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Browse CPAN modules per namespaces

thibaultduponchelle

Tib

Posted on February 22, 2021

Browse CPAN modules per namespaces

I once was looking to filter out CPAN modules per namespace. Namespaces generally have meaning in CPAN since there are conventions and Perl folks try to be rigourous and to fit well in the existing naming

So back again to my research, I was looking for a way to filter out CPAN modules per namespaces.

Become the master of MetaCPAN search

From METACPAN faq you can get some tips like the module: prefix
MetaCPAN tips

With this trick, you can search for instance all XML related modules

It works well, but does not achieve exactly what I want since it returns me also for instance the SVG::XML which is not actually prefixed by XML::
Problem

CPANMeta the great

By asking on the good old IRC, I get a solution thanks to CPANMeta

You can then list all XML::* modules
CPANMeta

Manual grep

The quick and dirty hack!

I downloaded the 02packages.details.txt file from CPAN.org

Then using a grep

grep "^XML::" 02packages.details.txt
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And the output is a long list of modules:

XML::XSS                         v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::Comment                v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::Document               v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::Element                v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::ProcessingInstruction  v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::Role::Renderer         v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::Role::StyleAttribute   v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::StyleAttribute         v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::Stylesheet::HTML2TD    v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::Template               v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XSS::Text                   v0.3.5  Y/YA/YANICK/XML-XSS-0.3.5.tar.gz
XML::XUpdate::LibXML           0.006000  P/PA/PAJAS/XML-XUpdate-LibXML-0.6.0.tar.gz
XML::YYLex                         0.04  B/BO/BOEWE/XML-YYLex-0.04.tar.gz
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More experiments

I tried also to use CPAN::02Packages::Search but it seems to only allow exact match.

Look at this working code

#!/usr/bin/env perl

use CPAN::02Packages::Search;
use Data::Dumper;

my $index = CPAN::02Packages::Search->new(file => './02packages.details.txt');
my $res = $index->search('Plack'); 

print Dumper($res);
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I tried to tweak it with $index->search('XML::*'); or $index->search('XML::.*'); but it is not valid 😕

CPAN::Common::Index::Mirror is promising to do the job according to the documentation
Index

But I was not able to make it work at first 😃

I started with this code snippet

#!/usr/bin/env perl

use CPAN::Common::Index::Mux::Ordered;
use Data::Dumper;

my $index = CPAN::Common::Index::Mux::Ordered->assemble(
    MetaDB => {},
    Mirror => { mirror => "http://cpan.cpantesters.org" },
);

my $result = $index->search_packages( { package => 'XML::LibXML' } );

print Dumper($result);
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And tried various XML::* and XML::.* and /^XML::.*/ and m/^XML::.*/ and the same with - instead of :: but no way 😬

Thanks to @grinnz , I get it!

#!/usr/bin/env perl

use CPAN::Common::Index::Mux::Ordered;
use Data::Dumper;

my $index = CPAN::Common::Index::Mux::Ordered->assemble(
    MetaDB => {},
    Mirror => { mirror => "http://cpan.cpantesters.org" },
);

my @result = $index->search_packages( { package => qr/^XML::/ });

print Dumper(@result);
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That will returns several packages:

$VAR2326 = {
             'version' => 'undef',
             'package' => 'XML::XSH::Parser',
             'uri' => 'cpan:///distfile/CHOROBA/XML-XSH-1.8.6.tar.gz'
           };
$VAR2327 = {
             'version' => '0.48',
             'package' => 'XML::XSLT',
             'uri' => 'cpan:///distfile/JSTOWE/XML-XSLT-0.48.tar.gz'
           };
$VAR2328 = {
             'package' => 'XML::XSLT::DOM::TextDOE',
             'version' => '0.31',
             'uri' => 'cpan:///distfile/MAHEX/XML-XSLT-0.31.tar.gz'
           };
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I see there are also some other possible alternatives like App::CPANIDX or maybe CPANDB?

MetaCPAN native treeview

I wonder if it should not simply be part of MetaCPAN. I other words a native tree view in MetaCPAN 💃

Maybe I'm missing a point, but a feature like this would make me happy for a while.

What about something like
CPAN treeview

What do you think?

💖 💪 🙅 🚩
thibaultduponchelle
Tib

Posted on February 22, 2021

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February 22, 2021