Python 那些事儿 (三)

Try to deploy a flask demo app

this is the app structure:

.
├── flaskdemo1
│   ├── flaskr.py
│   ├── flaskr_tests.py
│   ├── __init__.py
│   ├── README
│   ├── schema.sql
│   ├── static
│   │   └── style.css
│   └── templates
│       ├── layout.html
│       ├── login.html
│       └── show_entries.html
└── flaskdemo1.wsgi

so the file flaskdemp1.wsgi is the entry point for this app.
let us check what says in this script file:

#!/home/matt/env1/bin/python2.7
import sys
import os
import site
import logging
logging.basicConfig(stream=sys.stderr)

site.addsitedir('~/env1/lib/python2.7/site-packages')
sys.path.insert(0,"/var/www/flaskdemo1/")
# above lines they just prepare the environments.

# this line is to load flaskr app as a entrypoint
from flaskdemo1.flaskr import app as application

.
├── flaskdemo1
│   ├── flaskr.py
│   ├── flaskr_tests.py
│   ├── __init__.py
│   ├── README
│   ├── schema.sql
│   ├── static
│   │   └── style.css
│   └── templates
│       ├── layout.html
│       ├── login.html
│       └── show_entries.html

here, this is a complete flask app, firstly let add a __init__.py file to make this folder as a module. so that we can load this app as a module in the wsgi file:

from flaskdemo1.flaskr import app as application

so, at here, we can start this flask app rightly with apache+mod_wsgi.
but, when we do open the domain of this app in browser, what's happening in the app internal? let us dig this point.