parsing JSON for specific entries

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

Hello wise monks.

I have a very large json formatted file that I am trying to extract specific values from. The json file looks like such:

{ "Content_ID" : { "CNBP_021687" : { "Title" : "Molecule of the Week -
+ Pyruvic Acid",
          "Type" : "Article",
          "Web Extension" : "doc",
          "WebSite" : "PublicWebSite",
          "WebSiteSection" : "PublicWebSite:841"
        },
      "CNBP_021688" : { "Title" : "STEM Education Coalition Supports V
+olunteer Service Legislation",
          "Type" : "Article",
          "Web Extension" : "pdf",
          "WebSite" : "PublicWebSite",
          "WebSiteSection" : "PublicWebSite:1892"
        },
      "CNBP_021691" : { "Title" : "WCC Lectureship Award",
          "Type" : "Article",
          "Web Extension" : "doc",
          "WebSite" : "PublicWebSite",
          "WebSiteSection" : "PublicWebSite:1367"
        },
[download]

And my script looks like such:

 #!c:/strawberry/perl/bin/perl.exe 
use JSON;
use Data::Dumper; 
use warnings;
use strict;
use utf8;
use URI::Escape; 
my $text; 
my $json ="";  
my $object = "";
my $item = "";

sub extract_json {
    my $file = shift;
    local $/; #enable slurp
      open my $fh, "<", "$file";  
      $json = <$fh>;     
    return $json;
}

my $jobj = extract_json('C:\Temp3\articlePaagesJson.txt');

use Encode;
$object = JSON::XS->new->decode (decode "UTF-8", $jobj);
 # print Dumper $object


foreach $item (@{$object->{Content_ID}} ){
    print " do nothing \n";
};
[download]

When I use data dumber the values print but I keep getting an error Not an ARRAY reference at

I am trying to exctract the content ID the title and the web extension if that helps at all. I keep trying everything and anything I see online and on the board but nothing is working.

Any help would be greatly appreciated

Comment on parsing JSON for specific entries Select or Download Code

Replies are listed 'Best First'.
Re: parsing JSON for specific entries by suaveant (Parson) on Aug 01, 2012 at 19:04 UTC
{ denotes a hash, [ denotes array, just like in Perl. You are trying to iterate through $object->{Content_ID} by dereferencing it as an ARRAY but it is a hash, with keys CNBP_021687, CNBP_021688 and CNBP_021691. The correct way to iterate would be: `foreach $key (keys %{$object->{Content_ID}} ){ my $item = $object->{Content_ID}{$key}; print " do nothing \n"; };` [download] - Ant - Some of my best work - (1 2 3)	[reply] [d/l]
Re: parsing JSON for specific entries by linuxkid (Sexton) on Aug 02, 2012 at 01:29 UTC
just out of curoisty, could you use YAML? --linuxkid imrunningoutofideas.co.cc	[reply]


No such thing as a small change
	PerlMonks

parsing JSON for specific entries

--linuxkid