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NAME

Tree::Navigator - Generic navigation in various kinds of trees

SYNOPSIS

Create a file treenav.psgi like this :

  # create a navigator, then mount various kinds of nodes as shown below
  use Tree::Navigator;
  my $tn = Tree::Navigator->new;

  # example 1 : browse through the filesystem
  $tn->mount(Files => Filesys 
                   => {attributes => {label => 'My Web Files'},
                       mount_point => {root  => '/path/to/files'}});

  # example 2 : inspect tables and columns in a database
  my $dbh = DBI->connect(...);
  $tn->mount(MyDB => 'DBI' => {mount_point => {dbh => $dbh}});

  # example 3 : browse through the Win32 registry
  $tn->mount(HKCU => 'Win32::Registry' => {mount_point => {key => 'HKCU'}});

  # example 4 : browse through Perl internals
  $tn->mount(Ref => 'Perl::Ref' => {mount_point => {ref => $some_ref}});
  $tn->mount(Stack => 'Perl::StackTrace' => {mount_point => {}});
  $tn->mount(Symdump => 'Perl::Symdump' => {});

  # create the application
  my $app = $tn->to_app;

Then run the app

  plackup treenav.psgi

or mount the app in Apache

  <Location /treenav>
    SetHandler perl-script
    PerlResponseHandler Plack::Handler::Apache2
    PerlSetVar psgi_app /path/to/treenav.psgi
  </Location>

and use your favorite web browser to navigate through your data.

DESCRIPTION

Introduction

This is a set of tools for navigating within various kinds of trees; a tree is just a set of nodes, where each node may have a content, may have attributes, and may have children nodes. Examples of such structures are filesystems, FTP sites, email boxes, Web sites, HTML pages, XML documents, etc.

The distribution provides

  • an abstract class for nodes, with a few concrete classes for some of the examples just mentioned above

  • a server application for exposing the tree structure to web clients

  • a debugging application that uses the Tree Navigator to navigate into the memory of a running Perl program.

Status

This application was built as a proof-of-concept in 2012 and hasn't been much reworked since. It is functional and actually is being used in production for some minor tasks, but is not polished into a fully documented product. A minor modernization was performed in 2024 to remove deprecated features no longer supported by recent versions of perl.

Implemented nodes

The following kinds of nodes come with the distribution and therefore can readily be mounted into a tree navigator :

Tree::Navigator::Node::DBI

Displays the metadata (tables and columns) of a database. Navigation within the data rows is not implemented yet.

Tree::Navigator::Node::DBIDM

Meant to navigate in a database through a DBIx::DataModel schema. Not fully implemented.

Tree::Navigator::Node::Filesys

Navigation in a filesystem, displaying file attributes and providing a download facility.

Tree::Navigator::Node::Perl::Ref

Navigation in a perl datastructure.

Tree::Navigator::Node::Perl::StackTrace

Navigation in a perl stacktrace.

Tree::Navigator::Node::Perl::Symdump

Navigation in a perl symbol table.

Tree::Navigator::Node::Win32::Registry

Navigation in Windows registry.

Other kinds of nodes can be integrated into the framework by subclassing Tree::Navigator::Node with methods for accessing the node's content, attributes and children.

METHODS

call

Main request dispatcher (see "Component" in Plack).

DEPENDENCIES

This application uses Plack and Moose.

AUTHOR

Laurent Dami, <dami at cpan.org>

SEE ALSO

Tree::Simple

LICENSE AND COPYRIGHT

Copyright 2012, 2024 Laurent Dami.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.