I written one script that create one xml file from multiple files,I written script like this.
#!/usr/bin/perl
use warnings;
use strict;
use XML::LibXML;
use Carp;
use File::Find;
use File::Spec::Functions qw( canonpath );
use XML::LibXML::Reader;
use Digest::MD5 'md5';
if ( #ARGV == 0 ) {
push #ARGV, "c:/main/work";
warn "Using default path $ARGV[0]\n Usage: $0 path ...\n";
}
open( my $allxml, '>', "all_xml_contents.combined.xml" )
or die "can't open output xml file for writing: $!\n";
print $allxml '<?xml version="1.0" encoding="UTF-8"?>',
"\n<Shiporder xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\">\n";
my %shipto_md5;
find(
sub {
return unless ( /(_stc\.xml)$/ and -f );
extract_information();
return;
},
#ARGV
);
print $allxml "</Shiporder>\n";
sub extract_information {
my $path = $_;
if ( my $reader = XML::LibXML::Reader->new( location => $path )) {
while ( $reader->nextElement( 'data' )) {
my $elem = $reader->readOuterXml();
my $md5 = md5( $elem );
print $allxml $reader->readOuterXml() unless ( $shipto_md5{$md5}++ );
}
}
return;
}
from above script I am extracting data node information from all xml files and stored in a new xml file . but I have one more node starts with "details", I need to extract that information and I need to add that information also to the file, I tried like this
$reader->nextElement( 'details' );
my $information = $reader->readOuterXml();
I added this in while loop but how can I assign or print this data into same file($all xml). Please help me with this problem.
After your suggestion I tried like this, It gives error
#!/usr/bin/perl
use warnings;
use strict;
use XML::LibXML;
use Carp;
use File::Find;
use File::Spec::Functions qw( canonpath );
use XML::LibXML::Reader;
if ( #ARGV == 0 ) {
push #ARGV, "V:/main/work";
warn "Using default path $ARGV[0]\n Usage: $0 path ...\n";
}
my $libXML = new XML::LibXML;
my $outputDom = $libXML->parse_string('<?xml version="1.0" encoding="UTF-8"?
>','<Shiporder xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">');
my $shiporder = $outputDom->documentElement;
find(
sub {
return unless ( /(_stc\.xml)$/ and -f );
extract_information();
return;
},
#ARGV
);
sub extract_information {
my $path = $_;
if(my #inputDom = XML::LibXML->load_xml(location => $path)){
$inputDom->findnodes('//data || //deatils');
foreach (#$inputDom) {
$shiporder->appendChild($_->parentNode->cloneNode(1));
}
$outputDom->toFile("allfiles.xml");
}
}
but it gives like " '\n\n:1: Parser error:Strat tag expected,'<' not found " Can you help me with script because I am very new to perl.
You would do a lot better if you used what XML::LibXML and related modules gives you, it is a very large and comprehensive module and allows you to do a lot in few lines.
You can use the parser to start a new dom document using parse_string, storing the root node using documentElement. From there, use parse_file to load up each of your input files, then findnodes on the input files to extract the nodes you want to clone. Then append a clone of your input nodes to the output document, and finally use the toFile method to write out your output.
Something like:
my $libXML = new XML::LibXML;
my $outputDom = $libXML->parse_string('<?xml version="1.0" encoding="UTF-8"?>',
'\n<Shiporder xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">\n');
my $shiporder = $outputDom->documentElement;
...
my $inputDom = $libXML->parse_file(some_file_name);
$inputDom->findnodes('//data || //details'); # use a more suitable xpath
foreach (#$inputDom) {
$shipOrder->appendChild($_->parentNode->cloneNode(1)); # if you want parent too...
}
...
$outputDom->toFile(some_output_file);
}
You will have to allow for namespaces and whatnot, but this gives one approach to start with.
Related
I'm writing a tool that must import a number of other perl config files. The files are not wrapped w/packages and may have similar or conflicting variables/functions. I don't have the ability to change the format of these files, so I must work around what they are. What I was thinking to do was import each into a unique name space, but I've not found a way to do that using do, require, or use. If I don't use dynamic names, just a hardcoded name, I can do it.
