crontabs 0.1.4

# Crontabs
Crontabs is a small library that makes it simple to schedule python functions to run on a schedule.
Crontabs was inspired by the excellent [schedule](https://github.com/dbader/schedule) library for python,

In addition to having a slightly different API, Crontabs differs from the schedule module in the following
ways.

* You do not need to provide your own event loop.
* Job timing is guarenteed not to drift over time. For example, if you specify to run a job every five minutes,
you can rest assured that it will always run at 5, 10, 15, etc. passed the hour with no drift.
* The python functions are all run in child processes. Not only does this enable asynchronous scheduling,
it also helps mitigate python memory problems due to the
[high watermark issue](https://hbfs.wordpress.com/2013/01/08/python-memory-management-part-ii/)


# Installation
```bash
pip install crontabs
```
# Usage

### Schedule a single job
```python
from crontabs import Cron, Tab
from datetime import datetime


def my_job(*args, **kwargs):
print('args={} kwargs={} running at {}'.format(args, kwargs, datetime.now()))


# Will run with a 5 minute interval synced to the top of the minute
Cron().schedule(
Tab(name='run_my_job').every(seconds=5).run(my_job, 'my_arg', my_kwarg='hello')
).go()

```

### Schedule multiple jobs
```python
from crontabs import Cron, Tab
from datetime import datetime


def my_job(*args, **kwargs):
print('args={} kwargs={} running at {}'.format(args, kwargs, datetime.now()))


# All logging messages are sent to sdtout
Cron().schedule(
# Turn of logging for job that runs every five seconds
Tab(name='my_fast_job', verbose=False).every(seconds=5).run(my_job, 'fast', seconds=5),

# Go ahead and let this job emit logging messages
Tab(name='my_slow_job').every(seconds=20).run(my_job, 'slow', seconds=20),
).go()

```

### Schedule future job to run repeatedly for a fixed amount of time
```python
from crontabs import Cron, Tab
from datetime import datetime


def my_job(*args, **kwargs):
print('args={} kwargs={} running at {}'.format(args, kwargs, datetime.now()))


Cron().schedule(
Tab(
name='future_job'
).every(
seconds=5
).starting_at(
'12/27/2017 16:45' # This argument can either be parsable text or datetime object.
).run(
my_job, 'fast', seconds=5
)
# max_seconds starts from the moment go is called. Pad for future run times accordingly.
).go(max_seconds=60)
```

# Run test suite with
```bash
git clone git@github.com:robdmc/crontabs.git
cd crontabs
pip install -e .[dev]
py.test -s --cov -n 8
```