从python编译乳胶

Question

I have made some python function for compiling passed string as pdf file using latex. The function works as expected and has been quite useful, therefore I look for ways to improve it.

The code which I have:

def generate_pdf(pdfname,table):
    """
    Generates the pdf from string
    """
    import subprocess
    import os

    f = open('cover.tex','w')
    tex = standalone_latex(table)   
    f.write(tex)
    f.close()

    proc=subprocess.Popen(['pdflatex','cover.tex'])
    subprocess.Popen(['pdflatex',tex])
    proc.communicate()
    os.unlink('cover.tex')
    os.unlink('cover.log')
    os.unlink('cover.aux')
    os.rename('cover.pdf',pdfname)

The problem with the code is that it creates bunch of files named cover in the working directory which afterwards are removed.

How to avoid of creating unneeded files at the working directory?

Solution

def generate_pdf(pdfname,tex):
"""
Genertates the pdf from string
"""
import subprocess
import os
import tempfile
import shutil

current = os.getcwd()
temp = tempfile.mkdtemp()
os.chdir(temp)

f = open('cover.tex','w')
f.write(tex)
f.close()

proc=subprocess.Popen(['pdflatex','cover.tex'])
subprocess.Popen(['pdflatex',tex])
proc.communicate()

os.rename('cover.pdf',pdfname)
shutil.copy(pdfname,current)
shutil.rmtree(temp)

Answer 1

Use a temporary directory. Temporary directories are always writable and can be cleared by the operating system after a restart. tempfile library lets you create temporary files and directories in a secure way.

path_to_temporary_directory = tempfile.mkdtemp()
# work on the temporary directory
# ...
# move the necessary files to the destination
shutil.move(source, destination)
# delete the temporary directory (recommended)
shutil.rmtree(path_to_temporary_directory)