python-wax - hierarchical configuration format and context object for Python

Quick Example

>>> from wax import Wax, parse_wax
>>> w = Wax(server=Wax(host='localhost'))
>>> w.server.port = 1234

>>> print 'hostname is %(server.host)s using port %(server.port)s' % w
hostname is localhost using port 1234

>>> s = str(w)
>>> print s

[server]
host = "localhost"
port = 1234

>>> w = parse_wax(s)
print w

[server]
host = "localhost"
port = 1234

Features

• Context objects can be serialized to / from string

• Simple hierarchical key structure

• Key order is maintained

• Values can be any JSON type

• Supports comments and annotations

Overview

Easy to construct in code:

>>> w = Wax(message='hello world', num=17)

Access values with indexes:

>>> w['num'] = 18

>>> w.message = 'hello again'

>>> w.get('missing.key', 'no problem')
'no problem'

This object translates directly to a file format. Reading the format will reconstruct the context object exactly. This allows for “round-trip” configuration that can be serialized to utf-8, edited, and read back in:

>>> w = Wax(state='New York', zip=10003)
>>> s = str(w)
>>> print s
state = "New York"
zip = 10003

>>> q = parse_wax(s)
>>> print q
state = "New York"
zip = 10003

Key order is preserved when keys are added individually. If you add them in the constructor, initial order is governed by kwargs (dict) hashing order:

>>> w = Wax(a=1, b=2, c=3)
>>> print w
a = 1
c = 3
b = 2

>>> w = Wax()
>>> w.a = 1
>>> w.b = 2
>>> w.c = 3
>>> print w
a = 1
b = 2
c = 3

Create sublevels by attaching a Wax instance to a key:

>>> w = Wax(level1=Wax(level2=Wax(property='value')))

>>> w = Wax()
>>> w.level1 = Wax()
>>> w.level1.level2 = Wax()
>>> w.level1.level2.property = 'value'

Serializing this:

>>> print w
[level1.level2]
property = "value"

Or you can set dotted keys to create nested values:

>>> w = Wax()
>>> w['foo.bar'] = 123
>>> print w.foo.bar
123

Dotted access can be used in formatting strings:

>>> w = Wax(server=Wax(host='localhost', port=1234))
>>> print 'hostname is %(server.host)s using port %(server.port)s' % w
hostname is localhost using port 1234