Pattern matching in perl & assigning - perl

Question

I need to search for a particular string in a file and then assign it to a variable, example: in the file content it is written as CURRENT_RUN_ID=1636, so I need to search for string CURRENT_RUN_ID and assign its given value i.e. 1636 toa variable sayrunvar`, for this I tried below given, but it doesn't seem to be working, can you correct me here?
opendir(DAPATH,$sDAPATH) or die "Can't open $sDAPATH: $!";
print OUTLOG "\nfound da path : $sDAPATH\n";
my #adirs = readdir(DAPATH);
print OUTLOG "Starting capturing DA\n";
my $da = glob "*$runVar.csv*";
print OUTLOG "Assigned DA";
closedir(DAPATH);
}

Answer 1

It is not matching because you are giving spaces at if (/CURRENT_RUN_ID = \s*(.*)/) in the match.It is searching for spaces in the string.
The pattern what you are trying to match will match CURRENT_RUN_ID = 1636 string, notice the spaces between CURRENT_RUN_ID and = and after =. If there is match then the no of spaces in the pattern should be exactly same as the no of spaces in the string.
There is space between CURRENT_RUN_ID and = and also after =.
Better remove the faulty spaces and make the space optional using \s* try this:
if (/CURRENT_RUN_ID\s*=\s*(.*)/){
my $runvar = $1;
print "$runvar \n";
}
EDIT:
As per your requirement I changed your script as(I am not writing to file):
#!/usr/bin/perl
use strict;
use warnings;
open my $fh, '<', 'file' or die "unable to open file : $! \n";
my $runVar="";
while(<$fh>){
if (/CURRENT_RUN_ID\s*=\s*(.*)/){
print "we can now assign run id\n";
$runVar = $1;
print "assigned current run id to variable\n";
}
else {
print "run id not assigned\n";
}
}
close($fh);

Answer 2

Here you are not matching any of the lines while performing the pattern matching in line 18. And even you can reduce few repetitive steps in the code.
But for your convenience I have used your program.
#!C:\Strawberry\perl\bin
use strict;
use warnings;
my $sSuccessString = "CURRENT_RUN_ID";
open(LOG,"$slogfile") or die("Can't open $slogfile\n");
my $sLines;
{
local $/ = undef;
$sLines=<LOG>;
}
if($sLines =~ m/$sSuccessString/){
open(OUTLOG, ">>test.txt");
print OUTLOG "found current run id in log\n";
print OUTLOG "it is found in log as : $sSuccessString \n";
#if ($sLines =~ m/(CURRENT_RUN_ID=.*)/i) {
#print OUTLOG "<p>" . $1 . "<\/p>\n";
#In below line you need to match the pattern with the line.
if ($sLines=~/CURRENT_RUN_ID=(.*)/){
print OUTLOG "we can now assign run id\n";
my $runVar = $1;
print "$runVar\n";
print OUTLOG "assigned current run id to variable\n";
}
else {
print "run id not assigned\n";
}
}
I have copied your log file content to one of my text file (prog.txt) on my desktop and ran the script. Please see the output.
#!C:\Strawberry\perl\bin
use strict;
use warnings;
my $sSuccessString = "CURRENT_RUN_ID";
open(LOG,"Prog.txt") or die("Can't open text file\n");
my $sLines;
{
local $/ = undef;
$sLines=<LOG>;
}
if($sLines =~ m/$sSuccessString/){
open(OUTLOG, ">>test.txt");
print OUTLOG "found current run id in log\n";
print OUTLOG "it is found in log as : $sSuccessString \n";
#if ($sLines =~ m/(CURRENT_RUN_ID=.*)/i) {
#print OUTLOG "<p>" . $1 . "<\/p>\n";
if ($sLines=~/CURRENT_RUN_ID=(.*)/){
print OUTLOG "we can now assign run id\n";
my $runVar = $1;
print "$runVar\n";
print OUTLOG "assigned current run id to variable\n";
}
else {
print "run id not assigned\n";
}
}
OUTPUT:
C:\Users\hclabv\Desktop>perl run1.pl
1637
And my log file (test.txt) where we are capturing the logs while running script is as below.
found current run id in log
it is found in log as : CURRENT_RUN_ID
we can now assign run id
assigned current run id to variable
For getting runVar.csv file from desired directory, I have added the below piece of code with in the if loop
opendir(DAPATH,"C:/Users/hclabv/Desktop/Scripting/files") or die "Can't open DAPATH: $!";
print OUTLOG "\nfound da path : DAPATH\n";
my #adirs = readdir(DAPATH);
print "csv files #adirs\n";
print OUTLOG "Starting capturing DA\n";
my $csvfile = "$runVar.csv";
foreach my $adirs (#adirs) {
if ($adirs eq $csvfile) {
print "file found\n";
my $da = $adirs;
print "csv file is $da\n";
}
print OUTLOG "Assigned DA";
close(DAPATH);
}