Venv in Parent IPykernel - an IPython kernel for Jupyter that runs out the closest venv
Check the medium or dev.to articles to read more about the background behind this project.
Do you use venv
's for all of your environments? Do you run Jupyter out of a
system/user installed location or via JupyterHub? Are you bored of making a
kernel for every single venv? Then this is the package for you!
vip-ipykernel overwrites the default python3
kernel and replaces it with one
which will traverse directories upwards until it finds a .venv
directory, if
it finds one then it will start the kernel with python out of that directory, if
it does not find a venv then it will carry on with the default python3.
NOTE: Your venv must have ipykernel installed in it, as this 'kernel' just searches for and launches ipykernel out of the local venv. If ipykernel is not available inside the venv then it will fail to start.
This only needs to be installed once, you can do this with pip install vip-ipykernel --user
to install it into your local user environment.
Once the package is installed, run python3 -m vip_ipykernel.kernelspec --user
to install the kernel, now when you run a notebook with the default python3
kernel it will instead use the venv in a parent directory.
If you want to revert the changes, run python3 -m ipykernel install --user
,
this will re-install the default python3
kernel.
Alternatively, if you don't want to overwrite the default kernel, then you can
pass a name (python3 -m vip_ipykernel.kernelspec --user --name venv-kernel
) to
so that the kernel appears separately in the list of kernels and the default
behaviour is not modified.
The standard python3 kernel is:
{
"argv": [
"/usr/bin/python3",
"-m",
"ipykernel_launcher",
"-f",
"{connection_file}"
],
"display_name": "Python 3",
"language": "python"
}
This just says "Run using python3
to run ipykernel_launcher
with an argument
-f {connection_file}
". When you install the vip ipykernel this is replace by:
{
"argv": [
"/usr/bin/python3",
"-m",
"vip_ipykernel_launcher",
"-m",
"ipykernel_launcher",
"-f",
"{connection_file}"
],
"display_name": "Python 3",
"language": "python"
}
Which will instead run the vip_ipykernel.vip_ipykernel_launcher
module,
passing it the arguments -m ipykernel_launcher -f {connection_file}
. The
module runs a function venv_search
which looks in the current directory, and
upwards to any parent directories, until it finds a .venv
or venv
directory
containing bin/python3
.
If it finds a venv with python3 in it, it passes the arguments -m ipykernel_launcher -f {connection_file}
to that python executable, which starts
and connects the kernel from that venv to your current session, in the same way
that a kernel installed for that specific venv would.
If it does not find a venv, then it will default to the system python executable
and behave like the standard python3
kernel.
VSCode manages kernels for its notebooks with its own system, so it will not use the vip-ipykernel.
Currently only venv's named .venv
or venv
are searched for, if your venv has
a different name it won't be found, and if you have multiple venv's available
then the first one (sorted alphanumerically, so .venv
takes priority over
venv
) will be used.
The kernel implementation and tests are largely copy-and-paste'd directly from the ipykernel project with some minor modifications made to search for a venv and launch python out of it if possible.
Thank you to Thomas Kluyver (@takluyver) for the review of the initial code in the first PR: #1
- Expand tests to different versions of ipykernel/jupyter_core
- Look at ways to show kernel errors
- Support for other environments:
- Poetry-created venvs (
poetry env info --path
) - Pipenv-created venvs
- Pyenv-created venvs
- Conda-created environments
- User-configured venvs
- Reading from vscode configuration?
- etc...
- Poetry-created venvs (