Structuring main method

I have a python script that will do 3 things, check to see if a file exists in a directory, copy specific files from one directory to another, and execute another python script. Right now if I run the script it runs through all 3 functions, regardless of if the file exists in the test directory.

What I want it to do is check to see if the file exists. If it does, copy it, and once it's copied execute the other script. I am having trouble figuring out a simple way to link them all together. Here is my script.

import os
import os.path
from os import path
import shutil


def check_file():
file_exists = False
for deploy_file in os.listdir("C:test1test.txt"):
if deploy_file.startswith("test"):
file_exists = True
else:
exit(1)
print file_exists


def copy_file():
src = "C:test1"
dst = "C:test2"

files = [i for i in os.listdir(src) if i.startswith("test") and path.isfile(path.join(src, i))]
print files
for f in files:
shutil.copy(path.join(src, f), dst)


def run_script():
os.system("pathofscript") # for testing its just a script that prints "hello world"


def main():
check_file()
copy_file()
run_script()


main()


So by running this as-is the output will be:

True
['test.txt']
"hello world"


How can I write my main() method to do what I am trying to do?

You need to use return statements to make these functions produce a programmatically useful result (print is not programmatically useful). Then you can use that result in the main method, e.g. controlling the other methods with if check_file():
– ShadowRanger
3 mins ago

return

print

if check_file():

Also, having check_file call exit(1) as the else case in the loop means your program would exit if any entry fails the test.
– ShadowRanger
2 mins ago

check_file

exit(1)

else

1 Answer
1

You can verify if the file exists with an if statement then run the other two functions. You will have to update check_file() to return True or False

check_file()

def check_file():
file_exists = False
for deploy_file in os.listdir("C:test1test.txt"):
if deploy_file.startswith("test"):
file_exists = True
else:
file_exists = False
return file_exists


Then you can use this as your main function

def main():
if check_file():
copy_file()
run_script()
else:
exit(1)


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