edit one line across multiple files using file methods - python

Question

this is my code:

the "constants"

import os
import tempfile
import shutil

file_domini = open("ns_list.txt", "r")    #contains a list of ns
dir_name = '/var/named/'
filename_suffix = '.zone'
bad_words = ['TTL']
prep_str = "$TTL 1d"

3 functions:

def line_prepender(filename, string):       #add a string on file top
    with open(filename, 'r+') as f:
        content = f.read()
        f.seek(0, 0)
        f.write(string.rstrip('\r\n') + '\n' + content)


def create_temporary_copy(path):            #create a copy of path using temp files
    temp_dir = tempfile.gettempdir()
    temp_path = os.path.join(temp_dir, 'zone_file.tmp')
    shutil.copy2(path,  temp_path)
    return temp_path


def zone_file_checker(percorso_file):       #add/edit/check some condition of zone file
    file_di_zona = open(filename, 'r')      #"file di zona" means zone file
    text = file_di_zona.read()

    # copy file_di_zona on tmp and remove lines containing $TTL
    # occorrenze di TTL
    with open(create_temporary_copy(filename), 'r+') as tmp:

        for line in text:
            # search and remove eventually wrong TTL strings
            if not any(bad_word in line for bad_word in bad_words):
                tmp.write(line)

            # add $TTL 1d in prepending
            line_prepender(tmp, prep_str)
            #continue

the main problem

            #continue
            #this 4 lines
            # add @ before mx records
            if line.lstrip().startswith('IN') and 'MX' in line: 
                line = "@" + line[1:]
                tmp.write(line)

        print tmp
        tmp.close()
    file_di_zona.close()

main function:

for riga in file_domini:                   #"riga" means "line"
    # modifico casi particolari
    if not riga.startswith('('):
        # replace to fit file name syntax
        zone_name = riga.replace('.', '_').replace('\n', '')

        filename = dir_name + zone_name + filename_suffix
        print filename

        count = 0
        try:
            zone_file_checker(filename)

        except IOError as e:
            count += 1
            # print filename + ":"
            print "    I/O error({0}): {1}".format(e.errno, e.strerror)

if count > 0:
            print "IOError: %d domain names not found" % count

file_domini.close()

as you can see in the comment in the third subfunction, at the

# add @ before mx records
if line.lstrip().startswith('IN') and 'MX' in line:     #the main problem
    line = "@" + line[1:]
    tmp.write(line)

it doesn't write on file.

this is a sample of zone file:

              IN      MX    20 mail2.example.com. 
              IN  MX    50 mail3              
example.com.  IN      A     192.0.2.1             
              IN      AAAA  2001:db8:10::1       
ns            IN  A     192.0.2.2             
              IN      AAAA  2001:db8:10::2     

and this is a sample of ns_list.txt

example1.com
( dns.example.it. )
( dns1.example.it. )
example2.eu
( dns1.example.it. )
( dns.example.it. )
example3.mobi
( dns2.example.it. )
( dns.example.it. )
example4.com
( dns1.novanet.it. )
( dns.novanet.it. )

there are some files named sitename_com.zone, sitename_it.zone, sitename_ext.zone, corrisponding to each domain (example1.com, example2.eu, ecc)

the main thing I need to fix is that i can not either write on a copy(temp) of these files or directly on them.

Answer 1

I edited some line of code now works fine

def zone_file_checker(filename):

zone_file = open(filename, 'r')

# copio file_di_zona su tmp, e rimuovo righe di eventuali
# occorrenze di TTL
with open(create_temporary_copy(filename), 'r+') as tmp:
    line_prepender(tmp, prep_str)
    # print("byte #" + str(tmp.tell()))
    for line in zone_file:  # if you put tmp it doesn't print @ before mx

        # vedi context manager e any
        if not '$TTL' in line:
            # aggiungo @ davanti agli mx records
            if line.lstrip().startswith('IN') and 'MX' in line:
                line = "@" + line[1:]
                tmp.write(line)
            else:
                tmp.write(line)

    tmp.seek(0, 0)
    # print(tmp.tell())
    print(tmp.read())

    tmp.close()
zone_file.close()

and the prepender function

def line_prepender(filename, stringa):

filename.seek(0, 0)
filename.writelines([stringa.rstrip('\r\n') + '\n'])

Answer 2

def zone_file_checker(filename):
    """ aggiunge, modifica e verifica
   le condizioni per cui il file di zona
    sia corretto e non dia problemi
    in fase di migrazione"""
    text = open(filename, 'r')


    # copio file_di_zona su tmp, e rimuovo righe di eventuali
    # occorrenze di TTL
    with open(create_temporary_copy(filename), 'r+') as tmp:

        for line in text:

            # vedi context manager e any


if not any(bad_word in line for bad_word in bad_words):
                if line.lstrip().startswith('IN') and 'MX' in line:
                    line = "@" + line[1:]
                    tmp.write(line)
                else:
                    tmp.write(line)

            # aggiungo $TTL 1d in prepending
            # line_prepender(tmp, prep_str)

            # aggiungo @ davanti agli mx records




        # esco
        print tmp
        tmp.close()
    text.close()

u made 2 mistakes

1)

file_di_zona = open(filename, 'r')      #"file di zona" means zone file
    text = file_di_zona.read()

solution use below line dont read. :

text = open(filename, 'r')

2)two ifs for bad words and line

if not any(bad_word in line for bad_word in bad_words):


     if line.lstrip().startswith('IN') and 'MX' in line:
                        line = "@" + line[1:]
                        tmp.write(line)
                    else:
                        tmp.write(line)

last i dont know why r u using line prepender . dont use it.

Answer 3

In a call to

        line_prepender(tmp, prep_str)

tmp is not a filename, as line_prepender expects. This is one possible place where things start to fall apart.