in reply to Need help with node names for creating header line

Try

#!/usr/bin/perl
use strict;
use warnings;
use XML::Twig;

my $header='u_ci_id,u_display_name,name,fqdn,ip_address,mac_address';
my $field = $ARGV[0] || 'u_ci_id';
my $input_xml = do { local $/; <DATA> };

my $twig = new XML::Twig;
$twig->xparse($input_xml);
my $root = $twig->root();

my @data = ();
my @cols = split ',',$header;
unshift @cols, $field; # added for sort

for my $record ($root->children) {
  push @data,[ map { $record->first_child($_)->text } @cols];
}

my @sorted = sort { $b->[0] cmp $a->[0] } @data;
print $header."\n";
for (@sorted){
  print join ',',@$_[1..$#cols]; # exclude sort col
  print "\n";
}

__DATA__
<?xml version="1.0" encoding="UTF-8"?>
<response>
 <result>
  <fqdn>fqdnB</fqdn>
  <ip_address>ip1</ip_address>
  <u_display_name>display1</u_display_name>
  <name>name1</name>
  <mac_address>mac5</mac_address>
  <u_ci_id>id 1</u_ci_id>
 </result>
 <result>
  <fqdn>fqdnA</fqdn>
  <ip_address>ip2</ip_address>
  <u_display_name>display2</u_display_name>
  <name>name2</name>
  <mac_address>mac4</mac_address>
  <u_ci_id>id 2</u_ci_id>
</result>
</response>

[download]
poj

Replies are listed 'Best First'.
Re^2: Need help with node names for creating header line
by vlturner (Sexton) on Dec 30, 2015 at 18:21 UTC
    I need this: 
    my $input_xml = $client->responseContent();

instead of

my $input_xml = do { local $/; <DATA> };

which breaks at

push @data,[ map { $record->first_child($_)->text } @cols];

Because of the $_

    [download]
[reply]
[d/l]

      Without $_

      for my $record ($root->children) {
  my @tmp=();
  for my $col (@cols){
    push @tmp,$record->first_child($col)->text;
  }
  push @data,[ @tmp ];
}

      [download]
      poj
[reply]
[d/l]

        Are some tags missing ?. If so you will need to decide how to deal with them.

        for my $record ($root->children) {
  my @tmp=();
  for my $col (@cols){
    if (defined $record->first_child($col)){
      push @tmp,$record->first_child($col)->text;
    } else {
      push @tmp,'';;        
    }
  }
  push @data,[ @tmp ];
}

        [download]
        poj
[reply]
[d/l]
        Still getting this error perl CMDB_Sample.pl Can't call method "text" on an undefined value at CMDB_Sample.pl line 62.
[reply]
[reply]
[d/l]
        OK, took out extraneous lines. Still getting following error: perl CMDB_Sample.pl Can't call method "text" on an undefined value at CMDB_Sample.pl line 46. 
        
#!/usr/bin/perl
use strict;
use warnings;
use 5.014;
use MIME::Base64;
use Data::Dumper;
use XML::Twig;
use REST::Client;
# Just in case we want to request JSON instead of XML from CMDB
#use JSON; Just in case we want to request JSON instead of XML from CM
+DB
 
 
 # Set the request parameters
 my $host = 'https://staplessb.service-now.com';
 
 # Eg. User name="admin", Password="admin" for this code sample.
 my $user = 'USERNAME';
 my $pwd = 'PASSWORD';

 my $client = REST::Client->new(host => $host);
 
 my $encoded_auth = encode_base64("$user:$pwd", '');
 
my $header = 'checked_in,change_request,po_number,correlation_id,cfg_a
+uto_provider,supported_by,u_service_catalogtrue,first_discovered,u_oe
+m_part_numbe,sent_for_repair,owned_by,gl_account,managed_by,asset,u_p
+roject_id,maintenance_schedule,u_chgfalse,category,delivery_date,inst
+all_status,u_maintenance_window,virtualfalse,u_sub_class,dns_domain,u
+_incident,u_parts_software_needed,change_control,checked_out,u_decomm
+ission_stamp,purchase_date,order_date,u_template,skip_sync,lease_id,u
+_sevice_options,vendor,sys_id,u_maint_contract_sla,sys_created_by,u_s
+la_support_tie,subcategory,start_date,comments,location,link,value,un
+verified,justification,u_disposal_date,sys_tags,sys_domain,link,value
+,sys_mod_count,cost_cc,u_total_purchase_cost,monitor,sys_updated_on,w
+arranty_expiration,invoice_number,fqdn,cost,u_retail_grp,u_server_typ
+e,ip_address,u_manufacture_date_dummy,last_discovered,model_id,link,v
+alue,manufacturer,u_incfalse,company,due,cfg_auto_management_server,u
+_proposed,u_change,u_work_notes,u_store_location,asset_tag,discovery_
+source,u_application_id,assignment_group,can_print,u_problem,departme
+nt,u_manufacture_date,support_group,link,value,u_exclusion,sys_create
+d_on,u_display_name,u_alias,cost_center,short_description,sys_updated
+_by,name,u_environment,u_function,due_in,u_change_approver,install_da
+te,assigned,u_active_stamp,u_retail_group,serial_number,u_work_notes_
+_asset_,repair_contract_id,assigned_to,mac_address,model_number,sched
+ule,u_ci_id,returned_from_repair,ng_assignment_flag,u_procurement_pro
+duct_number,sys_class_name,attributes,u_location_stamp,fault_count,cf
+g_auto_change';

