I am using python venv to create virtual environments. But, since I am working with several projects with different virtual environments, I don't want to manualy set environment variables every time I switch to a different project.
Is there a way to set venv environment variables automatically when activating the venv?
What is the best practice for this problem?
A good practice is to use dotenv. You can load your environment by placing your environment variables into a file named .env, and whenever you would like to load an environment, just use the lines:
from dotenv import load_dotenv
load_dotenv()
This has the nicety that it only exists within the scope of you running a single script, since it essentially works like calling os.environ['variable'] = 'value' a number of times.
Activating a virtual environment is nothing more than sourcing a shell script. You can edit that script to set whatever variables you like. You will probably also want to edit the definition of deactivate to clear or roll back whatever changes you made to the environment.
you need to write a bash scirpt (in case you are using bash shell), where you specified a particular command which will activate the project python environment and add the project specific envrionment variable in the system environment. and remove the environment variable when you exit the project python environment.
but i don't this is good/correct way to do things. #mz solution will be correct, where you define a .env file and define env variable in it. and use load_env to read the env variable when project runs
This concept is based on Two Scoops of Django. I have implemented it using venv.
Open the Windows PowerShell Script in your virtual environment generated by venv.
The script is located at venv/Scripts/Activate.ps1
At the bottom of the file, you will see this line of code:
$env:VIRTUAL_ENV = $VenvDir
Below that code, enter your environment variable as follow:
$env:VARIABLE_NAME = 'variable_value'
Same concept goes if you are using the Command Prompt to activate the environment, you will need to place environment variables in venv/Scripts/activate.bat
Related
I have created a virtual environment with pyenv virtualenv 3.5.9 projectname for developing a django project.
How can I set environment variables for my code to use?
I tried to add the environment variable DATABASE_USER in /Users/developer/.pyenv/versions/projectname/bin/activate
like this:
export DATABASE_USER="dbuser"
When I tried to echo $DATABASE_USER an empty string gets printed.
Tried to install zsh-autoenv
And now I can echo $DATABASE_USER and get the value set in the .autoenv.zsh file.
But I can't seem to get the environment variable to be available to my django code:
If I try to os.getenv('DATABASE_USER', '') in the python shell inside the virtualenv, I get ''
What could be wrong? Is the zsh-autoenv variables just available for the zsh shell and not python manage.py shell ?
I was wondering a similar thing, and I stumbled across a reddit thread where someone else had asked the same question, and eventually followed up noting some interesting finds.
As you noticed, pyenv doesn't seem to actually use the bin/activate file. They didn't say what the activation method is, but like you, adding environment variables there yielded no results.
In the end, they wound up installing autoenv, which bills itself as directory-based environments. It allows you to create an .env file in your directory, and when you cd to that directory, it runs the .env file. You can use it for environment variables, or you could add anything else to it.
I noticed on the autoenv page that they say you should probably use direnv instead, as it has better features and is higher quality software. Neither of these are Python or pyenv specific, and if you call your python code from outside of the directory, they may not work. Since you're using pyenv, you're probably running your code from within the directory anyway, so I think there's a good chance either one could work.
I'm completely new to this. I have set up Python3 and Atom and installed Hydrogen for Atom so I can run each line of my code and see the output.
I have set up a virtual environment and added packages to it.
My problem is that inside my Atom .py file, when I say import numpy as np for example, it tells me that the module is not found. So I think it is looking in some default place and not inside my virtual environment. Which makes sense as I don't know how to tell it to look inside the virtual environment.
I know that inside terminal I can load the virtual environment and then call the .py file from there and it will look in the right place. However that is not what I want to do. I want to be able to tell it to look in the virtual environment in the top line of the code and execute using Hydrogen, and then load the packages I want using Hydrogen, and then carry on with each line of code after that using Hydrogen.
Can someone tell me how to tell python to look in a specific virtual environment for the duration of the .py file that is being developed/executed?
For our purpose here virtual environments are just changing the search path of your interpreter.
Therefore if we want to search in a given virtual environment we can just add the path of this environment to our search path, which you can do in python by using
import sys
sys.path.append('/path/to/virtualenv')
The path to your virtual environment depends on how you configured it, but usually they are stored in a subfolder of your home directory called .virtualenvs, so this would probably look like
import sys
sys.path.append('/home/username/.virtualenvs/EnvName/')
# rest of code
Also note that this does not change your system path or pythonpath environment variables, and therefore only lasts for the duration of this python interpreter instance.
I have a ROS application which has a work space with a setup.bash file and another python script with its own virtual environment.
So far this is what I do in my terminal:
1_ pipenv shell (to activate my python virtual environment).
2_ source ../ros_workspace/devel/setup.bash
3_ python some_python_script.py
This code works as I expect.
However, I want to do the same and run this script in pycharm, where my virtual environment is already activated. But how do I source the setup bash additionaly?
My setup.bash file also looks like the following:
What I have tried also is making a "before launch" as follows:
If you set your virtual environment as your interpreter of choice in PyCharm, it will use that particular virtual environment to run its scripts. However, you can also take advantage of some of the functionality that our run configurations provide.
You can check out the "Before Launch" part of the whole configuration window to enter scripts that you want executed.
Once you've set your configurations, you can then go on to run or debug the configuration. Furthermore, if it is just environment variables that you want to source, you can just put in the environment variables in the "Environment Variables" box.
In case you want to run a shellscript, you will need to create a new shell configuration like so:
Once you've added that configuration, you can then go on to reference it later.
You will now see that you can reference that configuration in question:
I know that there is already a question similar to this,but i think the answer i wanted is not there.
I am new to django.i have created an virtual environment with virtualenv and a django project,but how can we know that my project is using the packages of virtual environment rather than using global packages??please give me some detailed answer.THANKS in advance.
you make sure you run /path/to/my_venv/bin/activate and your command shell prompt should look like (my_venv) C:\ > or (my_venv) /home/user$ or similar depending on your os
import sys
print(hasattr(sys, 'real_prefix') or sys.base_prefix != sys.prefix)
Try running above code. If False you are using global env and if True then virtual env.
One way is to use one of the IDEs to help you with that.
If you use PyCharm for example, it helps you with defining the virtual environment, and then when you open their terminal, it will be starting the venv for you.
https://www.jetbrains.com/help/pycharm/creating-and-running-your-first-django-project.html
If you run your commands from the command line/terminal, you need to activate the virtual environment first and then use the python from that venv.
https://developer.mozilla.org/en-US/docs/Python/Virtualenv
I usually create a venv folder inside the project root folder (next to the source folder), and I make sure it's ignored in the .gitignore file.
I am using windows 7. I have multiple python virtual environments. Say I added venv_1 to system PATH. In the command line, say I activate another venv_2, now the prompt line shows
(venv_2) C:\>
But if I type python here, it still runs the python in venv_1.
Is this the intended behavior?
This is not the intended behaviour, but it probably means you either made a mistake in setting up the virtual environment, or in activating it.
To be sure what version is being run, try running:
where python
Whatever the top item in the resulting list is, will be the copy of Python Windows would start. If you're right and it does actually point to venv_1, then there must be something wrong with the setup in venv_2.
By running set, you should be able to see a list of all environment variables. Check for:
PATH=<long list of directory names, it should have the venv_2\Scripts at the start>
And:
_OLD_VIRTUAL_PATH=<the same list, without that entry>
It's this simple change to the path that causes Windows to find the Python in your virtual environment first, before the one in your other virtual environment, that you added to the global path.
Note that adding the Scripts folder of the one virtual environment probably isn't a good idea, since you'd only want to use that when the corresponding virtual environment is activated and all the environment variables set accordingly.