A simple introduction to PiCloud presented to the PyAtl: Atlanta Python Programmers at their monthly Meetup on August 9, 2012

1. Introduction to
PiCloud
Bill Koch
@wekoch
kochwe@gmail.com

2. What is PiCloud?
An elastic compute cloud that can be
accessed directly within your Python code.

3. What is PiCloud?

4. What is PiCloud?
Simple Code
>>> import cloud
>>> job_id = cloud.call(lambda: 3*3)
>>> cloud.result(job_id)
9

5. Architecture Overview

6. Features of PiCloud
1. Compute Jobs
2. Crons
3. REST APIs
4. Realtime Cores,
Environments and Analytics

7. Compute Jobs Basic
>>> import cloud
>>> def domath(x,y):
return x + y
>>> job_id = cloud.call(domath, 2, 45)
>>> returned_value = cloud.result(job_id)
>>> print returned_value
47
>>> job_id
480

8. Understanding
Jobs
1.Created by cloud.call, Cron or
REST API calls
2.Functions are serialized via
custom pickle module call
cloudpickle (open sourced)
3.Modules are transmitted when
necessary

9. Data Flow of
Jobs
1.Programming model is
functionally based
2.Data is transmitted via
arguments and return values
3.Data cannot be accessed
between jobs
4.Jobs can spawn other jobs

10. Jobs

11. Compute Jobs

12. Creating a Child Proc
>>> def spawnnew(x, y):
s=x+y
z = 15
child_id = cloud.call(spawnedkid, s, z)
cloud.join(child_id)
r = cloud.result(child_id)
return s + r
>>> def spawnedkid(a, b):
return a + b
>>> x=9
>>> y=8
>>> jid = cloud.call(spawnnew, x, y)
>>> cloud.result(487)
49

13. Crons
•Runs a registered function at scheduled times.
•Utilizes the BSD-style cron timestamp found in *nix
•Cron jobs are created utilizing cloud.cron.register

14. Crons
>>> import httplib
>>> def sitepinger():
url = ‘python.org’
try:
conn = httplib.HTTPConnection(url)
conn.request("GET", '/')
r1 = conn.getresponse()
http_resp = "Content-Type: text/htmln" + """ %s %s %s """ % (url, str(r1.status), r1.reason)
except:
http_resp = "Content-Type: text/htmln" + """ Cannot connect to %s, site might be offline""" % (url)
return http_resp
>>> cloud.cron.register(sitepinger, 'sitepinger.v2', '0-59 * * * *')
>>> cloud.cron.info('sitepinger.v2')
{u'core_type': u'c1', u'schedule': u'0-59 * * * *', u'last_jid': 468, u'func_name': u'__main__.sitepinger at
<pyshell#26>:1', u'created': u'2012-08-09 15:06:03', u'last_run': u'2012-08-09 15:15:04', u'label':
u'sitepinger.v2', u'creator_host': u'mymainbox.local'}
>>> cloud.result(cloud.cron.info('sitepinger.v2')['last_jid'])
'Content-Type: text/htmln python.org 200 OK '
>>> cloud.cron.deregister('sitepinger.v2')

15. REST API

16. REST API
>>> def sub(x, y):
"""This is a function that subtracts!!"""
if x>y:
return x-y
else:
return y-x
>>> cloud.rest.publish(sub, 'subtraction')
u'https://api.picloud.com/r/251/subtraction'
mymainbox:~ bkoch$ curl -k -u $key:$secretkey https://api.picloud.com/r/251/
subtraction -d x=28 -d y=7
{"jid": 486}
>>> cloud.result(486)
21

17. Resources
• PiCloud - http://picloud.com
• Package List 2.7 - http://www.picloud.com/
docs/base_environment/2/installed/

18. Questions or
Comments?