An example of access log parsing

gistfile1.pl

#!/usr/bin/env perl
use strict;
use warnings;

my %rank_hour; # Access per hour
my %rank_file; # Access per file

open LOG, "<", "access_log";     # Open log file
open CSV, ">", "access_log.csv"; # Open CSV output file

while( <LOG> ) {
  $_ =~ /^(.+) .+ .+ \[.+\/.+\/.+:(.+):(.+):(.+) .+\] ".+ (.+) .+" .+ .+ ".+" ".+"$/; # Parse line
  my $ip = $1; # Accessor's IP address
  my ( $hour, $min, $sec ) = ( $2, $3, $4 ); # The time
  my $file = $5; # The file
  $rank_hour{$hour}++; # Count the access per hour
  $rank_file{$file}++; # Count the access per file
  print CSV "$ip,$hour:$min:$sec,$file\n"; # Print out CSV
}

print "Access ranking per hour:\n";
foreach my $hour ( sort{$rank_hour{$b} <=> $rank_hour{$a}}keys %rank_hour ) { # Sort the access per hour
  print "$hour: $rank_hour{$hour}\n";
}

print "Access ranking per file:\n";
foreach my $file ( sort{$rank_file{$b} <=> $rank_file{$a}}keys %rank_file ) { # Sort the access per file
  print "$file: $rank_file{$file}\n";
}