Want something like this:
sub sourceTheFile {
my ($namespace, $file) = #_;
package $namespace;
do $file;
1;
return;
}
That doesn't work because the package command requires a constant for the name. So then I try something like this:
sub sourceTheFile {
my ($namespace, $file) = #_;
eval "package $namespace;do $file;1;"
return;
}
But the contents of the file read by do are placed in the main:: scope not the one I want. The target scope is created, just not populated by the
do. (I tried require, and just a straight cat $file inside the eval as well.)
I'm using Devel::Symdump to verify that the namespaces are built correctly or not.
example input file:
my $xyz = "some var";
%all_have_this = ( common=>"stuff" );
ADDITIONAL CHALLENGE
Using the answer that does the temp file build and do call, I can make this work dynamically as I require. BUT, big but, how do I now reference the data inside this new namespace? Perl doesn't seem to have the lose ability to build a variable name from a string and use that as the variable.
I am not sure why the eval did not work. Maybe a bug? Here is a workaround using a temp file. This works for me:
use strict;
use warnings;
use Devel::Symdump;
use File::Temp;
my $file = './test.pl';
my $namespace = 'TEST';
{
my $fh = File::Temp->new();
print $fh "package $namespace;\n";
print $fh "do '$file';\n";
print $fh "1;\n";
close $fh;
do $fh->filename;
}
Perl's use and require facilities make use of any hooks you might have installed in #INC. You can simply install a hook which looks in a specific location to load modules with a prefix you choose:
package MyIncHook;
use strict;
use warnings;
use autouse Carp => qw( croak );
use File::Spec::Functions qw( catfile );
sub import {
my ($class, $prefix, $location) = #_;
unshift #INC, _loader_for($prefix, $location);
return;
}
sub _loader_for {
my $prefix = shift;
my $location = shift;
$prefix =~ s{::}{/}g;
return sub {
my $self = shift;
my $wanted = shift;
return unless $wanted =~ /^\Q$prefix/;
my $path = catfile($location, $wanted);
my ($is_done);
open my $fh, '<', $path
or croak "Failed to open '$path' for reading: $!";
my $loader = sub {
if ($is_done) {
close $fh
or croak "Failed to close '$path': $!";
return 0;
}
if (defined (my $line = <$fh>)) {
$_ = $line;
return 1;
}
else {
$_ = "1\n";
$is_done = 1;
return 1;
}
};
(my $package = $wanted) =~ s{/}{::}g;
$package =~ s/[.]pm\z//;
my #ret = (\"package $package;", $loader);
return #ret;
}
}
__PACKAGE__;
__END__
Obviously, modify the construction of $path according to your requirements.
You can use it like this:
#!/usr/bin/env perl
use strict;
use warnings;
use MyIncHook ('My::Namespace', "$ENV{TEMP}/1");
use My::Namespace::Rand;
print $My::Namespace::Rand::settings{WARNING_LEVEL}, "\n";
where $ENV{TEMP}/1/My/Namespace/Rand.pm contains:
%settings = (
WARNING_LEVEL => 'critical',
);
Output:
C:\Temp> perl t.pl
critical
You can, obviously, define your own mapping from made up module names to file names.
I want to make a configuration file which hold some objects, like this (where of course none of the paramaters can be considered as a primary key)
param1=abc
param2=ghj
param1=bcd
param2=hjk
; always the sames parameters
This file could be read, lets say with Config::IniFiles, because it has a direct transcription into ini file, like this
[0]
param1=abc
param2=ghj
[1]
param1=bcd
param2=hjk
with, for example, something like
perl -pe 'if (m/^\s*$/ || !$section ) print "[", ($section++ || 0) , "]"'
And finish with
open my $fh, '<', "/path/to/config_file.ini" or die $!;
$cfg = Config::IniFiles->new( -file => $fh );
(...parse here the sections starting with 0.)
