部署 Django 到 Heroku - Note for Richo

前言

總算是買了自己的域名 richo.tw ，有趣的是韓政憲.tw跟韓政憲.台灣竟然被買走了...可惡的線上名片網站= =+
要來找免費的虛擬主機，用Django查到有人推薦Heroku，看到界面風格忍不住就用了XD

前置作業

+Python
+Virtualenv, see guide
+Postgres
+申請Heroku帳號

建立Virtualenv

先建立最外層的project資料夾

$ mkdir hellodjango && cd hellodjango

建立及啟動虛擬環境

$ virtualenv venv  
$ source venv/bin/activate

接著用pip裝application的dependencies，其中要裝的是django-toolbelt，包含：
+Django (the web framework)
+Gunicorn (WSGI server)
+dj-database-url (a Django configuration helper)
+dj-static (a Django static file server)

$ pip install django-toolbelt  
Installing collected packages: Django, psycopg2, gunicorn, dj-database-url, dj-static, static  
    ...  
Successfully installed Django psycopg2 gunicorn dj-database-url dj-static static  
Cleaning up...

建立Django appilcation
P.S.別忘記最後的那個「.」

django-admin.py startproject hellodjango .

用Procfile宣告process type

在application的root目錄建立Procfile，加入：

web: gunicorn hellodjango.wsgi

接著執行

$ foreman start  
2013-04-03 16:11:22 [8469] [INFO] Starting gunicorn 0.17.2  
2013-04-03 16:11:22 [8469] [INFO] Listening at: http://127.0.0.1:8000 (8469)

用Pip指定dependencies

$ pip freeze > requirements.txt

它會製作出requirements.txt，內含：

Django==1.6  
dj-database-url==0.2.2  
dj-static==0.0.5  
gunicorn==18.0  
psycopg2==2.5.1  
static==0.4  
wsgiref==0.1.2

Django設定

將以下內容加入setting.py

# Parse database configuration from $DATABASE_URL  
import dj_database_url  
DATABASES['default'] =  dj_database_url.config()

# Honor the 'X-Forwarded-Proto' header for request.is_secure()  
SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')

# Allow all host headers  
ALLOWED_HOSTS = ['*']

# Static asset configuration  
import os  
BASE_DIR = os.path.dirname(os.path.abspath(__file__))  
STATIC_ROOT = 'staticfiles'  
STATIC_URL = '/static/'

STATICFILES_DIRS = (  
    os.path.join(BASE_DIR, 'static'),  
)

將以下內容加入wsgi.py

from django.core.wsgi import get_wsgi_application  
from dj_static import Cling

application = Cling(get_wsgi_application())

Git

建立.gitignore，寫入：

venv  
*.pyc  
staticfiles

建立新的git repository來存放application

$ git init  
Initialized empty Git repository in /Users/kreitz/hellodjango/.git/  
$ git add .  
$ git commit -m "my django app"  
[master (root-commit) 2943412] my django app  
 7 files changed, 230 insertions(+)  
 create mode 100644 .gitignore  
 create mode 100644 Procfile  
 create mode 100644 hellodjango/__init__.py  
 create mode 100644 hellodjango/settings.py  
 create mode 100644 hellodjango/urls.py  
 create mode 100644 hellodjango/wsgi.py  
 create mode 100644 manage.py  
 create mode 100644 requirements.txt

Deploy到Heroku

先用Heroku指令建立新專案

$ heroku create  
Creating simple-spring-9999... done, stack is cedar  
http://simple-spring-9999.herokuapp.com/ | git@heroku.com:simple-spring-9999.git  
Git remote heroku added

用git push來deploy application

$ git push heroku master  
Counting objects: 11, done.  
Delta compression using up to 4 threads.  
Compressing objects: 100% (9/9), done.  
Writing objects: 100% (11/11), 4.01 KiB, done.  
Total 11 (delta 0), reused 0 (delta 0)  
-----> Python app detected  
-----> No runtime.txt provided; assuming python-2.7.6.  
-----> Preparing Python runtime (python-2.7.6)  
-----> Installing Distribute (0.6.36)  
-----> Installing Pip (1.3.1)  
-----> Installing dependencies using Pip (1.3.1)  
       Downloading/unpacking Django==1.5 (from -r requirements.txt (line 1))  
       ...  
       Successfully installed Django psycopg2 gunicorn dj-database-url dj-static static  
       Cleaning up...  
-----> Collecting static files  
       0 static files copied.

-----> Discovering process types  
       Procfile declares types -> web

-----> Compiled slug size is 29.5MB  
-----> Launching... done, v6  
       http://simple-spring-9999.herokuapp.com deployed to Heroku

To git@heroku.com:simple-spring-9999.git  
* [new branch]      master -> master

Dyno設定

確保至少一個dyno在跑，執行

$ heroku ps:scale web=1

下面指令可用來check dyno的status：

$ heroku ps  
=== web: `gunicorn hellodjango.wsgi`  
web.1: up for 10s

要用瀏覽器開啟app，直接執行：

$ heroku open  
Opening simple-spring-9999.herokuapp.com... done

查看log：

heroku logs

之後要跑Django指令，直接在前面加上heroku run：

$ heroku run python manage.py syncdb  
Running python manage.py syncdb attached to terminal... up, run.1  
Creating tables ...  
Creating table auth_permission  
Creating table auth_group_permissions  
Creating table auth_group  
Creating table auth_user_groups  
Creating table auth_user_user_permissions  
Creating table auth_user  
Creating table django_content_type  
Creating table django_session  
Creating table django_site

You just installed Django's auth system, which means you don't   have any superusers defined.  
Would you like to create one now? (yes/no): yes  
Username (leave blank to use 'u53976'): kenneth  
Email address: kenneth@heroku.com  
Password:  
Password (again):  
Superuser created successfully.  
Installing custom SQL ...  
Installing indexes ...  
Installed 0 object(s) from 0 fixture(s)

使用Django shell

$ heroku run python manage.py shell  
Running python manage.py shell attached to terminal... up, run.1  
Python 2.7.6 (default, Jan 16 2014, 02:39:37)  
[GCC 4.4.3] on linux2  
Type "help", "copyright", "credits" or "license" for more   information.  
(InteractiveConsole)  
>>> from django.contrib.auth.models import User  
>>> User.objects.all()  
[<User: kenneth>]

大功告成！

Reference

+Getting Started with Django on Heroku