Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I am reading the below log file and looking for the word error .If it finds error then it should print some stuff. But it is not printing when there is error.



LOG FILE: 
QA-METS - Checksum log

UID=61110530R
Title=Lecture introductory to the course on anatomy, in the University
+ of Pennsylvania /

FileID=BSE1
Filename=61110530R_000001.jpg
METS: Mimetype=image/jpg Size=1950329 MD5=fb0ff0b498cb6ce79df20fdddd71
+da3f
[Error] Checksum mismatch;   Computed MD5=08141ce3c84cb54d57d40b502331
+2c53

FileID=BSE2
Filename=61110530R_000002.jpg
METS: Mimetype=image/jpg Size=737596 MD5=7b44c390f7279a3f266652a96a5f6
+86d
[Error] Checksum mismatch;   Computed MD5=462db8d6b278f6fdb63f87fd2974
+e7e9

FileID=BSE3
Filename=61110530R_000003.jpg
METS: Mimetype=image/jpg Size=1010181 MD5=8acd6e39a21f0fc18dfb6a54663f
+a472
[Error] Checksum mismatch;   Computed MD5=7e9c7959e3a3b60c4d2f80e089f0
+3f9d

FileID=BSE4
Filename=61110530R_000004.jpg
METS: Mimetype=image/jpg Size=655993 MD5=f655a572365bcea7c878201b7606d
+68a
[Error] Checksum mismatch;   Computed MD5=0fbdfb7ba703e0ad810025135e4e
+8070

FileID=BSE5
Filename=61110530R_000005.jpg
METS: Mimetype=image/jpg Size=838116 MD5=2a055f3579db7f9c583c8cf84afdf
+030
[Error] Checksum mismatch;   Computed MD5=50a8ee3e882b79de5fe8a47be54c
+c478

FileID=BSE6
Filename=61110530R_000006.jpg
METS: Mimetype=image/jpg Size=511383 MD5=8dfa19092cdf0d76bf99eede88fae
+e19
[Error] Checksum mismatch;   Computed MD5=3380c9f79217ba0faee294ab9cff
+db81

FileID=BSE7
Filename=61110530R_000007.jpg
METS: Mimetype=image/jpg Size=881218 MD5=97d8a953cc1b8ab1dff728a8b0814
+6be
[Error] Checksum mismatch;   Computed MD5=37fa1505f9ca13251406658653af
+4439

FileID=BSE8
Filename=61110530R_000008.jpg
METS: Mimetype=image/jpg Size=496683 MD5=638a7f3cb7d2b189751c62c91e018
+d28
[Error] Checksum mismatch;   Computed MD5=d008d5852cfaff6cf14fa0748b5d
+044f

[download]

Current Script 

#!/usr/local/bin/perl

use strict;
use warnings;
use Data::Dumper;

$/ = "";

my @InputFiles = (</usr/mlm/qa/logs/hhl/BATCH*/*/*_checksum.log>);


foreach my $InputFile ( @InputFiles ) {

  print "$InputFile\n";

    my %errors;

    open my $input_fh, '<', $InputFile
      or die "Can't open input file ($InputFile): $!";

    my $uid = <$input_fh>;
    ($uid) = $uid =~ /UID=(\S+)/;

    while ( my $record = <$input_fh> ) {
        my ($md5)      = $record =~ /METS:.+?MD5=(\S+)/;
        my ($filename) = $record =~ /Filename=(\S+)/;
        #my ($error)    = $record =~ /[Error] +MD5=(\S+)/;
        my ($error)    = $record =~ /\Q[Error]\E .+MD5=(\S+)/;

        if ( $error ) {
            $errors{$filename}{md5}      = $md5;
            $errors{$filename}{computed} = $error;
        }
    }
    close $input_fh;

    my $count = keys %errors;


     foreach my $filename ( sort keys %errors ) {
        print join('|', $uid,
                      $filename,
                      $count,
                      $errors{$filename}{md5},
                      $errors{$filename}{computed}
                ),"\n";

[download]

