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 ;)!
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