bad security practices in getting started

[Matt Verran]

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-----------------------------------
Release: 0.1 on 2017-09-14 19:40
SHA: 8fa4937999220a9b493fd12dd488d9516a6e708f
Source: https://git.openstack.org/cgit/openstack/api-site/tree/doc/source/getting_started.rst
URL: https://developer.openstack.org/firstapp-libcloud/getting_started.html

In the spirit of contributing something while my other bug around the getting started project is considered its been a bugbear of mine to see a new tutorial advocating hardcoding the credentials into code (which may then be checked into a public repo on github/bitbucket etc).

Instead of...

# step-1
from libcloud.compute.types import Provider
from libcloud.compute.providers import get_driver

auth_username = 'your_auth_username'
auth_password = 'your_auth_password'
auth_url = 'http://controller:5000'
project_name = 'your_project_name_or_id'
region_name = 'your_region_name'

provider = get_driver(Provider.OPENSTACK)
conn = provider(auth_username,
                auth_password,
                ex_force_auth_url=auth_url,
                ex_force_auth_version='2.0_password',
                ex_tenant_name=project_name,
                ex_force_service_region=region_name)

How about suggesting

# step-1
import os
from libcloud.compute.types import Provider
from libcloud.compute.providers import get_driver

def get_env_var(name):
    if name in os.environ:
        return os.environ[name]
    else:
        prompt_text = "{0} was not set, maybe you haven't set your Openstack credentials?\nEnter a value for {0}: ".format(name)
        temp = raw_input(prompt_text)
        return temp

auth_username = get_env_var("OS_USERNAME")
auth_password = get_env_var("OS_PASSWORD")
auth_url = get_env_var("OS_AUTH_URL")
auth_url = auth_url.rsplit("/",1)[0]
project_name = get_env_var("OS_PROJECT_NAME")
region_name = get_env_var("OS_REGION_NAME")

provider = get_driver(Provider.OPENSTACK)
conn = provider(auth_username,
                auth_password,
                ex_force_auth_url=auth_url,
                ex_force_auth_version='2.0_password',
                ex_tenant_name=project_name,
                ex_force_service_region=region_name)

I'm not great at python so maybe a more pythonesque solution is possible but this certainly worked well enough for me and would encourage more secure default behaviour.