Replies are listed 'Best First'.
Re: LOG FILE HELP IN PERL
by toolic (Bishop) on Jan 19, 2011 at 17:08 UTC
    You didn't show us what you expect to be printed. But, when I fix the compile errors in the code you posted, then run it, I get the following output: 
    ./foo.log
Use of uninitialized value $uid in join or string 
|61110530R_000001.jpg|8|fb0ff0b498cb6ce79df20fdddd71da3f|08141ce3c84cb
+54d57d40b5023312c53
Use of uninitialized value $uid in join or string 
|61110530R_000002.jpg|8|7b44c390f7279a3f266652a96a5f686d|462db8d6b278f
+6fdb63f87fd2974e7e9
Use of uninitialized value $uid in join or string 
|61110530R_000003.jpg|8|8acd6e39a21f0fc18dfb6a54663fa472|7e9c7959e3a3b
+60c4d2f80e089f03f9d
Use of uninitialized value $uid in join or string 
|61110530R_000004.jpg|8|f655a572365bcea7c878201b7606d68a|0fbdfb7ba703e
+0ad810025135e4e8070
Use of uninitialized value $uid in join or string 
|61110530R_000005.jpg|8|2a055f3579db7f9c583c8cf84afdf030|50a8ee3e882b7
+9de5fe8a47be54cc478
Use of uninitialized value $uid in join or string 
|61110530R_000006.jpg|8|8dfa19092cdf0d76bf99eede88faee19|3380c9f79217b
+a0faee294ab9cffdb81
Use of uninitialized value $uid in join or string 
|61110530R_000007.jpg|8|97d8a953cc1b8ab1dff728a8b08146be|37fa1505f9ca1
+3251406658653af4439
Use of uninitialized value $uid in join or string 
|61110530R_000008.jpg|8|638a7f3cb7d2b189751c62c91e018d28|d008d5852cfaf
+f6cf14fa0748b5d044f

    [download]
    Update: At AM's request, here is a compilable version of the OP's code (2 extra curlies at the end): 
    #!/usr/local/bin/perl

use strict;
use warnings;
use Data::Dumper;

$/ = "";

my @InputFiles = (</usr/mlm/qa/logs/hhl/BATCH*/*/*_checksum.log>);


foreach my $InputFile ( @InputFiles ) {

  print "$InputFile\n";

    my %errors;

    open my $input_fh, '<', $InputFile
      or die "Can't open input file ($InputFile): $!";

    my $uid = <$input_fh>;
    ($uid) = $uid =~ /UID=(\S+)/;

    while ( my $record = <$input_fh> ) {
        my ($md5)      = $record =~ /METS:.+?MD5=(\S+)/;
        my ($filename) = $record =~ /Filename=(\S+)/;
        #my ($error)    = $record =~ /[Error] +MD5=(\S+)/;
        my ($error)    = $record =~ /\Q[Error]\E .+MD5=(\S+)/;

        if ( $error ) {
            $errors{$filename}{md5}      = $md5;
            $errors{$filename}{computed} = $error;
        }
    }
    close $input_fh;

    my $count = keys %errors;


     foreach my $filename ( sort keys %errors ) {
        print join('|', $uid,
                      $filename,
                      $count,
                      $errors{$filename}{md5},
                      $errors{$filename}{computed}
                ),"\n";
     
     }
}

    [download]
[reply]
[d/l]
[select]

      Not sure why the same above script is not printing the output for me.

[reply]
[reply]

      If possible can you post the code fixed code here.

[reply]
Re: LOG FILE HELP IN PERL
by JavaFan (Canon) on Jan 19, 2011 at 17:49 UTC 
    my $uid = <$input_fh>;
($uid) = $uid =~ /UID=(\S+)/;

    [download]
    That tries to find a UID in the first paragraph of the file. However, the first paragraph is the line starting with QA-METS. You want to skip the first paragraph, and do this match against the second.
[reply]
[d/l]
[select]
Re: LOG FILE HELP IN PERL
by tilly (Archbishop) on Jan 19, 2011 at 17:12 UTC
    Your bug is that you are setting $md5 on every single line of input. So when you hit an error line, you no longer know the md5 from the line before.

    To fix it you need to define $md5 outside of the while loop that reads through the file, and then inside the file you need to set it only if the record matched. That way it will get set when you encounter that line, and it will still be set on the error line.

    (Incidentally you left two closing braces off of your cut and paste of your script.)

    Edit: JavaFan is correct. I'd missed paragraph mode which does fix that potential problem. The cause of the undef warnings is that $UID is not populated, because the UID line is on the second paragraph, not the first. If you add another <$input_fh>; that warning goes away. (This is very, very fragile logic. But it seems to work.)

    If there is still no output, then I would advise checking whether it is looking for the files in the right place.

[reply]
[d/l]
      Your bug is that you are setting $md5 on every single line of input. So when you hit an error line, you no longer know the md5 from the line before.
      Except that he has $/ = "";, which makes it read paragraph by paragraph.
[reply]
[d/l]

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