OpenShift PaaS platform from Redhat

We've looked before at AppFog PaaS platform that is leveraging CloudFoundry and Openstack. Today we will investigate the Redhat PaaS alternative, namely OpenShift.

What is OpenShift

OpenShift is a Platform as a Service solution according the the cloud systems taxonomy. It offers a solution, a software development platform that facilitates easy and rapid application development in the cloud.

It can provide a preintegrated software stack environment and can leverage IaaS providers for the virtual infrastructure management (How to Deploy OpenShift Enterprise on Red Hat OpenStack).

A comprehensive presentation that provide further details can be found here: http://rhsummit.files.wordpress.com/2013/06/noceda_t_0120_consumepaasinthecloudwithopenshift.pdf

Demo

• Sign in for free account on https://openshift.redhat.com
• Login and from "My App" tab create new application by selecting "Add Application ..." button.
• I've used as simple Python app based on CherryPy framework. 
• Once your gear (a Openshift name for your app container) is created you can take a look at the hello world code 
• To modify the source code clone the git repo. You will need to first register your public key.
• Generate a new ssh key pair.

$  ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/rado/.ssh/id_rsa): /tmp/tmp.key

$ ssh-agent | tee -a agent.sh
SSH_AUTH_SOCK=/tmp/ssh-pMmGGPP15635/agent.15635; export SSH_AUTH_SOCK;
SSH_AGENT_PID=15636; export SSH_AGENT_PID;
echo Agent pid 15636;

$source agent.sh
$ssh-add tmp.key
Identity added: tmp.key (tmp.key)

• Clone your source repo to modify your app source code.

$ git clone ssh://52c499a1e0b8cdda0f000016@rado-rado1stapp.rhcloud.com/~/git/rado.git/
Cloning into 'rado'...
remote: Counting objects: 62, done.
remote: Compressing objects: 100% (41/41), done.
remote: Total 62 (delta 16), reused 62 (delta 16)
Receiving objects: 100% (62/62), 18.93 KiB, done.
Resolving deltas: 100% (16/16), done.

• Modify the code to personalize it.

$cd rado/

$ find  | grep -v git
./.openshift
./.openshift/markers
./.openshift/action_hooks
./.openshift/action_hooks/README.md
./.openshift/cron
./.openshift/cron/minutely
./.openshift/cron/monthly
./.openshift/cron/weekly
./.openshift/cron/weekly/chrono.dat
./.openshift/cron/weekly/chronograph
./.openshift/cron/weekly/jobs.deny
./.openshift/cron/weekly/README
./.openshift/cron/weekly/jobs.allow
./.openshift/cron/README.cron
./.openshift/cron/daily
./.openshift/cron/hourly
./README.md
./LICENSE
./data
./libs
./wsgi
./wsgi/static
./wsgi/static/README
./wsgi/application
./app.py.disabled
./setup.py

$vim ./wsgi/application
$ cat wsgi/application
import sys
sys.stdout = sys.stderr

import atexit
import threading
import cherrypy

cherrypy.config.update({'environment': 'embedded'})

if cherrypy.__version__.startswith('3.0') and cherrypy.engine.state == 0:
    cherrypy.engine.start(blocking=False)
    atexit.register(cherrypy.engine.stop)

class Root(object):
    def index(self):
        return 'Hello from rado 1st app on openshift ;)!'
    index.exposed = True

application = cherrypy.Application(Root(), script_name=None, config=None)

• Once you are happy with t he code it is time to push changes back to git and redeploy it inside OpenShift.

$ git commit ./wsgi/application
[master 0eccd4d] init
 1 file changed, 1 insertion(+), 1 deletion(-)

