listfunctions():
        print function
fubar
random
>>>

Register lookup functions

>>> instance.registerLookup("fubar", someLookupFunction)
>>> instance.registerLookup("random", randomInt)

Access a static lookup value

>>> print test.value.static
hi
>>> print test.value.static
hi

Access a dynamic lookup value

>>> print test.value.dynamic
>>> 81
>>> print test.value.dynamic
>>> 16

Each time test.value.dynamic is called, the lookup function is executed because of the double tilde (~~) in the argument value