让Python脚本在单独的目录中查找文件

Question

I'm pretty new to python programming, and I wrote a script to automate uploading a file via SFTP to a remote machine. The script works wonderfully, but there is an issue that I can't seem to figure out. If I'm in the directory in which the file I'm trying to upload is residing, everything goes fine. But, when I type the filename that is not residing in said directory, it doesn't like that. It's a hassle having to browse to different folders each time. I know I can consolidate the files into one folder... But I would love to try and automate this.

The /Downloads directory is hard-coded since that's where most tools reside, does anyone know how I can tweak this line of code to grab the matching file name regardless of the directory the file resides in?

This is what I've written:

#! /usr/bin/python2

# includes

import thirdpartylib
import sys

if len(sys.argv) != 6:
    print "Usage: %s file url port username password" % sys.argv[0]
    exit(0)
file = sys.argv[1]
host = sys.argv[2]
port = int(sys.argv[3])
username = sys.argv[4]
password = sys.argv[5]
filelocation = "Downloads/%s" % file

transport = thirdpartylib.Transport((host, port))
transport.connect(username=username, password=password)

sftp = thirdpartylib.SFTPClient.from_transport(transport)

sftp.put(file, filelocation)

sftp.close()
transport.close()

Answer 1

First of all, if you're doing any work with filepaths it is recommended that you use some built-in functionality to construct them to ensure that you have proper file separators etc. os.path.join is great for this.

That being said, I would recommend having the user pass in the file path as either an absolute path (in which case it can live anywhere on the machine) or a relative path (in which case it is relative to the current directory). I would not append Downloads/ to all the file paths as that obviously breaks any absolute paths and it requires the individual calling your program to know the internals of it. I think of this as the file path equivalent of a magic number .

So what that boils down to changing the filelocation to simply be the file input argument itself.

filelocation = sys.argv[1]

# You can even do some validation if you want
is not os.path.isfile(filelocation):
    print "File '%s' does not exist!" % filelocation

If you really want that Downloads/ folder to be the default (if the file path isn't an absolute path), you can check to see if the input is an absolute path (using os.path.isabs ) and if it's not, then specify that it's in the Downloads/ directory.

if not os.path.isabs(filelocation):
    filelocation = os.path.join('Downloads', filelocation)

Then users could call your script in two ways:

# Loads file in /absolute/path/to/file
./script.py /absolute/path/to/file ...

# Loads filename.txt from Downloads/filename.txt
./script.py filename.txt ...

Also, it looks like you may have your sftp.put input arguments reversed. The local filename should come first.

Answer 2

I think you want filelocation as the first argument to stfp.put , as that is supposed to be the filename on the local machine. Also, you probably want to put a slash in front of Downloads .