$ git push origin master
Counting objects: 7, done.
Compressing objects: 100% (4/4), done.
Writing objects: 100% (4/4), 393 bytes, done.
Total 4 (delta 2), reused 0 (delta 0)
remote: Stopping PYTHON cart
remote: [Wed Jan 01 17:59:08 2014] [warn] PassEnv variable SHELL was undefined
remote: [Wed Jan 01 17:59:08 2014] [warn] PassEnv variable USER was undefined
remote: [Wed Jan 01 17:59:08 2014] [warn] PassEnv variable LOGNAME was undefined
remote: Waiting for stop to finish
remote: Building git ref 'master', commit 0eccd4d
remote: running develop
remote: running egg_info
remote: creating Example_CherryPy.egg-info
remote: writing requirements to Example_CherryPy.egg-info/requires.txt
remote: writing Example_CherryPy.egg-info/PKG-INFO
remote: writing top-level names to Example_CherryPy.egg-info/top_level.txt
remote: writing dependency_links to Example_CherryPy.egg-info/dependency_links.txt
remote: writing requirements to Example_CherryPy.egg-info/requires.txt
remote: writing Example_CherryPy.egg-info/PKG-INFO
remote: writing top-level names to Example_CherryPy.egg-info/top_level.txt
remote: writing dependency_links to Example_CherryPy.egg-info/dependency_links.txt
remote: writing manifest file 'Example_CherryPy.egg-info/SOURCES.txt'
remote: reading manifest file 'Example_CherryPy.egg-info/SOURCES.txt'
remote: writing manifest file 'Example_CherryPy.egg-info/SOURCES.txt'
remote: running build_ext
remote: Creating /var/lib/openshift/52c499a1e0b8cdda0f000016/app-root/runtime/dependencies/python/virtenv/lib/python2.7/site-packages/Example-CherryPy.egg-link (link to .)
remote: Example-CherryPy 1.0 is already the active version in easy-install.pth
remote:
remote: Installed /var/lib/openshift/52c499a1e0b8cdda0f000016/app-root/runtime/repo
remote: Processing dependencies for Example-CherryPy==1.0
remote: Searching for CherryPy==3.2.4
remote: Best match: CherryPy 3.2.4
remote: Processing CherryPy-3.2.4-py2.7.egg
remote: CherryPy 3.2.4 is already the active version in easy-install.pth
remote: Installing cherryd script to /var/lib/openshift/52c499a1e0b8cdda0f000016/python/virtenv/bin
remote:
remote: Using /var/lib/openshift/52c499a1e0b8cdda0f000016/app-root/runtime/dependencies/python/virtenv/lib/python2.7/site-packages/CherryPy-3.2.4-py2.7.egg
remote: Finished processing dependencies for Example-CherryPy==1.0
remote: Script /var/lib/openshift/52c499a1e0b8cdda0f000016/python//virtenv/bin/activate.fish cannot be made relative (it's not a normal script that starts with #!/var/lib/openshift/52c499a1e0b8cdda0f000016/python/virtenv/bin/python)
remote: Script /var/lib/openshift/52c499a1e0b8cdda0f000016/python//virtenv/bin/activate.csh cannot be made relative (it's not a normal script that starts with #!/var/lib/openshift/52c499a1e0b8cdda0f000016/python/virtenv/bin/python)
remote: Preparing build for deployment
remote: Deployment id is f17888e7
remote: Activating deployment
remote: Script /var/lib/openshift/52c499a1e0b8cdda0f000016/python//virtenv/bin/activate.fish cannot be made relative (it's not a normal script that starts with #!/var/lib/openshift/52c499a1e0b8cdda0f000016/python/virtenv/bin/python)
remote: Script /var/lib/openshift/52c499a1e0b8cdda0f000016/python//virtenv/bin/activate.csh cannot be made relative (it's not a normal script that starts with #!/var/lib/openshift/52c499a1e0b8cdda0f000016/python/virtenv/bin/python)
remote: Starting PYTHON cart
remote: Result: success
remote: Activation status: success
remote: Deployment completed with status: success

• Final test that all worked fine ;)

$ curl -v -s http://rado-rado1stapp.rhcloud.com ;echo
* About to connect() to rado-rado1stapp.rhcloud.com port 80 (#0)
*   Trying 54.221.76.112... connected
> GET / HTTP/1.1
> User-Agent: curl/7.22.0 (x86_64-pc-linux-gnu) libcurl/7.22.0 OpenSSL/1.0.1 zlib/1.2.3.4 libidn/1.23 librtmp/2.3
> Host: rado-rado1stapp.rhcloud.com
> Accept: */*
>
< HTTP/1.1 200 OK
< Date: Wed, 01 Jan 2014 23:33:20 GMT
< Server: Apache/2.2.22 (Red Hat Enterprise Web Server)
< Content-Length: 40
< Content-Type: text/html;charset=utf-8
< Vary: Accept-Encoding
<
* Connection #0 to host rado-rado1stapp.rhcloud.com left intact
* Closing connection #0

Hello from rado 1st app on openshift ;)!

Quick overview of AppFog PaaS platform

There is Openstack that aims to provide opensource IaaS solution for the Internet. But cloud has many faces and in a simplistic cloud taxonomy we can speak of IaaS, PaaS and SaaS as the main trends in the industry.

The video below provide a short introduction and comparison of Openstack and Appfog that is based on CloudFoundry. Both products embracing the open source developed paradigm. Both try to define standard and become leader in the respective domain.