$client->GET("/api/now/table/cmdb_ci?sysparm_limit=5&sysparm_fields=($
+header)",
                               
                {'Authorization' => "Basic $encoded_auth",
                 
                 'Accept' => 'application/xml'}); 
 
my $field= $ARGV[0] || 'u_ci_id';
my $input_xml = $client->responseContent();

my $twig = new XML::Twig;
$twig->xparse($input_xml);
my $root = $twig->root();

my @data = ();
my @cols = split ',',$header;
unshift @cols, $field; # added for sort

for my $record ($root->children) {
  my @tmp=();
  for my $col (@cols){
    push @tmp,$record->first_child($col)->text;
  }
  push @data,[ @tmp ];
}

my @sorted = sort { $b->[0] cmp $a->[0] } @data;
print $header."\n";
for (@sorted){
  print join ',',@$_[1..$#cols]; # exclude sort col
  print "\n";
}

__DATA__
<?xml version="1.0" encoding="UTF-8"?>
<response>
    <result>
        <checked_in></checked_in>
        <change_request></change_request>
        <po_number></po_number>
        <correlation_id></correlation_id>
        <cfg_auto_provider></cfg_auto_provider>
        <supported_by></supported_by>
        <u_service_catalog>true</u_service_catalog>
        <first_discovered></first_discovered>
        <u_oem_part_numbe></u_oem_part_numbe>
        <sent_for_repair></sent_for_repair>
        <owned_by></owned_by>
        <gl_account></gl_account>
        <managed_by></managed_by>
        <asset></asset>
        <u_project_id></u_project_id>
        <maintenance_schedule></maintenance_schedule>
        <u_chg>false</u_chg>
        <category></category>
        <delivery_date></delivery_date>
        <install_status></install_status>
        <u_maintenance_window></u_maintenance_window>
        <virtual>false</virtual>
        <u_sub_class></u_sub_class>
        <dns_domain></dns_domain>
        <u_incident></u_incident>
        <u_parts_software_needed></u_parts_software_needed>
        <change_control></change_control>
        <checked_out></checked_out>
        <u_decommission_stamp></u_decommission_stamp>
        <purchase_date></purchase_date>
        <order_date></order_date>
        <u_template></u_template>
        <skip_sync></skip_sync>
        <lease_id></lease_id>
        <u_sevice_options></u_sevice_options>
        <vendor></vendor>
        <sys_id></sys_id>
        <u_maint_contract_sla></u_maint_contract_sla>
        <sys_created_by></sys_created_by>
        <u_sla_support_tie></u_sla_support_tie>
        <subcategory></subcategory>
        <start_date></start_date>
        <comments></comments>
        <location>
            <link></link>
            <value></value>
        </location>
        <unverified></unverified>
        <justification></justification>
        <u_disposal_date></u_disposal_date>
        <sys_tags></sys_tags>
        <sys_domain>
            <link></link>
            <value></value>
        </sys_domain>
        <sys_mod_count></sys_mod_count>
        <cost_cc></cost_cc>
        <u_total_purchase_cost></u_total_purchase_cost>
        <monitor></monitor>
        <sys_updated_on></sys_updated_on>
        <warranty_expiration></warranty_expiration>
        <invoice_number></invoice_number>
        <fqdn></fqdn>
        <cost></cost>
        <u_retail_grp></u_retail_grp>
        <u_server_type></u_server_type>
        <ip_address></ip_address>
        <u_manufacture_date_dummy></u_manufacture_date_dummy>
        <last_discovered></last_discovered>
        <model_id>
            <link></link>
            <value></value>
        </model_id>
        <manufacturer></manufacturer>
        <u_inc>false</u_inc>
        <company></company>
        <due></due>
        <cfg_auto_management_server></cfg_auto_management_server>
        <u_proposed></u_proposed>
        <u_change></u_change>
        <u_work_notes></u_work_notes>
        <u_store_location></u_store_location>
        <asset_tag></asset_tag>
        <discovery_source></discovery_source>
        <u_application_id></u_application_id>
        <assignment_group></assignment_group>
        <can_print></can_print>
        <u_problem></u_problem>
        <department></department>
        <u_manufacture_date></u_manufacture_date>
        <support_group>
            <link></link>
            <value></value>
        </support_group>
        <u_exclusion></u_exclusion>
        <sys_created_on></sys_created_on>
        <u_display_name></u_display_name>
        <u_alias></u_alias>
        <cost_center></cost_center>
        <short_description></short_description>
        <sys_updated_by></sys_updated_by>
        <name></name>
        <u_environment></u_environment>
        <u_function></u_function>
        <due_in></due_in>
        <u_change_approver></u_change_approver>
        <install_date></install_date>
        <assigned></assigned>
        <u_active_stamp></u_active_stamp>
        <u_retail_group></u_retail_group>
        <serial_number></serial_number>
        <u_work_notes__asset_></u_work_notes__asset_>
        <repair_contract_id></repair_contract_id>
        <assigned_to></assigned_to>
        <mac_address></mac_address>
        <model_number></model_number>
        <schedule></schedule>
        <u_ci_id></u_ci_id>
        <returned_from_repair></returned_from_repair>
        <ng_assignment_flag></ng_assignment_flag>
        <u_procurement_product_number></u_procurement_product_number>
        <sys_class_name></sys_class_name>
        <attributes></attributes>
        <u_location_stamp></u_location_stamp>
        <fault_count></fault_count>
        <cfg_auto_change></cfg_auto_change>
    </result>
</response>';

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[d/l]

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