But, I here ask me some question about the thing becoming quite complex....
(A) Is There a way to transform the $fh, so that it is not required to execute the perl one-liner BEFORE reading the file sequentially? So, to transform the file during perl is actually reading it.
or
(B) Is there a module to read my wonderfull flat database? Or something approching? I let myslef said, that Gnu coreutils does this kind of flat file reading, but I cannot remember how.
You can create a simple subclass of Config::INI::Reader:
package MyReader;
use strict;
use warnings;
use base 'Config::INI::Reader';
sub new {
my $class = shift;
my $self = $class->SUPER::new( #_ );
$self->{section} = 0;
return $self;
}
sub starting_section { 0 };
sub can_ignore { 0 };
sub parse_section_header {
my ( $self, $line ) = #_;
return $line =~ /^\s*$/ ? ++$self->{section} : undef ;
}
1;
With your input this gives:
% perl -MMyReader -MData::Dumper -e 'print Dumper( MyReader->read_file("cfg") )'
$VAR1 = {
'1' => {
'param2' => 'hjk',
'param1' => 'bcd'
},
'0' => {
'param2' => 'ghj',
'param1' => 'abc'
}
};
You can use a variable reference instead of a file name to create a filehandle that reads from it:
use strict;
use warnings;
use autodie;
my $config = "/path/to/config_file.ini";
my $content = do {
local $/;
open my $fh, "<", $config;
"\n". <$fh>;
};
# one liner replacement
my $section = 0;
$content =~ s/^\s*$/ "\n[". $section++ ."]" /mge;
open my $fh, '<', \$content;
my $cfg = Config::IniFiles->new( -file => $fh );
# ...
You can store the modified data in a real file or a string variable, but I suggest that you use paragraph mode by setting the input record separator $/ to the empty string. Like this
use strict;
use warnings;
{
local $/ = ''; # Read file in "paragraphs"
my $section = 0;
while (<DATA>) {
printf "[%d]\n", $section++;
print;
}
}
__DATA__
param1=abc
param2=ghj
param1=bcd
param2=hjk
output
[0]
param1=abc
param2=ghj
[1]
param1=bcd
param2=hjk
Update
If you read the file into a string, adding section identifiers as above, then you can read the result directly into a Config::IniFiles object using a string reference, for instance
my $config = Config::IniFiles->new(-file => \$modified_contents)
This example shows the tie interface, which results in a Perl hash that contains the configuration information. I have used Data::Dump only to show the structure of the resultant hash.
use strict;
use warnings;
use Config::IniFiles;
my $config;
{
open my $fh, '<', 'config_file.ini' or die "Couldn't open config file: $!";
my $section = 0;
local $/ = '';
while (<$fh>) {
$config .= sprintf "[%d]\n", $section++;
$config .= $_;
}
};
tie my %config, 'Config::IniFiles', -file => \$config;
use Data::Dump;
dd \%config;
output
{
# tied Config::IniFiles
"0" => {
# tied Config::IniFiles::_section
param1 => "abc",
param2 => "ghj",
},
"1" => {
# tied Config::IniFiles::_section
param1 => "bcd",
param2 => "hjk",
},
}
You may want to perform operations on a flux of objects (as Powershell) instead of a flux of text, so
use strict;
use warnings;
use English;
sub operation {
# do something with objects
...
}
{
local $INPUT_RECORD_SEPARATOR = '';
# object are separated with empty lines
while (<STDIN>) {
# key value
my %object = ( m/^ ([^=]+) = ([[:print:]]*) $ /xmsg );
# key cannot have = included, which is the delimiter
# value are printable characters (one line only)
operation ( \%object )
}
A like also other answers.
I am new to perl scripting. I am trying to get the count of directories & subdirectories.
So I have searched all the available help on scripting.
