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Mounting a directory within a docker build

I'm wondering how to use a simple script with a docker container.
The script is:
example python script
# Example python script
import argparse
import pathlib
def run(
*,
input: pathlib.Path | str,
output: pathlib.Path | str,
) -> None:
pathlib.Path(output).write_text(pathlib.Path(input).read_text().upper())
def main() -> int:
desc = "example script"
parser = argparse.ArgumentParser(
description=desc,
formatter_class=argparse.RawDescriptionHelpFormatter,
)
parser.add_argument(
"-i",
"--input",
help=("input file"),
required=True,
)
parser.add_argument(
"-o",
"--output",
help=("output file"),
)
parser.add_argument(
"-x",
"--overwrite",
help=("Whether to overwrite previously created file."),
action="store_true",
)
args = parser.parse_args()
if not pathlib.Path(args.input).exists():
raise FileNotFoundError(f"input file {args.input} not found")
if not args.output:
raise argparse.ArgumentError(f"output not given")
if pathlib.Path(args.output).exists() and not args.overwrite:
raise FileExistsError(f"{args.output} already exists. ")
run(input=args.input, output=args.output)
if __name__ == "__main__":
raise SystemExit(main())
The script works fine on my system (without docker).
example docker file
The Dockerfile is:
FROM python:3.10.6-bullseye
COPY . .
ENTRYPOINT ["python", "example.py"]
This works (ish) after the following:
# build
docker build -t demo .
# run
docker run demo --help
Which outputs:
usage: example.py [-h] -i INPUT [-o OUTPUT] [-x]
example.
options:
-h, --help show this help message and exit
-i INPUT, --input INPUT
input file
-o OUTPUT, --output OUTPUT
output file
-x, --overwrite Whether to overwrite previously created file.
But I'm not sure how to use it with the -i and -o arguments.
what I'd like to do
I'd like to be able to do the following:
echo "text" > input.txt
# Create output from input
docker run demo -i input.txt -o output.txt
# Create output from input and say it's ok to overwrite
docker run demo -i input.txt -o output.txt -x
And after this there by a output.txt file created which has TEXT in it.
Error
I've tried to do this with the above command, and it doesn't work.
Eg:
echo "this" > input.txt
docker run demo -i input.txt -o output.txt -x
After this there is no output.txt file created which has THIS in it.
Attempted solution (--mount within the shell command)
Using the following seems to work - but it feels as though It's a lot in a shell command :
docker run \
--mount type=bind,source="$(pwd)",target=/check \
--workdir=/check demo:latest \
-i input.txt -o output.txt -x
Is there a way to do the --mount within the dockerfile itself?

I am doing a similar thing by running a compiler inside the docker container.
Obviously the docker image gets built whenever there is a new version of the compiler or the underlying image.
The container gets to run whenever I want to compile something. And here I have to mount source and target directories, but my docker command looks smaller than yours:
docker run --rm -v /sourcecode:/project:ro -v /compiled:/output:rw -v cache:/cache:rw compilerimagename
All the rest is defined within the image.

How to run the code in an __init__.py

I have found some code that I think will allow me to communicate with my Helios Heat recovery unit. I am relatively new to Python (but not coding in general) and I really cannot work out how to use this code. It is obviously written for smarthome.py but I'd like to use it from the command line.
I can also see that the way this file is constructed is probably not the best way to construct an __init__.py but I'd like to try and use it first.
So, how do I run this code? https://github.com/mtiews/smarthomepy-helios
Cheers

After git clone https://github.com/mtiews/smarthomepy-helios.git: either
invoke python with the __init__.py script as argument:
python smarthomepy-helios/__init__.py
or
make the __init__.py executable and run it:
chmod u+x smarthomepy-helios/__init__.py
smarthomepy-helios/__init__.py
Running it either way gives me
2016-02-20 18:07:51,791 - root - ERROR - Helios: Could not open /dev/ttyUSB0.
Exception: Not connected
But passing --help I get some nice synopsis:
$> python smarthomepy-helios/__init__.py --help
usage: __init__.py [-h] [-t PORT] [-r READ_VAR] [-w WRITE_VAR] [-v VALUE] [-d]
Helios ventilation system commandline interface.
optional arguments:
-h, --help show this help message and exit
-t PORT, --tty PORT Serial device to use
-r READ_VAR, --read READ_VAR
Read variables from ventilation system
-w WRITE_VAR, --write WRITE_VAR
Write variable to ventilation system
-v VALUE, --value VALUE
Value to write (required with option -v)
-d, --debug Prints debug statements.
Without arguments all readable values using default tty will be retrieved.

how to load python script in interactive shell

I am trying sudo python get_gps.py -c and expecting it to load the script and then present the interactive shell to debug the script live as opposed to typing it in manually.

