I set an environment variable that I want to access in my Python application. How do I get its value?
Actually it can be done this away:
import os
for item, value in os.environ.items():
print('{}: {}'.format(item, value))
Or simply:
for i, j in os.environ.items():
print(i, j)
For view the value in the parameter:
print(os.environ['HOME'])
Or:
print(os.environ.get('HOME'))
To set the value:
os.environ['HOME'] = '/new/value'
Environment variables are accessed through os.environ
import os
print(os.environ['HOME'])
Or you can see a list of all the environment variables using:
os.environ
As sometimes you might need to see a complete list!
# using get will return `None` if a key is not present rather than raise a `KeyError`
print(os.environ.get('KEY_THAT_MIGHT_EXIST'))
# os.getenv is equivalent, and can also give a default value instead of `None`
print(os.getenv('KEY_THAT_MIGHT_EXIST', default_value))
Python default installation on Windows is C:\Python
. If you want to find out while running python you can do:
import sys
print(sys.prefix)
If you are planning to use the code in a production web application code,
using any web framework like Django/Flask, use projects like envparse, using it you can read the value as your defined type.
from envparse import env
# will read WHITE_LIST=hello,world,hi to white_list = ["hello", "world", "hi"]
white_list = env.list("WHITE_LIST", default=[])
# Perfect for reading boolean
DEBUG = env.bool("DEBUG", default=False)
NOTE: kennethreitz's autoenv is a recommended tool for making project specific environment variables, please note that those who are using autoenv
please keep the .env
file private (inaccessible to public)
You can also try this
First, install python-decouple
pip install python-decouple
import it in your file
from decouple import config
Then get the env variable
SECRET_KEY=config('SECRET_KEY')
Read more about the python library here
There's also a number of great libraries. Envs for example will allow you to parse objects out of your environment variables, which is rad. For example:
from envs import env
env('SECRET_KEY') # 'your_secret_key_here'
env('SERVER_NAMES',var_type='list') #['your', 'list', 'here']
.env File
Here is my .env file (I changed multiple characters in each key to prevent people hacking my accounts).
SECRET_KEY=6g18169690e33af0cb10f3eb6b3cb36cb448b7d31f751cde
AWS_SECRET_ACCESS_KEY=18df6c6e95ab3832c5d09486779dcb1466ebbb12b141a0c4
DATABASE_URL='postgres://drjpczkqhnuvkc:f0ba6afd133c53913a4df103187b2a34c14234e7ae4b644952534c4dba74352d@ec2-54-146-4-66.compute-1.amazonaws.com:5432/ddnl5mnb76cne4'
AWS_ACCESS_KEY_ID=AKIBUGFPPLQFTFVDVIFE
DISABLE_COLLECTSTATIC=1
EMAIL_HOST_PASSWORD=COMING SOON
MAILCHIMP_API_KEY=a9782cc1adcd8160907ab76064411efe-us17
MAILCHIMP_EMAIL_LIST_ID=5a6a2c63b7
STRIPE_PUB_KEY=pk_test_51HEF86ARPAz7urwyGw9xwLkgbgfCYT48LttlwjEkb88I7Ljb5soBtuKXBaPiKfuu0Cx2BzIowR3jJFkC8ybFBAEf00DFY46tB8
STRIPE_SECRET_KEY=sk_test_19HEF55BCEAz7urwytx7tO3QCxV4R8DEFXbqj6esg7OKuybiSTI8iJD8mmJUQpg4RKENxuS04DKOCzYHpDkAjUttO00LOmsT5Eg
settings
I was told my data was corrupted. I was struggling to work out what was going on. I had a suspicion the values from .env were not being passed into my settings file.
print(os.environ.get('AWS_SECRET_ACCESS_KEY'))
print(os.environ.get('AWS_ACCESS_KEY_ID'))
print(os.environ.get('AWS_SECRET_ACCESS_KEY'))
print(os.environ.get('DATABASE_URL'))
print(os.environ.get('SECRET_KEY'))
print(os.environ.get('DISABLE_COLLECTSTATIC'))
print(os.environ.get('EMAIL_HOST_PASSWORD'))
print(os.environ.get('MAILCHIMP_API_KEY'))
print(os.environ.get('MAILCHIMP_EMAIL_LIST_ID'))
print(os.environ.get('STRIPE_PUB_KEY'))
print(os.environ.get('STRIPE_SECRET_KEY'))
The only value being printed correctly was the SECRET_KEY. I reviewed the .env file and for the life of me could not see any reason why the SECRET_KEY was working and nothing else.
I got everything working eventually by putting this above the print statements.
from dotenv import load_dotenv #for python-dotenv method
load_dotenv() #for python-dotenv method
And doing
pip install -U python-dotenv
I am still not sure why SECRET_KEY was working when all the others were broken.