I'm attempting to write a menu driven modular perl script that will capture user input and automate the network configuration process. This script has to be able to install required Arch packages, configure AP mode, configure either DHCP or a static address for the user selected interface and give an option to enable bridging. (EDIT: The script also needs to be able to enable and configure the dhcpd service)
The part I'm stuck on right now is creating a backup of the rc.conf file, reading the file and editing the lines that need to be modified if a network interface has already been statically configured. This script is for use in ArchLinux, I did some searching around and didn't find anything that met my needs specifically.
Using generic input for
$ip = 1.1.1.1; $Bcast = 2.2.2.2; $netmask = 3.3.3.3; $GW = 4.4.4.4;
I've spent about two hours reading about file I/O and tried several things that didn't work including scrapping the multiple file IO method and using something similar to: while(<IS>){s/^interface.?=(.*)$/"interface=#if[0] \n"/;} with inputs for each of the values that need to be replaced and couldn't get it to actually do anything.
if (system ("cat","/etc/rc.conf","|","grep","interface")){
use File::Copy "cp";
$filename = "/etc/rc.conf";
$tempfile = "/etc/rc.tmp";
$bak = "/etc/rc.bak";
cp($filename,$bak);
open(IS, $filename);
open(OS, ">$tempfile");
while(<IS>){
if($_ =~ /^interface.?=(.*)$/){ print OS"interface=#if[0] \n";}
if($_ =~ /^address.?=(.*)$/){ print OS "address=$ip\n";}
if($_ =~/^netmask.?=(.*)$/){ print OS "netmask=$netmask\n";}
if($_ =~/^broadcast.?=(.*)$/){ print OS "broadcast=$Bcast\n";}
if($_ =~/^gateway.?=(.*)$/){ print OS "gateway=$GW\n"; }
else {print OS $_;}
}
close(IS); close(OS);
unlink($filename); rename($tempfile, $filename);
}
rc.conf before
#
# /etc/rc.conf - Main Configuration for Arch Linux
. /etc/archiso/functions
LOCALE_DEFAULT="en_US.UTF-8"
DAEMON_LOCALE_DEFAULT="no"
CLOCK_DEFAULT="UTC"
TIMEZONE_DEFAULT="Canada/Pacific"
KEYMAP_DEFAULT="us"
CONSOLEFONT_DEFAULT=
CONSOLEMAP_DEFAULT=
USECOLOR_DEFAULT="yes"
LOCALE="$(kernel_cmdline locale ${LOCALE_DEFAULT})"
DAEMON_LOCALE="$(kernel_cmdline daemon_locale ${DAEMON_LOCALE_DEFAULT})"
HARDWARECLOCK="$(kernel_cmdline clock ${CLOCK_DEFAULT})"
TIMEZONE="$(kernel_cmdline timezone ${TIMEZONE_DEFAULT})"
KEYMAP="$(kernel_cmdline keymap ${KEYMAP_DEFAULT})"
CONSOLEFONT="$(kernel_cmdline consolefont ${CONSOLEFONT_DEFAULT})"
CONSOLEMAP="$(kernel_cmdline consolemap ${CONSOLEMAP_DEFAULT})"
USECOLOR="$(kernel_cmdline usecolor ${USECOLOR_DEFAULT})"
MODULES=()
UDEV_TIMEOUT=30
USEDMRAID="no"
USEBTRFS="no"
USELVM="no"
HOSTNAME="archiso"
DAEMONS=(hwclock syslog-ng)
interface=eth0
address=192.168.0.99
netmask=255.255.255.0
broadcast=192.168.0.255
gateway=192.168.0.1
rc.conf after
#
# /etc/rc.conf - Main Configuration for Arch Linux
. /etc/archiso/functions
LOCALE_DEFAULT="en_US.UTF-8"
DAEMON_LOCALE_DEFAULT="no"
CLOCK_DEFAULT="UTC"
TIMEZONE_DEFAULT="Canada/Pacific"
KEYMAP_DEFAULT="us"
CONSOLEFONT_DEFAULT=
CONSOLEMAP_DEFAULT=
USECOLOR_DEFAULT="yes"
LOCALE="$(kernel_cmdline locale ${LOCALE_DEFAULT})"
DAEMON_LOCALE="$(kernel_cmdline daemon_locale ${DAEMON_LOCALE_DEFAULT})"
HARDWARECLOCK="$(kernel_cmdline clock ${CLOCK_DEFAULT})"
TIMEZONE="$(kernel_cmdline timezone ${TIMEZONE_DEFAULT})"
KEYMAP="$(kernel_cmdline keymap ${KEYMAP_DEFAULT})"
CONSOLEFONT="$(kernel_cmdline consolefont ${CONSOLEFONT_DEFAULT})"
CONSOLEMAP="$(kernel_cmdline consolemap ${CONSOLEMAP_DEFAULT})"
USECOLOR="$(kernel_cmdline usecolor ${USECOLOR_DEFAULT})"
MODULES=()
UDEV_TIMEOUT=30
USEDMRAID="no"
USEBTRFS="no"
USELVM="no"
HOSTNAME="archiso"
DAEMONS=(hwclock syslog-ng)
interface=eth0
interface=eth0
address=1.1.1.1
address=192.168.0.99
netmask=3.3.3.3
netmask=255.255.255.0
broadcast=2.2.2.2
broadcast=192.168.0.255
gateway=4.4.4.4
I am not going to comment on the wisdom of the rest of your script, but you have:
if (system ("cat","/etc/rc.conf","|","grep","interface")){
system returns 0 on success.
