Rule

A rule engine written in python.

The rule is a json/yaml string or python object of a list expression. The expression is like [op, arg0, arg1, ..., argn], the op is the operator, and arg0..n is the arguments for the operator. Any argument can be another expression.

For writing convenience, the first argument will be tried to resolve as the context parameter. Or, you can just use the special var operator to indicate the context parameter.

Installing

pip install rule

Usage

>>> from rule import Rule
>>>
>>> context = dict(a=1, world='hello')
>>> Rule(['=', ['var', 'a'], 1]).match(context)
True
>>> Rule("['=', ['var', 'a'], 1]").match(context)
True
>>> Rule(['=', 'a', 1]).match(context)
True
>>> Rule(['=', 'hello', 'hello']).match(context)
True
>>> Rule(['=', 'world', 'hello']).match(context)
True
>>> Rule(['<', 'a', 10]).match(context)
True
>>> Rule(['=', ['>', 'a', 10], False]).match(context)
True
>>>
>>> context = dict(ldap_id='Harry', hosts='sa,sb,sc', reason='hehe', nologin=False,
...                group='wheel,sysadmin,platform', package='dev-python/sa-tools',
...                branch='release', cc='Tony,Mike',)
>>> Rule(['contains', 'hosts', 'sa,']).match(context)
True
>>> Rule(['contains', ['split', 'hosts', ','], 'sa']).match(context)
True
>>> Rule(['in', 'branch', 'master', 'release']).match(context)
True
>>> Rule(['=', 'ldap_id', 'Harry']).match(context)
True
>>> Rule(['match', 'package', 'dev-python/*']).match(context)
True
>>> Rule(['regex', 'package', 'dev-python/.*']).match(context)
True
>>> Rule(['is', 'nologin', False]).match(context)
True

See rule/op.py for more supported operators.

Development

make init
# make install
make test

License

http://tclh123.mit-license.org/