Data Structure confusion...

Spoon71 has asked for the wisdom of the Perl Monks concerning the following question:

I'm trying to use a Perl module (Opsview::REST) it wants to use a data structure that looks like below. I'm properly confused as to what this is hash of hashes or whatever...

                       'hostattributes' => [
                                              {
                                                'value' => 'some value
+1',
                                                'name' => 'URL',
                                                'arg2' => undef,
                                                'arg4' => undef,
                                                'arg1' => 'someurl.com
+',
                                                'arg3' => undef
                                              },
                                              {
                                                'arg3' => undef,
                                                'arg1' => 'someurl..co
+m',
                                                'name' => 'URL',
                                                'arg4' => undef,
                                                'arg2' => undef,
                                                'value' => 'some value
+ 2'
                                              }
                                            ],
[download]

I need to create it programatically as I need to read and parse data to create multiple blocks (which is no problem) then once created I need to pass it into the Opsview::Rest piece as below

my $host = $ops->create_or_update_host(
    ip                  => 'nodename.com',
    name                => "Name",
    hostgroup           => { name => 'RDG - Prod Services' },
    hosttemplates        => [ { 'ref' => '/rest/config/hosttemplate/94
+', 'name' => 'AA-RDG-Pseudo-services' } ],
    hostattributes        => PASS HERE,
    notification_period => { name => 'RDG-24x7-Minus-Bounce' }
);
[download]

I'm an occasional Perl programmer so this may be simple to some but I'm bloody confused, any help welcome

Comment on Data Structure confusion... Select or Download Code

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Re: Data Structure confusion... by talexb (Chancellor) on Apr 26, 2016 at 15:47 UTC
Here's a quick primer on reading Perl data structures: `'something' => (any data structure)` - a hash key/value pair. `[ (a list of things) ]` - an arrayref, `{ key => value, .. }` - a hashref `( key => value, .. )` - a hash So, using those rules, your `'hostattributes'` key has a value of an arrayref that contains two elements, each of which is a hashref, each of which contains five key/value pairs. Because this is a hash, the keys can appear in any order. Alex / talexb / Toronto Thanks PJ. We owe you so much. Groklaw -- RIP -- 2003 to 2013.	[reply] [d/l] [select]
Re: Data Structure confusion... by AnomalousMonk (Archbishop) on Apr 26, 2016 at 13:52 UTC
Not specifically responsive to your question, but see Perl Data Structures Cookbook for general info on this topic. Give a man a fish: `<%-{-{-{-<`	[reply] [d/l]
Re: Data Structure confusion... by stevieb (Canon) on Apr 26, 2016 at 13:49 UTC
Welcome to the Monastery, Spoon71! What you have there is an array of hashes (AoH), contained within an existing hash, referenced by a `hostattributes` key. To help you create this structure, we'll need a small sample of your input data.	[reply] [d/l]
Re: Data Structure confusion... by NetWallah (Canon) on Apr 26, 2016 at 16:55 UTC
I would suggest building the required structure this way: my @hostatt; push @hostatt, # Info for First host { 'value' => 'some value1', 'name' => 'URL', 'arg2' => undef, 'arg4' => undef, 'arg1' => 'someurl.com', 'arg3' => undef }; push @hostatt, # Info for Second host { 'value' => 'some value2', 'name' => 'URL2', 'arg2' => undef, 'arg4' => undef, 'arg1' => 'someur2.com', 'arg3' => undef }; #Finally, assign this to the main structure my $host = $ops->create_or_update_host( ip => 'nodename.com', name => "Name", hostgroup => { name => 'RDG - Prod Services' }, hosttemplates => [ { 'ref' => '/rest/config/hosttemplate/94 +', 'name' => 'AA-RDG-Pseudo-services' } ] +, hostattributes => \@hostatt, # <<< HERE <<<<< notification_period => { name => 'RDG-24x7-Minus-Bounce' } ); [download] This is not an optical illusion, it just looks like one.	[reply] [d/l]
Re^2: Data Structure confusion... by Spoon71 (Initiate) on Apr 27, 2016 at 08:17 UTC
Perfect this works!!!! Thanks	[reply]