This guide will walk you through deploying a Python Django CRUD application on Deis.
If you do not yet have a controller or a Deis formation, please review the Deis installation instructions.
gem command on your workstationgem install foremanIf you want to use an existing application, no problem. You can also use the Deis sample application located at https://github.com/bengrunfeld/example-python-django-crud-app. Clone the example application to your local workstation:
$ git clone git@github.com:bengrunfeld/example-python-django-crud-app.git.git
$ cd example-python-django-crud-appTo use a Python application with Deis, you will need to conform to 3 basic requirements:
If you're deploying the example application, it already conforms to these requirements.
Pip requires that you explicitly declare your dependencies using a requirements.txt file. Here is a very basic example:
Django==1.6
dj-database-url==0.2.2
dj-static==0.0.5
gunicorn==18.0
psycopg2==2.5.1
static==0.4We highly recommend isolating your dependencies inside a Python virtualenv:
$ virtualenv venv # create the virtualenv
New python executable in venv/bin/python
Installing setuptools............done.
Installing pip...............done.
$ source venv/bin/activate # activate the virtualenvYou can then install dependencies on your local workstation with pip install -r requirements.txt:
(venv)$ pip install -r requirements.txt
Downloading/unpacking dj-static==0.0.5 (from -r requirements.txt (line 3))
Downloading dj-static-0.0.5.tar.gz
Running setup.py egg_info for package dj-staticDeis relies on a Foreman Procfile that lives in the root of your repository. This is where you define the command(s) used to run your application. Here is an example Procfile:
web: gunicorn django_crud_app.wsgiThis tells Deis to run web workers using the command gunicorn django_crud_app.wsgi. You can test this locally by running foreman start.
(venv)$ foreman startYou should now be able to access your application locally at http://localhost:5000.
Deis uses environment variables to manage your application's configuration, especially database configuration. For example, the following are used to connect your Django app to an Amazon RDS Instance.
DJ_ENGINE: postgresql_psycopg2
DJ_PASS: somepass
DJ_USER: someuser
DJ_HOST: id.somehost.us-west-2.rds.amazonaws.com
DJ_NAME: somedb
DJ_PORT: 5432Per the prerequisites, we assume you have access to an existing Deis formation. If not, please review the Deis installation instuctions.
Use the following command to create an application on an existing Deis formation.
$ deis create --formation=<formationName> --id=<appName>
Creating application... done, created <appName>
Git remote deis addedIf an ID is not provided, one will be auto-generated for you.
Use git push deis master to deploy your application.
$ git push deis master
Counting objects: 65, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (40/40), done.
Writing objects: 100% (65/65), 15.95 KiB, done.
Total 65 (delta 19), reused 61 (delta 18)
Python app detected
-----> No runtime.txt provided; assuming python-2.7.4.
-----> Preparing Python runtime (python-2.7.4)Once your Django application has been deployed, you will need to sync the database before you can open it. To do this, run deis run 'python manage.py syncdb'.
You can then use deis open to view it in a browser. To find out more info about your application, use deis info.
To scale your application's Docker containers, use deis scale and specify the number of containers for each process type defined in your application's Procfile. For example, deis scale web=8.
$ deis scale web=8
Scaling containers... but first, coffee!
done in 16s
=== <appName> Containers
--- web: `gunicorn django_crud_app.wsgi`
web.1 up 2013-12-12T23:04:56.242Z (dev2-runtime-1)
web.2 up 2013-12-13T18:23:26.635Z (dev2-runtime-1)
web.3 up 2013-12-13T18:23:26.653Z (dev2-runtime-1)
web.4 up 2013-12-13T18:23:26.668Z (dev2-runtime-1)
web.5 up 2013-12-13T18:23:26.684Z (dev2-runtime-1)
web.6 up 2013-12-13T18:23:26.699Z (dev2-runtime-1)
web.7 up 2013-12-13T18:23:26.714Z (dev2-runtime-1)
web.8 up 2013-12-13T18:23:26.731Z (dev2-runtime-1)Deis applications are configured using environment variables. To connect to a 3rd-party database like Amazon RDS, you'll need to set your login credentials using environment variables.
$ deis config:set DJ_NAME=notesdb
=== <appName>
DJ_USER: opuser
DJ_PASS: thispassword
DJ_NAME: notesdb
DJ_HOST: dbid.somehost.us-west-2.rds.amazonaws.com
DJ_PORT: 5432
DJ_ENGINE: postgresql_psycopg2deis config:set is also how you connect your application to other backing services like queues and caches. You can use deis run to execute one-off commands against your application for things like database administration, initial application setup and inspecting your container environment. deis run env will return all of your environment variables that have been set in Deis.
$ deis run ls -la
total 60
drwxr-xr-x 6 root root 4096 Dec 12 23:04 .
drwxr-xr-x 69 root root 4096 Dec 13 18:30 ..
-rw-rw-r-- 1 root root 26 Dec 12 22:11 .gitignore
drwxr-xr-x 3 root root 4096 Dec 12 23:03 .heroku
drwxr-xr-x 2 root root 4096 Dec 13 18:26 .profile.d
-rw-r--r-- 1 root root 57 Dec 12 23:04 .release
-rw-r--r-- 1 root root 35 Dec 12 23:04 Procfile
-rw-r--r-- 1 root root 826 Dec 12 23:04 README.md
drwxr-xr-x 2 root root 4096 Dec 13 18:26 django_crud_app
-rw-r--r-- 1 root root 258 Dec 12 23:04 manage.py
drwxr-xr-x 4 root root 4096 Dec 12 23:04 notes
-rw-r--r-- 1 root root 94 Dec 12 23:04 requirements.txt
-rw-r--r-- 1 root root 13 Dec 12 23:04 runtime.txtTo view your application's log output, including any errors or stack traces, use deis logs.
$ deis logs
Dec 13 18:27:28 ip-172-31-28-70 djangoapp[web.7]: 2013-12-13 18:27:28 [13] [INFO] Using worker: sync
Dec 13 18:27:28 ip-172-31-28-70 djangoapp[web.7]: 2013-12-13 18:27:28 [18] [INFO] Booting worker with pid: 18
Dec 13 18:27:39 ip-172-31-28-70 djangoapp[web.8]: 2013-12-13 18:27:39 [14] [INFO] Starting gunicorn 18.0
Dec 13 18:27:39 ip-172-31-28-70 djangoapp[web.8]: 2013-12-13 18:27:39 [14] [INFO] Listening at: http://0.0.0.0:10008 (14)