I'm trying to take the output of one script and pass it using sys.argv to my python script.
The question I have is whether there's a way to accomplish this similar to
python runfile.py $(node parse.js)
For testing, runfile.py just consists of:
import sys
print sys.argv
But, as you might've guessed, that just logs ['runfile.py'].
Am I totally barking up the wrong tree here? If so, can someone explain or link to an explanation of how to pass the output of, say, a javascript file to a python script?
Edit: is there a way to mark the $(node parse.js) part as a separate argument that should be evaluated?
Instead of passing the output of node parse.js to your python script via command line arguments (sys.argv) you could use stdin and unix pipes:
node parse.js | python runfile.py
And edit runfile.py to look like:
import sys
print sys.stdin
Related
For the life of me i can't figure this one out.
I have 2 applications build in python, so 2 projects in different folders, is there a command to say in the first application like run file2 from documents/project2/test2.py ?
i tried something like os.system('') and exec() but that only seems to work if its in the same folder. How can i give a command a path like documents/project2 and then for example:
exec(documents/project2 python test2.py) ?
short version:
Is there a command that runs python test2.py while that test2 is in a completely different file/project?
thnx for all feedback!
There's a number of approaches to take.
1 - Import the .py
If the path to the other Python script can be made relative to your project, you can simply import the .py. This will cause all the code at the 'root' level of the script to be executed and makes functions as well as type and variable definitions available to the script importing it.
Of course, this only works if you control how and where everything is installed. It's the most preferable solution, but only works in limited situations.
import ..other_package.myscript
2 - Evaluate the code
You can load the contents of the Python file like any other text file and execute the contents. This is considered more of a security risk, but given the interpreted nature of Python in normal use not that much worse than an import under normal circumstances.
Here's how:
with open('/path/to/myscript.py', 'r') as f:
exec(f.read())
Note that, if you need to pass values to code inside the script, or out of it, you probably want to use files in this case.
I'd consider this the least preferable solution, due to it being a bit inflexible and not very secure, but it's definitely very easy to set up.
3 - Call it like any other external program
From a Python script, you can call any other executable, that includes Python itself with another script.
Here's how:
from subprocess import run
run('python path/to/myscript.py')
This is generally the preferable way to go about it. You can use the command line to interface with the script, and capture the output.
You can also pipe in text with stdin= or capture the output from the script with stdout=, using subprocess.Popen directly.
For example, take this script, called quote.py
import sys
text = sys.stdin.read()
print(f'In the words of the poet:\n"{text}"')
This takes any text from standard in and prints them with some extra text, to standard out like any Python script. You could call it like this:
dir | python quote.py
To use it from another Python script:
from subprocess import Popen, PIPE
s_in = b'something to say\nright here\non three lines'
p = Popen(['python', 'quote.py'], stdin=PIPE, stdout=PIPE)
s_out, _ = p.communicate(s_in)
print('Here is what the script produced:\n\n', s_out.decode())
Try this:
exec(open("FilePath").read())
It should work if you got the file path correct.
Mac example:
exec(open("/Users/saudalfaris/Desktop/Test.py").read())
Windows example:
exec(open("C:\Projects\Python\Test.py").read())
I am trying to use Python to run an executable (Windows 7) with parameters. I have been able to make the program run, but the amount of parameters I can use that will prove the Python script worked with parameters is limited. The best one is formatted like so:
-debugoutput debug.txt
I have tested this using a windows shortcut with an edited target and it works, it creates a debug output in the program directory.
Here is the code I am using:
import subprocess
args = [r"C:\Users\MyName\LevelEditor\LevelEditor.exe", "-debugoutput debug.txt"]
subprocess.call(args)
This does run the program, but the debug output is not created. I have tried putting an "r" in front of the parameter but this made no difference. I assume it is a simple formatting error but I can't find any examples to learn from that are doing the same thing.
UPDATE:
Thanks for the answers everyone, all the same, simple formatting error indeed.
In-code definition results in invocation of shell command line:
C:\Users\MyName\LevelEditor\LevelEditor.exe "-debugoutput debug.txt"
As you can see, by merging -debugoutput debug.txt to single list element, you explicitly stated that space between them shouldn't be parsed as command line argument separator.
To achieve expected behavior put file name string as separate element to argument list.
[r"C:\Users\MyName\LevelEditor\LevelEditor.exe", "-debugoutput", "debug.txt"]
As far as I know you need to split the arguments by the space, so your args would look like:
args = [r"C:\Users\MyName\LevelEditor\LevelEditor.exe", "-debugoutput", "debug.txt"]
Does that work?
I do not know if it works, but
import subprocess
args = [r"C:\Users\MyName\LevelEditor\LevelEditor.exe", "-debugoutput", "debug.txt"]
subprocess.run(args)
Following the docs
I just want to have some ideas to know how to do that...