From the docs:
$ python --help
usage: /usr/bin/python2.7 [option] ... [-c cmd | -m mod | file | -] [arg] ...
Options and arguments (and corresponding environment variables):
-B : don't write .py[co] files on import; also PYTHONDONTWRITEBYTECODE=x
-c cmd : program passed in as string (terminates option list)
-d : debug output from parser; also PYTHONDEBUG=x
-E : ignore PYTHON* environment variables (such as PYTHONPATH)
-h : print this help message and exit (also --help)
-i : inspect interactively after running script; forces a prompt even
if stdin does not appear to be a terminal; also PYTHONINSPECT=x
use -i option

Python argparse: Mutually exclusive required group with a required option

I am trying to have a required mutually exclusive group with one required parameter. Below is the code which I have put
#!/usr/bin/python
import argparse
import sys
# Check for the option provided as part of arguments
def parseArgv():
parser = argparse.ArgumentParser()
group = parser.add_mutually_exclusive_group()
group.add_argument("-v", "--verbose", choices=[1,2,3,4],
help = "Increase verbosity")
group.add_argument("-q", "--quiet", action="store_true", help = "Run quietly")
name = parser.add_mutually_exclusive_group(required=True)
name.add_argument("-n", "--name", help = "Name of the virtual machine")
name.add_argument("-t", "--template", help = "Name of the template to use \
for creating vm. If path is not provided then it will be looked \
under template directory.")
parser.add_argument("-s", "--save", help = "Save the machine template. If \
path is not provided then it will be saved under template directory.");
#parser.add_argument("-k", "--kick_start", required = True, help = "Name of the \
# kick start file. If path is not provided then it will be look into http \
# directory.")
if len(sys.argv) == 1:
parser.print_help()
args = parser.parse_args()
if __name__ == '__main__':
parseArgv()
Now the output of this program as follow
$ python test.py
usage: test.py [-h] [-v {1,2,3,4} | -q] (-n NAME | -t TEMPLATE) [-s SAVE]
optional arguments:
-h, --help show this help message and exit
-v {1,2,3,4}, --verbose {1,2,3,4}
Increase verbosity
-q, --quiet Run quietly
-n NAME, --name NAME Name of the virtual machine
-t TEMPLATE, --template TEMPLATE
Name of the template to use for creating vm. If path
is not provided then it will be looked under template
directory.
-s SAVE, --save SAVE Save the machine template. If path is not provided
then it will be saved under template directory.
usage: test.py [-h] [-v {1,2,3,4} | -q] (-n NAME | -t TEMPLATE) [-s SAVE]
test.py: error: one of the arguments -n/--name -t/--template is required
But if I un-comment the from line 20 - 22 then the output change as below
$ python test.py
usage: test.py [-h] [-v {1,2,3,4} | -q] (-n NAME | -t TEMPLATE) [-s SAVE] -k
KICK_START
optional arguments:
-h, --help show this help message and exit
-v {1,2,3,4}, --verbose {1,2,3,4}
Increase verbosity
-q, --quiet Run quietly
-n NAME, --name NAME Name of the virtual machine
-t TEMPLATE, --template TEMPLATE
Name of the template to use for creating vm. If path
is not provided then it will be looked under template
directory.
-s SAVE, --save SAVE Save the machine template. If path is not provided
then it will be saved under template directory.
-k KICK_START, --kick_start KICK_START
Name of the kick start file. If path is not provided
then it will be look into http directory.
usage: test.py [-h] [-v {1,2,3,4} | -q] (-n NAME | -t TEMPLATE) [-s SAVE] -k
KICK_START
test.py: error: argument -k/--kick_start is required
But I want that either -n / -t along with -k become mandatory. How to achieve the same.

You have already achieved it! Argparse only prints the first error it finds, so while it may look like it's only checking -k, it actually recuires -n/-t too. You can see this by actually giving it the -k argument.
If you provide the -k argument, the error message will change from test.py: error: argument -k/--kick_start is required to test.py: error: one of the arguments -n/--name -t/--template is required.

Requiring flags based upon other flags argparse

I have a series of flags...
--one
--two
-a
-b
-c
-d
I would like to have -a and -b required whenever I start with --one and -c, -d whenever I start with --two.
How exactly do I accomplish this? I know I can make an option required, but that's not the same as requiring options based on already given options.