Shell script as file with output to python

Question

I have a simple shell script with input and output to console. I want to get console output and errs to variables in Python, preferably with subprocess.run(). This example is simplified but problem is the same - i'm running protoc compilations over hundreds of protofiles.

# test.sh

echo $1 $2

Script is called in Python, it's working (shell script do the job and it's outputed to console) but i can't get the console output back to Python - nothing is printed. What i've tried:

proc = subprocess.run(["test.sh", "test", "test2"],
                      encoding="utf-8",
                      shell=True,
                      text=True,
                      capture_output=True)

print(proc.stdout)

session = subprocess.Popen(['test.sh', "test", "test2"],stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)

stdout, stderr = session.communicate()

print(stdout)

with subprocess.Popen(["test.sh", "test", "test2"],
                     stdout=subprocess.PIPE,
                     stderr=subprocess.PIPE,
                     shell=True) as p:
     for line in p.stdout:
         print(line)

Thank you.

Answer 1

Try to specify sh/bash explicitly in the list of subprocess.run(*popenargs, ...) and remove shell=True parameter:

proc = subprocess.run(
    ["sh", "./test.sh", "test", "test2"],
    encoding="utf-8",
    text=True,
    capture_output=True
)

print(proc.stdout)
print(proc.stderr)

Also, make sure you print(proc.stderr) to check if there're any errors in stderr.