So, you'll enter the block only if that system call fails.
If fact, I am on a Windows system right now with no /etc/rc.conf (but cat and grep thanks to Cygwin. Running the following script:
#!/usr/bin/env perl
use strict; use warnings;
if (system ("cat","/etc/rc.conf","|","grep","interface")){
print "*** it worked! ***\n";
if ($? == -1) {
print "failed to execute: $!\n";
}
elsif ($? & 127) {
printf "child died with signal %d, %s coredump\n",
($? & 127), ($? & 128) ? 'with' : 'without';
}
else {
printf "child exited with value %d\n", $? >> 8;
}
}
produces the output:
cat: /etc/rc.conf: No such file or directory
cat: |: No such file or directory
cat: grep: No such file or directory
cat: interface: No such file or directory
*** it worked! ***
child exited with value 1
That means system returned a failure code. Now, if you want to use shell piping and redirection, you should pass system a string, not a list, and check like this:
if (system ('cat /etc/rc.conf | grep interface') == 0) {
On the other hand, I would rather not trust shells propagating exit status.
The following should point you in a better direction:
#!/usr/bin/env perl
use strict;use warnings;
my %lookup = (
eth0 => {
address => '1.1.1.1',
broadcast => '2.2.2.2',
netmask => '3.3.3.3',
gateway => '4.4.4.4',
},
wlan0 => {
address => '5.5.5.5',
broadcast => '6.6.6.6',
netmask => '7.7.7.7',
gateway => '8.8.8.8',
},
);
while (my $line = <DATA>) {
if (my ($interface) = ($line =~ /^interface=(\S+)/)) {
print $line;
if (exists $lookup{$interface}) {
$line = process_interface(\*DATA, $lookup{$interface});
redo;
}
}
else {
print $line;
}
}
sub process_interface {
my ($fh, $lookup) = #_;
my $keys = join '|', sort keys %$lookup;
while (my $line = <DATA>) {
$line =~ s/\A($keys)=.+/$1=$lookup->{$1}/
or return $line;
print $line;
}
return;
}
__DATA__
#
# /etc/rc.conf - Main Configuration for Arch Linux
. /etc/archiso/functions
# stuff
interface=eth0
address=192.168.0.99
netmask=255.255.255.0
broadcast=192.168.0.255
gateway=192.168.0.1
interface=wlan0
address=192.168.0.99
netmask=255.255.255.0
broadcast=192.168.0.255
gateway=192.168.0.1
Output:
#
# /etc/rc.conf - Main Configuration for Arch Linux
. /etc/archiso/functions
# stuff
interface=eth0
address=1.1.1.1
netmask=3.3.3.3
broadcast=2.2.2.2
gateway=4.4.4.4
interface=wlan0
address=5.5.5.5
netmask=7.7.7.7
broadcast=6.6.6.6
gateway=8.8.8.8
The problem is your if/if/if/if/if/else chain, which should be an if/elsif/elsif/elsif/elsif/else chain. The else { print OS $_ } triggers on every line that doesn't match gateway=, including the ones that match interface, address, etc.
Related
When I run the following script from a newly opened PowerShell console, the loop exits so there is clearly a match, but the $matches variable (and thus $matches.PORT) is not populated the first time around. When the script is run again, it is populated.
./ssh.ps1
$BLOCK = { az webapp create-remote-connection --subscription <MY-SUBSCRIPTION> --resource-group <RESOURCE-GROUP> -n <NAME> }
$global:CONNECTION = Start-ThreadJob -ScriptBlock $BLOCK
$done = 0
$match_string = ".*Opening tunnel on port: (?<PORT>\d{1,5})\b.*"
while ($done -lt 1) {
if ($CONNECTION.HasMoreData)
{
$DATA = Receive-Job $CONNECTION 2>&1
if ($DATA -match $match_string)
{
$port = $matches.PORT
Write-Output "Connection open on port $port."