But unable get the count of Subdirectories. Below is the script I used.
use strict;
use warnings;
use File::Slurp;
my #dirs = ('.');
my $directory_count = 0;
my $file_count = 0;
my $outfile = 'log.txt';
open my $fh, '>', $outfile or die "can't create logfile; $!";
for my $dir (#dirs) {
for my $file (read_dir ($dir)) {
if ( -d "$dir/$file" ) {
$directory_count++;
}
else {
$file_count++;
}
}
print $fh "Directories: $directory_count\n";
print $fh "Files: $file_count\n";
}
close $fh;
Here, I am unable to identify where to change the command of dir with /s.
Please help it will reduce lot of manual work.
Ravi
Never EVER write your own directory traversal. There are too many pitfalls, gotchas and edge cases. Things like path delimiters, files with spaces, alternate data streams, soft links, hard links, DFS paths... just don't do it.
Use File::Find or if you prefer File::Find::Rule.
As I prefer the former, I'll give an example:
use strict;
use warnings;
use File::Find;
my $dir_count;
my $file_count;
#find runs this for every file in it's traversal.
#$_ is 'current file'. $File::Find::Name is full path to file.
sub count_stuff {
if ( -d ) { $dir_count++ };
if ( -f ) { $file_count++ };
}
find ( \&count_stuff, "." );
print "Dirs: $dir_count\n";
print "Files: $file_count\n";
Here is a script that does it: 1) without global variables; and 2) without adding another sub to the namespace.
#!/usr/bin/env perl
use strict;
use warnings;
use File::Find;
run(\#ARGV);
sub run {
my $argv = shift;
for my $dir ( #$argv ) {
my $ret = count_files_and_directories( $dir );
printf(
"%s: %d files and %d directories\n",
$dir,
$ret->{files},
$ret->{directories}
);
}
return;
}
sub count_files_and_directories {
my $top = shift;
my %ret = (directories => 0, files => 0);
find(
{
wanted => sub {
-d and $ret{directories} += 1;
-f and $ret{files} += 1;
},
no_chdir => 1,
},
$top,
);
\%ret;
}
It seems simpler to use File::Find::Rule.. For example:
use warnings;
use strict;
use File::Find::Rule;
my #files = File::Find::Rule->new->file->in('.');
my #dirs = File::Find::Rule->new->directory->in('.');
I am unable to print the whole lines as i try and parse the ini file using Config:Ini operation, its the last part where I believed that the array will have the whole line and not only the key, I am surely missing something here
Input
[DomainCredentials]
broker=SERVER
domain=CUSTOMER1
[ProviderCredentials]
Class=A
Routine=B
Code
#!/sbin/perl -w
use lib "/usr/lib/perl5/site_perl";
use lib "/usr/lib/perl5/vendor_perl";
use strict;
use warnings;
use Config::IniFiles;
my $sPPFile="/tmp/config.txt";
my $sysSec="DomainCredentials";
my $cfg = Config::IniFiles->new(-file=> $sPPFile) || die "Could open file $sPPFile\n";
if ($#){
print "Error";
exit 1;
}
my #params_provider = $cfg->Parameters("ProviderCredentials");
foreach (#params_provider){
print $_."\n";
}
Output
Class
Routine
Expected Output
Class=A
Routine=B
You could use the tied hash option of Config::IniFiles to get the config.txt parameter/value pairs:
use strict;
use warnings;
use Config::IniFiles;
my %ini;
my $sPPFile = "/tmp/config.txt";
tie %ini, 'Config::IniFiles', ( -file => $sPPFile );
print "$_=$ini{ProviderCredentials}{$_}\n"
for keys %{ $ini{ProviderCredentials} };
Output on your dataset:
Class=A
Routine=B
You can change the value of a parameter, and then update the config file by doing this:
$ini{ProviderCredentials}{Class} = 'C';
tied(%ini)->RewriteConfig();
The last command actually writes out the entire config held in the tied hash.
Hope this helps!
It looks like Parameters only returns keys.
You then have to use val to get the values.
