http://stackoverflow.com/questions/28702673/loading-global-data-for-server-using-flask-and-gunicorn

app_factory.py

import os

from flask import Flask, Blueprint, g

api = Blueprint('api', __name__)

class Server(object):
   def __init__(self, data):
       self.data = data

@api.route("/api_method", methods=['GET', 'POST'])
def api_method():
    return g.server.data

def make_app():
    '''
    Application factory: http://flask.pocoo.org/docs/0.10/patterns/appfactories/
    '''
    app = Flask(__name__)
    app.register_blueprint(api)

    with open(os.environ['SERVER_FILE']) as f:
        server = Server(f.read())

    @app.before_request
    def add_server_to_globals():
        g.server = server

    return app

if __name__ == '__main__':
    app = make_app()
    app.config['DEBUG'] = True
    app.run(use_debugger=True, use_reloader=True)

app_gunicorn.py

from app_factory import make_app
app = make_app()

app_simple.py

import os

from flask import Flask, g

app = Flask(__name__)

class Server(object):
   def __init__(self, data):
       self.data = data

@app.route("/api_method", methods=['GET', 'POST'])
def api_method():
    return g.server.data

@app.before_request
def add_server_to_globals():
    with open(os.environ['SERVER_FILE']) as f:
        g.server = Server(f.read())

if __name__ == '__main__':
    app.run()

output.txt

$ SERVER_FILE=app.py bin/gunicorn app_simple:app
[2015-02-24 10:10:20 -0800] [3217] [INFO] Starting gunicorn 19.2.1
[2015-02-24 10:10:20 -0800] [3217] [INFO] Listening at: http://127.0.0.1:8000 (3217)
[2015-02-24 10:10:20 -0800] [3217] [INFO] Using worker: sync
[2015-02-24 10:10:20 -0800] [3220] [INFO] Booting worker with pid: 3220
...

OR if you use the application factory:

$ SERVER_FILE=app.py bin/gunicorn app_gunicorn:app
[2015-02-25 09:52:29 -0800] [5613] [INFO] Starting gunicorn 19.2.1
...

$ curl http://127.0.0.1:8000/api_method
import os

from flask import Flask, g

app = Flask(__name__)
...