crython 0.0.1

Cron scheduling for python functions.

# crython [](https://travis-ci.org/ahawker/crython)
crython is a lightweight task (function) scheduler using [cron](http://en.wikipedia.org/wiki/Cron) expressions written in python.

### Status
This module is currently under development.

### Installation
To install crython, simply:
```bash
$ pip install crython
```

### Usage
Crython supports seven fields (seconds, minutes, hours, day of month, month, weekday, year).

Call a function once a minute:
```python
import crython

#Fire once a minute.
@crython.job(minute=0)
def foo():
print "... while heavy sack beatings are up a shocking nine hundred percent?"
```

Call a function every ten seconds:
```python
#Fire every 10 seconds.
@crython.job(second=range(0,60,10))
def foo():
print "I'm a big four-eyed lame-o and I wear the same stupid sweater every day."
```

Call a function with a single cron expression:
```python
#Fire every 10 seconds.
@crython.job(second='*/10')
def foo():
print "Hail to the thee Kamp Krusty..."
```

Call functions with a full cron expression:
```python
#Fire once a week.
@crython.job(expr='0 0 0 * * 0 *')
def foo():
print "Back in line, maggot!"
```

Call functions with positional and/or keyword arguments:
```python
#Fire every second.
@crython.job(second=0, 10, 20, name='Homer Simpson')
def sum(x, y, name):
print "Hello {0}. The sum is {1}".format(name, x+y)
```

Call functions with [predefined keywords](http://en.wikipedia.org/wiki/Cron#Predefined_scheduling_definitions):
```python
#Fire once a day.
@crython.job(expr='@daily')
def foo():
print "That's where I saw the leprechaun. He tells me to burn things!"
```

Start the global job scheduler:
```python
if __name__ == '__main__':
crython.tab.start()
```

### TODO
- Keyword support (yearly, weekly, daily, etc)
- Support "L", "W" and "#" specials.
- Determine time delta from now -> next time expression is valid.

### Contributing
If you would like to contribute, simply fork the repository, push your changes and send a pull request.

### License
Crython is available under the [MIT license](https://github.com/ahawker/crython/blob/master/LICENSE.md).

### See Other
There are similar python cron libraries out there.
See:
[pycron](http://www.kalab.com/freeware/pycron/pycron.htm),
[python-crontab](http://pypi.python.org/pypi/python-crontab/),
[cronex](https://github.com/jameseric/cronex).