$done = 1
}
}
}
Write-Output "Loop ended."
exit
Output in the PowerShell console is:
PS <LOCAL-DIR>> ./ssh
Connection open on port .
Loop ended.
PS <LOCAL-DIR>> ./ssh
Connection open on port 63182.
Loop ended.
By contrast, when I try running the following script, $matches is populated the first time it is run.
./match.ps1
$string1 = "hello, hello, you big beautiful world of wonder!"
$match_str = ".*\b(?<gotcha>world)\b.*"
$done = 0
while ($done -lt 1)
{
if ($string1 -match $match_str)
{
write-output "Matches:"
write-output $matches
$done = 1
}
}
Output:
PS <LOCAL-DIR>> ./match
Matches:
Name Value
---- -----
gotcha world
0 hello, hello, you big beautiful world of wonder!
If anyone can fathom why the text is matched in the first script without $matches being populated I would be incredibly grateful.
P.S.
The script existing after the loop is just for investigative purposes and not what my code will actually do.
P.P.S.
For reference, the output from az webapp create-remote-connection, after a delay whilst connecting, is:
Verifying if app is running....
App is running. Trying to establish tunnel connection...
Opening tunnel on port: 63341
SSH is available { username: root, password: Docker! }
Ctrl + C to close
(The port varies each time.)
If the automatic $Matches variable isn't populated after a -match operation, the implication is that the LHS operand was a collection rather than a single string.
Therefore, loop over the value of $DATA and match each line individually:
foreach ($line in $DATA) {
if ($line -match $match_string)
{
$port = $matches.PORT
"Connection open on port $port."
$done = 1
break
}
}
By design:
$Matches is only populated if the LHS is a string (scalar).
With a collection (array) as the LHS, -match - as many comparison operators do - acts as a filter and returns the (potentially empty) sub-array of matching elements.
Any prior $Matches value is preserved if either a given string-scalar -match operation happens not to find a match or its LHS is a collection.
I am trying to remove the old files in a dir if the count is more than 3 over SSH
Kindly suggest how to resolve the issue.
Please refer the code snippet
#!/usr/bin/perl
use strict;
use warnings;
my $HOME="/opt/app/latest";
my $LIBS="${HOME}/libs";
my $LIBS_BACKUP_DIR="${HOME}/libs_backups";
my $a;
my $b;
my $c;
my $d;
my $command =qq(sudo /bin/su - jenkins -c "ssh username\#server 'my $a=ls ${LIBS_BACKUP_DIR} | wc -l;my $b=`$a`;if ($b > 3); { print " Found More than 3 back up files , removing older files..";my $c=ls -tr ${LIBS_BACKUP_DIR} | head -1;my $d=`$c`;print "Old file name $d";}else { print "No of back up files are less then 3 .";} '");
print "$command\n";
system($command);
output:
sudo /bin/su - jenkins -c "ssh username#server 'my ; =ls /opt/app/latest/libs_backups | wc -l;my ; =``;if ( > 3); { print " Found More than 3 back up files , removing older files..";my ; =ls -tr /opt/app/latest/libs_backups | head -1;my ; =``;print "Old file name ";}else { print "No of back up files are less then 3 .";} '"
Found: -c: line 0: unexpected EOF while looking for matching `''
Found: -c: line 1: syntax error: unexpected end of file
If you have three levels of escaping, you're bound to get it wrong if you do it manually. Use String::ShellQuote's shell_quote instead.
Furthermore, avoid generating code. You're bound to get it wrong! Pass the necessary information using arguments, the environment or some other channel of communication instead.
There were numerous errors in the interior Perl script on top of the fact that you tried to execute a Perl script without actually invoking perl!
#!/usr/bin/perl
use strict;
use warnings;
use String::ShellQuote qw( shell_quote );
my $HOME = "/opt/app/latest";
my $LIBS = "$HOME/libs";
my $LIBS_BACKUP_DIR = "$HOME/libs_backups";
my $perl_script = <<'__EOI__';
use strict;
use warnings;
use String::ShellQuote qw( shell_quote );
my ($LIBS_BACKUP_DIR) = #ARGV;
my $cmd = shell_quote("ls", "-tr", "--", $LIBS_BACKUP_DIR);
chomp( my #files = `$cmd` );
if (#files > 3) {
print "Found more than 3 back up files. Removing older files...\n";
print "$_\n" for #files;
} else {
print "Found three or fewer backup files.\n";
}
__EOI__
my $remote_cmd = shell_quote("perl", "-e", $perl_script, "--", $LIBS_BACKUP_DIR);
my $ssh_cmd = shell_quote("ssh", 'username#server', "--", $remote_cmd);
my $local_cmd = shell_quote("sudo", "su", "-c", $ssh_ccmd);
system($local_cmd);
I created a new file and handling the dir check and deletion logic , scp file to remote server and executing in remote server , after completion removing the file.
