Beefy Boxes and Bandwidth Generously Provided by pair Networks
P is for Practical
 
PerlMonks  

Re^2: Parse a file into a hash

by kazak (Beadle)
on Apr 05, 2012 at 20:21 UTC ( #963733=note: print w/ replies, xml ) Need Help??


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);


Comment on Re^2: Parse a file into a hash
Download Code
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;

    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 } }

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

      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

        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;

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://963733]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others surveying the Monastery: (10)
As of 2015-07-06 16:52 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    The top three priorities of my open tasks are (in descending order of likelihood to be worked on) ...









    Results (77 votes), past polls