Complex Hash of Hashes (New to them)

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

First time poster and new to hash of hashes. I am trying to learn how to navigate around hash of hashes. I have used XML::Simple::XMLin to import a NetCONF (XML) file to $xml. I am trying to print specific parts of the hash, but not with much success using:

print $xml->{'bgp-information'}->{'bgp-peer'}{[0]}->{'peer-address'};

I am also trying to figure out how I can while loop all the "peer-address" entries (e.g. 1.1.1.1, 2.2.2.2, 3.3.3.3) to print entries within. Any input would be greatly appreciated.

Thanks,
~Ethan

$VAR1 = {
          'xmlns' => 'urn:ietf:params:xml:ns:netconf:base:1.0',
          'bgp-information' => {
                               'group-count' => '3',
                               'xmlns' => 'http://xml.juniper.net/juno
+s/8.0R3/junos-routing',
                               'bgp-rib' => {
                                            'total-external-prefix-cou
+nt' => '222224',
                                            'damped-prefix-count' => '
+0',
                                            'active-prefix-count' => '
+223534',
                                            'pending-prefix-count' => 
+'0',
                                            'suppressed-internal-prefi
+x-count' => '0',
                                            'active-internal-prefix-co
+unt' => '16579',
                                            'name' => 'inet.0',
                                            'junos:style' => 'brief',
                                            'total-internal-prefix-cou
+nt' => '69811',
                                            'suppressed-external-prefi
+x-count' => '0',
                                            'history-prefix-count' => 
+'0',
                                            'received-prefix-count' =>
+ '292035',
                                            'active-external-prefix-co
+unt' => '206955',
                                            'suppressed-prefix-count' 
+=> '0',
                                            'bgp-rib-state' => 'BGP re
+start is complete',
                                            'total-prefix-count' => '2
+92035'
                                          },
                               'peer-count' => '3',
                               'bgp-peer' => [
                                             {
                                               'peer-address' => '1.1.
+1.1',
                                               'bgp-rib' => {
                                                            'received-
+prefix-count' => '69811',
                                                            'active-pr
+efix-count' => '16579',
                                                            'suppresse
+d-prefix-count' => '0',
                                                            'name' => 
+'inet.0'
                                                          },
                                               'peer-state' => {
                                                               'junos:
+format' => '16579/69811/0        0/0/0',
                                                               'conten
+t' => 'Established'
                                                             },
                                               'peer-as' => '1000',
                                               'junos:style' => 'terse
+',
                                               'heading' => 'Peer     
+          AS      InPkt     OutPkt    OutQ   Flaps Last Up/Dwn State|
+#Active/Received/Damped...',
                                               'elapsed-time' => {
                                                                 'juno
+s:seconds' => '8579868',
                                                                 'cont
+ent' => '14w1d7h'
                                                               },
                                               'route-queue-count' => 
+'0',
                                               'flap-count' => '0',
                                               'input-messages' => '41
+69581',
                                               'output-messages' => '8
+472027'
                                             },
                                             {
                                               'peer-address' => '2.2.
+2.2',
                                               'bgp-rib' => {
                                                            'received-
+prefix-count' => '1',
                                                            'active-pr
+efix-count' => '1',
                                                            'suppresse
+d-prefix-count' => '0',
                                                            'name' => 
+'inet.0'
                                                          },
                                               'peer-state' => {
                                                               'junos:
+format' => '1/1/0                0/0/0',
                                                               'conten
+t' => 'Established'
                                                             },
                                               'peer-as' => '2000',
                                               'junos:style' => 'terse
+',
                                               'elapsed-time' => {
                                                                 'juno
+s:seconds' => '8580144',
                                                                 'cont
+ent' => '14w1d7h'
                                                               },
                                               'route-queue-count' => 
+'0',
                                               'flap-count' => '0',
                                               'input-messages' => '28
+6000',
                                               'output-messages' => '2
+85903'
                                             },
                                             {
                                               'peer-address' => '3.3.
+3.3',
                                               'bgp-rib' => {
                                                            'received-
+prefix-count' => '222223',
                                                            'active-pr
+efix-count' => '206954',
                                                            'suppresse
+d-prefix-count' => '0',
                                                            'name' => 
+'inet.0'
                                                          },
                                               'peer-state' => {
                                                               'junos:
+format' => '206954/222223/0      0/0/0',
                                                               'conten
+t' => 'Established'
                                                             },
                                               'peer-as' => '3000',
                                               'junos:style' => 'terse
+',
                                               'elapsed-time' => {
                                                                 'juno
+s:seconds' => '7166196',
                                                                 'cont
+ent' => '11w5d22h'
                                                               },
                                               'route-queue-count' => 
+'0',
                                               'flap-count' => '2',
                                               'input-messages' => '84
+23202',
                                               'output-messages' => '2
+38785'
                                             }
                                           ],
                               'down-peer-count' => '0'
                             },
          'xmlns:junos' => 'http://xml.juniper.net/junos/8.0R3/junos'
        };
[download]

Comment on Complex Hash of Hashes (New to them) Download Code

Replies are listed 'Best First'.
Re: Complex Hash of Hashes (New to them) by FunkyMonk (Bishop) on Jul 24, 2007 at 09:13 UTC
The `bgp-peer` entry is an array of hashes. You can access them in a similar way that you access a hash of hashes (which you seem to have got the hang of): hash of hash - $xml->{'bgp-information'}->{'bgp-peer'} hash of arrays - $xml->{'bgp-information'}->{'bgp-peer'}->[0] Have you read the Perl data structures cookbook? And have a look at Data::Dumper. It's invaluable when dealing with deeply nested structures.	[reply] [d/l]
Re: Complex Hash of Hashes (New to them) by planetscape (Chancellor) on Jul 24, 2007 at 12:57 UTC
You might find How can I visualize my complex data structure? helpful. HTH, planetscape	[reply]
Re: Complex Hash of Hashes (New to them) by citromatik (Curate) on Jul 24, 2007 at 10:28 UTC
I am trying to print specific parts of the hash, but not with much success using: print $xml->{'bgp-information'}->{'bgp-peer'}{[0]}->{'peer-address'}; `print $VAR1->{'bgp-information'}->{'bgp-peer'}->[0]->{'peer-address'}, +"\n";` [download] Outputs: `1.1.1.1` [download] I am also trying to figure out how I can while loop all the "peer-address" entries (e.g. 1.1.1.1, 2.2.2.2, 3.3.3.3) to print entries within `for (@{$VAR1->{'bgp-information'}->{'bgp-peer'}}){ print $_->{'peer-address'},"\n"; }` [download] Outputs: `1.1.1.1 2.2.2.2 3.3.3.3` [download] citromatik	[reply] [d/l] [select]
Re: Complex Hash of Hashes (New to them) by leocharre (Priest) on Jul 24, 2007 at 13:04 UTC
Not sure if this applies. But you remind me of something. I used to have quite heavy complicated hashes, and I could make creepy calls to places like @{ $master{Files}->{$rel_path}->{author}} , etc.. I was comfortable because I knew what the structure was. However.. coming back to code like that months later was torture. Wait, I need to expand on that; coming back to code like that is like fixing html markup for a living using only paper and pencil. What's curious to me is that all that stopped when I started taking to object oriented programming. Since then I don't seem to have complex hierarchies of data that way. It seems I create little parts of them on the fly- as they are requested.	[reply]