#!/usr/bin/perl
use strict;
use warnings;
use File::Basename;
use File::Path;
use FindBin;
use File::Copy;
my $HOME="/opt/app/test/latest";
my $LIBS_BACKUP_DIR="${HOME}/libs_backups";
my $a="ls ${LIBS_BACKUP_DIR} | wc -l";
my $b=`$a`;
my $c="ls -tr ${LIBS_BACKUP_DIR} | head -1";
my $d=`$c`;
chomp($d);
print " count : $b\n";
if ($b > 3)
{
print " Found More than 3 back up files , removing older files..\n";
print "Old file name $d\n";
my $filepath="${LIBS_BACKUP_DIR}/$d";
rmtree $filepath;
}
else
{
print "No of back up files are less then 3 .\n";
}
I am newbie in Perl programming and currently trying to use Net::OpenSSH module in my code, my new code as below which the task is to run multiple command in remote server,
Code as below::
---
---
foreach $s (#servers) {
my $ssh = Net::OpenSSH->new("$username\#$s", timeout=>30);
$ssh->error and die "Unable to connect: " . $ssh->error;
print "Connected to $s\n";
my $fh = $ssh->capture("df -k /home/ | tail -1") or die "Unable to run command\n";
my #df_arr = split(/\s+/, $fh);
print "$s: Disk space /home/ = $df_arr[3] \n";
my $fh1 = $ssh->capture("svmon -G -O unit=GB | grep memory") or die "Unable to run command\n";
my #sv_arr = split(/\s+/, $fh1);
print "$s: Free memory = $sv_arr[3] \n\n";
close $fh;
undef $ssh;
}
----
----
This code is not so nice since I plan to make it more simplify and reduce a line as many as possible.
Does there are any technique's or methods that I can use to simplify this code?
our way to make it happen in this way:
sub ssh_connect($username, $password)
$ssh = ssh_connect($username, $password)
sub ssh_execute($ssh, $command_str)
there are too much duplicated code in your origin code, maybe you can put them into a subroutine and reuse it.
Hello I have this in a file, multiple lines and from them I want to be able to get the User name and the version he's using.
File
<W>2016-06-25 00:27:30.577 1 => <4:(-1)> Client version 1.2.10 (Win: 1.2.10)
<W>2016-06-25 00:27:30.635 1 => <4:[AAA] User1(1850)> Authenticated
<W>2016-06-25 00:27:30.635 1 => <2:(-1)> Client version 1.2.16 (Win: 1.2.16)
<W>2016-06-25 00:27:30.687 1 => <2:[AAA] User2(942)> Authenticated
Outpout wanted
4 : User1 : 1.2.10
2 : User2 : 1.2.16
So the datas for one client is on 2 lines.
The first line get the version number.
The second line the user name.
I noticed that both lines have a match ID, in my example the user1 line match ID is 4: and 2: for the second user.
So I started with something like this, but don't really work as intended and creating a second read to find the second line in the entire file is too much / not optimized.
Perl Script
#!/usr/bin/perl
use strict;
use warnings;
my $file = 'mylogfile.log';
open (my $fl, '<:encoding(UTF-8)', $file)
or die 'File not found';
while (my $row = <$fl>) {
if ($row =~ m/\<(\d+).*\>\sclient\sversion\s(\d+.\d+.\d+)\s/i) {
my $id = $1;
my $vers = $2;
while (my $row1 = <$fl>) {
if ($row1 =~ m/\<$id\:(.+)\(\d+\)\>/i) {
my $name = $1;
print "$id : $name : $vers\n";
}
}
}
}
If any perl guru have an idea, thanks! :-)
I see in your log file that timestamps of corresponding rows are different.
