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Using the ssh agent inside a python script

I'm pulling and pushing to a github repository with a python script. For the github repository, I need to use a ssh key.
If I do this manually before running the script:
eval $(ssh-agent -s)
ssh-add ~/.ssh/myprivkey
everything works fine, the script works. But, after a while, apparently the key expires, and I have to run those 2 cmds again
The thing is, if I do that inside the python script, with os.system(cmd), it doesn't work, it only works if I do that manually
I know this must be a messy way to use the ssh agent, but I honestly don't know how it works, and I just want the script to work, that's all
The script runs once an hour, just in case

While the normal approach would be to run your Python script in a shell where the ssh agent is already running, you can also consider an alternative approach with sshify.py
# This utility will execute the given command (by default, your shell)
# in a subshell, with an ssh-agent process running and your
# private key added to it. When the subshell exits, the ssh-agent
# process is killed.

Consider defining the ssh key path against a host of github.com in your ssh config file as outlined here: https://stackoverflow.com/a/65791491/14648336
If Linux then at this path ~/.ssh/ create a file called config and input something similar to in the above answer:
Host github.com
HostName github.com
User your_user_name
IdentityFile ~/.ssh/your_ssh_priv_key_file_name
This would save the need for starting an agent each time and also prevent the need for custom environment variables if using GitPython (you mention using Python) as referenced in some other SO answers.

Invoking multiple docker commands via python

I am trying to invoke a docker instance from python subprocess (windows / wsl).
Let's just assume that the docker I need to run is a simple docker run -it busybox (it's not going to be that, but it's a shell for experimenting) but once loaded I need to insert programmatically (asynchronous or blocked, either way is fine) some commands for git to pull some sources and then compile them and deploy them (before invoking docker, I am asking the user to choose a tag from a set of repos).
So far using the normal subprocess.Popen I was able to tap in to docker, but I need to have this persistent until I leave docker interactive shell (from busybox).
Is this possible to be done, or once I get the subprocess done it stops at the next command (as it happens now)?
(PS I can post some of my code, but I need to clean up some bits first)

Can you possibly do a simple while loop? My other thoughts would be if all the commands are the same each time they are called, put them in a batch file and call the batch from python. All I can come up with without code.

How do you debug python code with kubernetes and skaffold?

I am currently running a django app under python3 through kubernetes by going through skaffold dev. I have hot reload working with the Python source code. Is it currently possible to do interactive debugging with python on kubernetes?
For example,
def index(request):
import pdb; pdb.set_trace()
return render(request, 'index.html', {})
Usually, outside a container, hitting the endpoint will drop me in the (pdb) shell.
In the current setup, I have set stdin and tty to true in the Deployment file. The code does stop at the breakpoint but it doesn't give me access to the (pdb) shell.

There is a kubectl command that allows you to attach to a running container in a pod:
kubectl attach <pod-name> -c <container-name> [-n namespace] -i -t
-i (default:false) Pass stdin to the container
-t (default:false) Stdin is a TTY
It should allow you to interact with the debugger in the container.
Probably you may need to adjust your pod to use a debugger, so the following article might be helpful:
How to use PDB inside a docker container.
There is also telepresence tool that helps you to use different approach of application debugging:
Using telepresence allows you to use custom tools, such as a debugger and IDE, for a local service and provides the service full access to ConfigMap, secrets, and the services running on the remote cluster.
Use the --swap-deployment option to swap an existing deployment with the Telepresence proxy. Swapping allows you to run a service locally and connect to the remote Kubernetes cluster. The services in the remote cluster can now access the locally running instance.

It might be worth looking into Rookout which allows in-prod live debugging of Python on Kubernetes pods without restarts or redeploys. You lose path-forcing etc but you gain loads of flexibility for effectively simulating breakpoint-type stack traces on the fly.

This doesn't use Skaffold, but you can attach the VSCode debugger to any running Python pod with an open source project I wrote.
There is some setup involved to install it on your cluster, but after installation you can debug any pod with one command:
robusta playbooks trigger python_debugger name=myapp namespace=default

You can take a look at okteto/okteto. There's a good tutorial which explains how you can develop and debug directly on Kubernetes.

run ssh command remotely without redirecting output

I want to run a python script on my server (that python script has GUI). But I want to start it from ssh. Something like this:
ssh me#server -i my_key "nohup python script.py"
... > let the script run forever
BUT it complains "unable to access video driver" since it is trying to use my ssh terminal as output.
Can I somehow make my commands output run on server machine and not to my terminal... Basically something like "wake-on-lan functionality" -> tell the server you want something and he will do everything using its own system (not sending any output back)

What about
ssh me#server -i my_key "nohup python script.py >/dev/null 2>&1"
You can use redirection to some remote logfile instead of /dev/null of course.
? :)
EDIT: GUI applications on X usually use $DISPLAY variable to know where they should be displayed. Moreover, X11 display servers use authorization to permit or disallow applications connecting to its display. Commands
export DISPLAY=:0 && xhost +
may be helpful for you.

Isn't it possible for you to rather use python ssh extension instead of calling external application?
It would:
run as one process
guarantee that invocation will be the same among all possible system
lose the overhead from "execution"
send everything trough ssh (you won't have to worry about input like "; possibly local executed command)
If not, go with what Piotr Wades suggested.

Execute remote python script via SSH

I want to execute a Python script on several (15+) remote machine using SSH. After invoking the script/command I need to disconnect ssh session and keep the processes running in background for as long as they are required to.
I have used Paramiko and PySSH in past so have no problems using them again. Only thing I need to know is how to disconnect a ssh session in python (since normally local script would wait for each remote machine to complete processing before moving on).

This might work, or something similar:
ssh user#remote.host nohup python scriptname.py &
Basically, have a look at the nohup command.

On Linux machines, you can run the script with 'at'.
echo "python scriptname.py" ¦ at now

If you are going to perform repetitive tasks on many hosts, like for example deploying software and running setup scripts, you should consider using something like Fabric
Fabric is a Python (2.5 or higher) library and command-line tool for
streamlining the use of SSH for application deployment or systems
administration tasks.
It provides a basic suite of operations for executing local or remote
shell commands (normally or via sudo) and uploading/downloading files,
as well as auxiliary functionality such as prompting the running user
for input, or aborting execution.
Typical use involves creating a Python module containing one or more
functions, then executing them via the fab command-line tool.

You can even use tmux in this scenario.
As per the tmux documentation:
tmux is a terminal multiplexer. It lets you switch easily between several programs in one terminal, detach them (they keep running in the background) and reattach them to a different terminal. And do a lot more
From a tmux session, you can run a script, quit the terminal, log in again and check back as it keeps the session until the server restart.
How to configure tmux on a cloud server