I have a python script that parses log files, the log name I give it as an argument so that when i want to run the script it's like that.. ( python myscript.py LOGNAME )
what I'd like to do is to have two scripts one that contains the functions and another that has only the main function so i don't know how to be able to give the argument when i run it from the second script.
here's my second script's code:
import sys
import os
path = "/myscript.py"
sys.path.append(os.path.abspath(path))
import myscript
mainFunction()
the error i have is:
script, name = argv
valueError: need more than 1 value to unpack
Python (just as most languages) will share parameters across imports and includes.
Meaning that if you do:
python mysecondscript.py heeey that will flow down into myscript.py as well.
So, check your arguments that you pass.
Script one
myscript = __import__('myscript')
myscript.mainfunction()
script two
import sys
def mainfunction():
print sys.argv
And do:
python script_one.py parameter
You should get:
["script_one.py", "parameter"]
You have several ways of doing it.
>>> execfile('filename.py')
Check the following link:
How to execute a file within the python interpreter?
Is anyone able to tell me how to write a conditional for an argument on a python script? I want it to print "Argument2 Entered" if it is run with a second command line arguments such as:
python script.py argument1 argument2
And print "No second argument" if it is run without command line arguments, like this:
python script.py argument1
Is this possible?
import sys
if len(sys.argv)==2: # first entry in sys.argv is script itself...
print "No second argument"
elif len(sys.argv)==3:
print "Second argument"
There are many answers to this, depending on what exactly you want to do and how much flexibility you are likely to need.
The simplest solution is to examine the variable sys.argv, which is a list containing all of the command-line arguments. (It also contains the name of the script as the first element.) To do this, simply look at len(sys.argv) and change behaviour based on its value.
However, this is often not flexible enough for what people expect command-line programs to do. For example, if you want a flag (-i, --no-defaults, ...) then it's not obvious how to write one with just sys.argv. Likewise for arguments (--dest-dir="downloads"). There are therefore many modules people have written to simplify this sort of argument parsing.
The built-in solution is argparse, which is powerful and pretty easy-to-use but not particularly concise.
A clever solution is plac, which inspects the signature of the main function to try to deduce what the command-line arguments should be.
There are many ways to do this simple thing in Python. If you are interested to know more than I recommend to read this article. BTW I am giving you one solution below:
import click
'''
Prerequisite: # python -m pip install click
run: python main.py ttt yyy
'''
#click.command(context_settings=dict(ignore_unknown_options=True))
#click.argument("argument1")
#click.argument("argument2")
def main(argument1, argument2):
print(f"argument1={argument1} and argument2={argument2}")
if __name__ == '__main__':
main()
Following block should be self explanatory
$ ./first.py second third 4th 5th
5
$ cat first.py
#!/usr/bin/env python
import sys
print (len(sys.argv))
This is related to many other posts depending upon where you are going with this, so I'll put four here:
What's the best way to grab/parse command line arguments passed to a Python script?
Implementing a "[command] [action] [parameter]" style command-line interfaces?
How can I process command line arguments in Python?
How do I format positional argument help using Python's optparse?
But the direct answer to your question from the Python docs:
sys.argv -
The list of command line arguments passed to a Python script. argv[0] is the script name (it is operating system dependent whether this is a full pathname or not). If the command was executed using the -c command line option to the interpreter, argv[0] is set to the string '-c'. If no script name was passed to the Python interpreter, argv[0] is the empty string.
To loop over the standard input, or the list of files given on the command line, see the fileinput module.
I'm trying to create a program that can be called from the command line and use keyword arguments in python 2.6. So far I've tried:
#!/usr/bin/python
def read(foo = 5):
print foo
return 0
if __name__ == '__main__'
read()
When I try to run this from the command line: ./test.py the program prints 5 as expected. Is there a way to use ./test.py foo=6? I want to preserve the keyword arguments.
It seems like a simple question, but I haven't found a good source for this.
python has built in library to help you achieve passing command line arguments to a script
argparse. THe usage is a little different then what you are describing in your question though...
On a basic level you can access all command line arguments by sys.argv, which will be a list of arguments
Sorry should have mentioned the python 2.6 library is called optparse
Something like this?
if __name__ == '__main__':
kwargs = dict(x.split('=', 1) for x in sys.argv[1:])
read(**kwargs)
That said, argparse and optparse are probably going to give you something more robust and more natural for someone used to the commandline. (Not to mention, supporting arguments of types other than string.)
Oh, and if what you're really after is just interactive use of your function, use the interactive interpreter; either python or ipython. You'd need to put the code into a file ending in .py and import it, then you could just call it.
A less usual, but very interesting alternative is docopt: a library that generates an argument parser from the help message that you write for your program (on github).