So, I suppose, when two users log in at the same time, log records could get interspersed, for example:
<W>2016-06-25 00:27:30.577 1 => <4:(-1)> Client version 1.2.10 (Win: 1.2.10)
<W>2016-06-25 00:27:30.635 1 => <2:(-1)> Client version 1.2.16 (Win: 1.2.16)
<W>2016-06-25 00:27:30.635 1 => <4:[AAA] User1(1850)> Authenticated
<W>2016-06-25 00:27:30.687 1 => <2:[AAA] User2(942)> Authenticated
If this is the case, I would suggest using a hash to remember ids:
use strict;
use warnings;
my $file = 'mylogfile.log';
open (my $fl, '<:encoding(UTF-8)', $file)
or die 'File not found';
my %ids;
while (my $row = <$fl>) {
if ($row =~ m/\<(\d+).*\>\sclient\sversion\s(\d+.\d+.\d+)\s/i) {
my ($id,$vers)=($1,$2);
$ids{$id}=$vers;
}
elsif ($row =~ m/\<(\d+)\:(.+)\(\d+\)\>.*authenticated/i) {
if (defined $ids{$1}) {
print "$1 : $2 : $ids{$1}\n";
delete $ids{$1};
}
}
}
I don't know much about perl, but can provide some idea:
login= map();
while( row=readrow())
{
if(match(id version))
login[$1]=$2
else
if(match(id username userid ))
{
print "user: ", $2, "version:",login[$1], "userid: $3", "sessionid: ", $1
delete login[$1]
}
}
Running your code gave me the result
4 : [AAA] User1 : 1.2.10
Your second regular expression is capturing the bracketed letters and the user name. This isn't what your desired output looks like.
The second while loop exhausts the remainder of the file. And, this isn't what you want to do.
Here is a program that will produce the output you want. (I created a file at the top of the program. You would not use this but instead, open your file 'mylogfile.log' just as you did in your code).
#!/usr/bin/perl
use strict;
use warnings;
open my $fh, '<', \<<EOF;
<W>2016-06-25 00:27:30.577 1 => <4:(-1)> Client version 1.2.10 (Win: 1.2.10)
<W>2016-06-25 00:27:30.635 1 => <4:[AAA] User1(1850)> Authenticated
<W>2016-06-25 00:27:30.635 1 => <2:(-1)> Client version 1.2.16 (Win: 1.2.16)
<W>2016-06-25 00:27:30.687 1 => <2:[AAA] User2(942)> Authenticated
EOF
while (<$fh>) {
if (/<(\d+).+?Client version (\d+\.\d+\.\d+)/) {
my ($id, $vers) = ($1, $2);
# read next line and capture name
if (<$fh> =~ /<$id\S+ ([^(]+)/) {
my $name = $1;
print join(" : ", $id, $name, $vers), "\n";
}
}
}
In my second regular expression, the piece, [^(]+, is called a negated class. It matches non 'left parens' (1 or more times). This matches "User1' and 'User2' in the line of the file.
Update: You can find info about character classes here.
Update2: Looking at wolfrevokcats reply, I see he made a valid observation and his solution is the safer one.
I am actually Monitoring a directory for creation of new files(.log files) these files are generated by some tool and tool writes log entries after sometime of the creation of the same file, During this time file will be empty.
and how can i wait until something is written to the log and reason being based on the log entries i will be invoking different script!,
use strict;
use warnings;
use File::Monitor;
use File::Basename;
my $script1 = "~/Desktop/parser1.pl";
my $scrip2t = "~/Desktop/parser2.pl";
my $dir = "~/Desktop/tool/logs";
sub textfile_notifier {
my ($watch_name, $event, $change) = #_;
my #new_file_paths = $change->files_created; #The change object has a property called files_created,
#which contains the names of any new files
for my $path (#new_file_paths) {
my ($base, $fname, $ext) = fileparse($path, '.log'); # $ext is "" if the '.log' extension is
# not found, otherwise it's '.log'.
if ($ext eq '.log') {
print "$path was created\n";
if(-z $path){
# i need to wait until something is written to log
}else{
my #arrr = `head -30 $path`;
foreach(#arr){
if(/Tool1/){
system("/usr/bin/perl $script1 $path \&");
}elsif(/Tool1/){
system("/usr/bin/perl $script2 $path \&");
}
}
}
}
my $monitor = File::Monitor->new();
$monitor->watch( {
name => $dir,
recurse => 1,
callback => {files_created => \&textfile_notifier}, #event => handler
} );
$monitor->scan;
while(1){
$monitor->scan;
}
Basically i am grepping some of the important information from the logs.
For such formulation of your question, something like this might help you:
use File::Tail;
# for log file $logname
my #logdata;
my $file = File::Tail->new(name => $logname, maxinterval => 1);
while (defined(my $newline = $file->read)) {
push #logdata, $newline;
# the decision to launch the script according to data in #logdata
}
Read more here
You are monitoring just the log file creation. Maybe you could use a sleep function inside the call back sub to wait for the log file been wrote. You could monitor file changes too, because some log files could be extended.