in reply to Re: Parse a file into a hash
in thread [Resolved] Parse a file into a hash

Thank you for your reply, yes it helped a bit. File I need to parse is a .csv file with a fileds that must be converted to an ACLs, there are two fields: User name , asset name . One user can have either one or multiple asset names, but user name is unique. So unique user name I'm trying to use as a key and asset names I trying to use as a values of these unique keys. So one user John Doe may have either one asset name: John Doe = { "KJhkh23"} or multiple: John Doe = { "KJhkh23", "0jUfh4631",....."N"}. File was populated manually and irregulary, I mean in "User Name" field we may have one name "John Doe" but in field " Asset name" we may have a column of values. The problem is to define a first field as a key(John Doe) and the second as a value (KJhkh23), and if on the next line we can't detect a key, assume that this asset belongs to last available key (John Doe) . I'm new to perl so this code may look like a total mess for coders. 
#!/usr/bin/perl -w
use warnings;
use strict;

my @tmp;

### Start Configuration
my $src_file = "Servers.csv";
### End Configuration

my %stack = ();
my $current_key = undef;
my $current_value = undef;

open( SRC, "<", $src_file  );

while (<SRC>) {
       chomp;
        s/#.*//;
        s/\"//g;
        s/\;/\-/;
        push @tmp, $_ if $_ =~ m/^\;/ and next;
        my ($key,$value) = split /\-/, $_;
        push @tmp, $value;

        if (defined $key) {
           $current_key = $key;
            push @tmp, $value;
           $stack{$current_key} = @tmp;
}

close(SRC);

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Re^3: Parse a file into a hash
by aaron_baugher (Curate) on Apr 05, 2012 at 22:19 UTC

    You should probably show us some sample data, so we can tell what "can't detect a key" means. But in general, you're talking about creating a hash of arrays. So for every key/value pair, you'll want to do something like this: 

    push @{$stack{$key}}, $value;

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    That pushes the value onto the array referenced by the key within the hash. Later, you'll be able to go through them with:

    for my $key (keys %stack){
  for my $value (@{$stack{$key}}){
    # do stuff with $key and $value
  }
}

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    Aaron B.
    My Woefully Neglected Blog, where I occasionally mention Perl.

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      Thanks for your reply. I don't know how to preserve initial format of the file here, so I'll replace empty cells of.csv with null.

      Username; Asset Name

      Corinna Mayer;JKDef4574

      Janek Huska;NAdf8f48g5

      Eric Shtits;JSd5345kPFl

      null;A878rfgP56

      null;KDLefrtgt

      Erik Fisher;UiO8trve

      As you can see Eric Shtits owns 3 asset names in according to this .csv file, so two fields that supposed to be keys are empty.And I need to implement a solution that will be able to detect that all three asset names belong to one person. Regards, Kazak
[reply]

        hi check if this code works or not its not tested. 

        my ($key,$val,$keyprev);
open(fh,'< file.txt');
while (<fh>){
    $keyprev=$key;
    ($key,$val)=split /\;/, $_;
    $key=$keyprev if($key eq"");
    print "$key :: $val\n";
}
close fh;

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