#!/sbin/perl -w
use lib "/usr/lib/perl5/site_perl";
use lib "/usr/lib/perl5/vendor_perl";
use strict;
use warnings;
use Config::IniFiles;
my $sPPFile="/tmp/config.txt";
my $sysSec="DomainCredentials";
my $cfg = Config::IniFiles->new(-file=> $sPPFile) || die "Could open file $sPPFile\n";
if ($#){
print "Error";
exit 1;
}
my #param_arr = ('broker','domain');
my %param_hash;
foreach my $p (#param_arr){
if (defined $cfg->val("$sysSec",$p)){
$param_hash{$p} = $cfg->val("$sysSec",$p);
}
else{
die "Could not get parameter $p\n";
}
}
#print $param_hash{broker};
#print $param_hash{domain};
my #params_provider = $cfg->Parameters("ProviderCredentials");
if (defined $cfg->Parameters("ProviderCredentials")){
my #params_provider = $cfg->Parameters("ProviderCredentials");
}else{
die "Could not get parameter ProviderCredentials\n";
}
foreach (#params_provider){
print "Key : ".$_."\t Value : ".$cfg->val("ProviderCredentials",$_)."\n";
}
I have Perl and CSV file with something like:
"Name","Lastname"
"Homer","Simpsons"
"Ned","Flanders"
In this CSV file I have header in the first line and in other lines there are
data.
I want to convert this CSV file to such Perl data:
[
{
Lastname => "Simpsons",
Name => "Homer",
},
{
Lastname => "Flanders",
Name => "Ned",
},
]
I've written the function that users Text::CSV and doing what I need.
Here is the sample script:
#!/usr/bin/perl
use strict;
use warnings FATAL => 'all';
use 5.010;
use utf8;
use open qw(:std :utf8);
use Text::CSV;
sub read_csv {
my ($filename) = #_;
my #first_line;
my $result;
my $csv = Text::CSV->new ({ binary => 1, auto_diag => 1 });
open my $fh, "<:encoding(utf8)", $filename or die "$filename: $!";
while (my $row = $csv->getline ($fh)) {
if (not #first_line) {
#first_line = #{$row};
} else {
push #{$result}, { map { $first_line[$_] => $row->[$_] } 0..$#first_line };
}
}
close $fh;
return $result;
}
my $data = read_csv('sample.csv');
This works fine but this function I want to use in several scripts. I'm
greatly suprised that Text::CSV doesn't have this feature.
My question. What should I do to simplify solving such tasks in the future for
me and others?
Should I use some Perl module from CPAN, should I try to add this function to
Text::CSV, or something else?
Huh? Why so complicated? First, we fetch the header outside of the loop:
my $headers = $csv->getline($fh) or die "no header";
Assign these to be the column names:
$csv->column_names(#$headers);
Then, each call to getline_hr will provide a hashref:
while (my $hashref = $csv->getline_hr($fh)) {
push #$result, $hashref;
}
We can also use getline_hr_all:
$result = $csv->getline_hr_all($fh);
In other words, it ain't complex, most pieces are already provided by Text::CSV, and it can be done in very few lines.
Also, a module like this seems to already exist: Text::CSV::Slurp. (note: reverse dependency search through metacpan is awesome)
It's probably not a standard feature because different people will want their CSV files parsed into different data structures.
Why not create your own module that wraps this function?
package CSVRead;
use strict;
use warnings;
use 5.010;
use open qw(:std :utf8);
use Text::CSV;
require Exporter;
our #ISA = qw(Exporter);
our #EXPORT = qw(read_csv);
sub read_csv {
my ($filename) = #_;
my #first_line;
my $result;
my $csv = Text::CSV->new ({ binary => 1, auto_diag => 1 });
open my $fh, "<:encoding(utf8)", $filename or die "$filename: $!";
while (my $row = $csv->getline ($fh)) {
if (not #first_line) {
#first_line = #{$row};
} else {
push #{$result}, { map { $first_line[$_] => $row->[$_] } 0..$#first_line };
}
}
close $fh;
return $result;
}
Then, use it like this:
#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
use Data::Dumper;
use CSVRead;
my $data = read_csv('sample.csv');
say Dumper $data;