As a bonus material for these who are interested in the overall technical system architecture this link  provide slides and video of Derek Collison (a lead technical architect for CloudFondry at Vmware) Cloud Foundry: Inside the Machine

Demonstration and example

1. You need to create a basic account that is free (but has resource limitation)
2. You can use the GUI to create your fist application
3. Use the CLI af (docu here) to get a look and feel what it is 

This is the automatically generated demo.

 
$ curl -v http://rado-python.hp.af.cm/
* About to connect() to rado-python.hp.af.cm port 80 (#0)
*   Trying 15.185.166.79... connected
> GET / HTTP/1.1
> User-Agent: curl/7.22.0 (i686-pc-cygwin) libcurl/7.22.0 OpenSSL/0.9.8r zlib/1.2.5 libidn/1.22 libssh2/1.2.7
> Host: rado-python.hp.af.cm
> Accept: */*
>
< HTTP/1.1 200 OK
< Server: nginx
< Content-Type: text/plain
< Keep-Alive: timeout=300
< Content-Length: 34
< Accept-Ranges: bytes
< Date: Thu, 28 Mar 2013 01:25:30 GMT
< X-Varnish: 816993201
< Age: 0
< Via: 1.1 varnish
< Connection: keep-alive
<
* Connection #0 to host rado-python.hp.af.cm left intact
* Closing connection #0
Hello World! AppFog Python Support

Some info about the application hosted on AppFog.

 
C:\Users\radoslaw>af login
Attempting login to [https://api.appfog.com]
Email: xxx
Password: ************
Successfully logged into [https://api.appfog.com]

C:\Users\radoslaw>af info
AppFog Free Your Cloud Edition
For support visit http://support.appfog.com

Target:   https://api.appfog.com (v0.999)
Client:   v0.3.18.12

User:     xxx
Usage:    Memory   (384.0M of 2.0G total)
          Services (1 of 8 total)
          Apps     (2 of 9999 total)

# download the source code 
C:\Users\radoslaw\workspace\appfog>af pull rado-python
Pulling last pushed source code: OK

The source code for our fist hello word application is very simple.

 
import bottle
import os

def application(environ, start_response):
    data = "Hello World! AppFog Python Support"
    start_response("200 OK", [
            ("Content-Type", "text/plain"),
            ("Content-Length", str(len(data)))
            ])
    return iter([data])

By default only one instance (cloud server?) is spin up to host our app.

 
C:\Users\radoslaw\workspace\appfog>af stats rado-python

+----------+-------------+----------------+--------------+---------------+
| Instance | CPU (Cores) | Memory (limit) | Disk (limit) | Uptime        |
+----------+-------------+----------------+--------------+---------------+
| 0        | 0% (4)      | 26.1M (128M)   | 7.1M (1G)    | 0d:0h:58m:18s |
+----------+-------------+----------------+--------------+---------------+

C:\Users\radoslaw\workspace\appfog>af instances rado-python

+-------+---------+--------------------+
| Index | State   | Start Time         |
+-------+---------+--------------------+
| 0     | RUNNING | 03/28/2013 12:34AM |
+-------+---------+--------------------+

On the GUI we can quickly and easily increase the number of instance. Once new instance is spun up and application code is cloned to it we see the changes on the CLI as well.

 
C:\Users\radoslaw\workspace\appfog>af stats rado-python

+----------+-------------+----------------+--------------+--------------+
| Instance | CPU (Cores) | Memory (limit) | Disk (limit) | Uptime       |
+----------+-------------+----------------+--------------+--------------+
| 0        | 0% (4)      | 26.1M (128M)   | 7.1M (1G)    | 0d:1h:2m:35s |
| 1        | 0.7% (4)    | 26.0M (128M)   | 0B (1G)      | 0d:0h:0m:58s |
+----------+-------------+----------------+--------------+--------------+

C:\Users\radoslaw\workspace\appfog>af instances rado-python

+-------+---------+--------------------+
| Index | State   | Start Time         |
+-------+---------+--------------------+
| 0     | RUNNING | 03/28/2013 12:34AM |
| 1     | RUNNING | 03/28/2013 01:35AM |
+-------+---------+--------------------+

After the testing we delete our application.

 
C:\Users\radoslaw\workspace\appfog>af delete rado-python

References

1. https://docs.appfog.com/getting-started/af-cli#max-os-x-linux
2. http://blog.appfog.com/getting-started-with-appfogs-command-line/
3. http://net.tutsplus.com/articles/editorials/appfog-vs-heroku/