=head1 NAME

Unix::Mgt - lightweight Unix management tools

=head1 SYNOPSIS

 # get user account
 $user = Unix::Mgt::User->get('fred');

 # display some info
 print 'uid: ', $user->uid, "\n";
 print join(', ', $user->groups()), "\n";

 # set some properties
 $user->gid('websters');
 $user->shell('/bin/bash');
 $user->add_to_group('postgres');

 # create user account
 $user = Unix::Mgt::User->create('vera');

 # get user account, creating it if necessary
 $user = Unix::Mgt::User->ensure('molly');

 # get group
 $group = Unix::Mgt::Group->get('www-data');

 # display some info
 print 'gid: ', $group->gid, "\n";
 print join(', ', $group->members()), "\n";

 # add a member
 $group->add_member('tucker');

=head1 DESCRIPTION

Unix::Mgt provides simple object-oriented tools for managing your Unixish
system.  Currently this module provides tools for managing users and groups.
Other tools may follow as they evolve.

Unix::Mgt does not directly manipulate any of the system files such as
C</etc/passwd>. This module uses Perl's built-in Unix functions such as
C<getgrent> to get information, and Unix's built-in programs such as
C<adduser>.

=head2 Early release

In the spirit of "release early, release often", I'm releasing this version
of Unix::Mgt before it has all the features that might be expected. This
version does not include methods for removing users from groups, renaming
users or groups, or several other methods.

=head2 Help with BSD development

This version does not work well on BSDish systems. Although the methods for
retrieving information such as C<get> and C<group> work well, this module
currently cannot create, modify, or delete users or group. If you'd like to
help fill in these features, here's what needs to be done.

Several places in the code is the comment "BSD code needed". In those places
what we need is to build an array consisting of an external command and the
arguments to be sent to the command. It would look something like this:

 # build command
 @cmd = (
    'pw', 
    'useradd', 
    $user->{'name'},
    '-G', 
    $group->{'name'},
 );

The first element of the array is the program to be run. You don't need to put
the full path of the program, L<Unix::SearchPathGuess> should find it. (If it
doesn't please let me know, we may need to fix Unix::SearchPathGuess.) The
remaining elements are the params sent to the program using
L<IPC::System::Simple>. The program is not run in a shell, but instead is
called directly, so it isn't necessary to do any shell escaping.

The following methods currently need patching. In Unix::Mgt::User we need
create(), field_get_set(), group(), add_to_group(), and remove(). In
Unix::Mgt::Group we need create() and remove(). We will need more as we add
features to this module.

Please email me at miko@idocs.com if you've made these mods.

=head1 Unix::Mgt::User

A Unix::Mgt::User object represents a user in the Unix system. The object
allows you to get and set information about the user account. A user object
is created in one of three ways: C<get>, C<create>, or C<ensure>. Note that
there is no C<new> method.

Unix::Mgt::User objects stringify to the account's name. For example, the
following code would output C<miko>.

 $user = Unix::Mgt::User->get('miko');
 print $user, "\n";

=head2 get

Unix::Mgt::User->get() retrieves user account information using C<getpwnam> or
C<getpwuid>.  The single param for this method is either the name or the uid of
the user.

 $user = Unix::Mgt::User->get('vera');
 $user = Unix::Mgt::User->get('1010');

If the user is not found then the C<do-not-have-user> error id is set in
C<$Unix::Mgt::err_id> and undef is returned.

=head2 create

Unix::Mgt::User->create() creates a user account.  The required param for this
method is the name for the new account.

 $user = Unix::Mgt::User->create('vera');

If the C<system> param is true, then the account is created as a system user,
like this:

 $user = Unix::Mgt::User->create('lanny', system=>1);

create() uses the Unix C<adduser> program.

=head2 ensure

Unix::Mgt::User->ensure() gets a user account if it already exists, and
creates the account if it does not. For example, the following lines ensures
the C<molly> account:

 $user = Unix::Mgt::User->ensure('molly');

=head2 name

Returns the name of the user account. Currently this method cannot be used to
set the account name.

 print $user->name(), "\n";

=head2 uid

Returns the user's user id (uid).

 print $user->uid(), "\n";

=head2 passwd

Returns the password field from C<getpwname()>.  This method will not actually
return a password, it will probably just return C<*>.

 print $user->passwd(), "\n"; # probably outputs "*"

=head2 gid

Sets/gets the gid of the user's primary group. Called without params, it
returns the user's gid:

 print $user->gid(), "\n";

Called with a single param, gid() sets, then returns the user's primary
group id:

 print $user->gid('1010'), "\n";

If you want to get a Unix::Mgt::Group object representing the user's primary
group, use $user->group().

=head2 dir

Sets/gets the user's home directory. Called without params, it returns the
directory name:

 print $user->dir(), "\n";

Called with a single param, dir() sets, then returns the user's home directory:

 print $user->dir('/tmp'), "\n";

=head2 shell

Sets/gets the user's default command line shell. Called without params, it
returns the shell name:

 print $user->shell(), "\n";

Called with a single param, shell() sets, then returns the user's shell:

 print $user->shell('/bin/sh'), "\n";

=head2 group

Sets/gets the user's primary group. When called without any params, C<group()>
returns a Unix::Mgt::Group object representing the user's primary group:

 $group = $user->group();

When called with a single param, C<group()> sets the user's primary group. The
param can be either the group's name or its gid:

 $user->group('video');
 $user->group(44);

=head2 secondary_groups

C<secondary_groups()> returns an array of the user's secondary groups. Each
element in the array is a Unix::Mgt::Group object.

 @groups = $user->secondary_groups();

=head2 groups

C<groups()> returns an array of all of the groups the user is a member of. The
first element in the array will be the user's primary group.

 @groups = $user->groups();

=head2 add_to_group

C<add_to_group()> adds the user to a group.  The group will be one of the user's
secondary groups, not the primary group.

 $user->add_to_group('video');

=head2 remove

C<remove> removes the user account from the system. C<remove> does not take any
parameters.

 $user->remove();

=head1 Unix::Mgt::Group

A Unix::Mgt::Group object represents a group in the Unix system. The object
allows you to get and set information about the group. A group object is
created in one of three ways: C<get>, C<create>, or C<ensure>. Note that
there is no C<new> method.

Unix::Mgt::Group objects stringify to the groups's name. For example, the
following code would output C<video>.

 $group = Unix::Mgt::Group->get('video');
 print $group, "\n";

=head2 get

Unix::Mgt::Group->get() retrieves group information using C<getgrnam> or
C<getgrgid>.  The single param for this method is either the name or the gid of
the group.

 $group = Unix::Mgt::Group->get('video');
 $group = Unix::Mgt::Group->get('44');

If the group is not found then the C<do-not-have-group> error id is set in
C<$Unix::Mgt::err_id> and undef is returned.

=head2 create

Unix::Mgt::Group->create() creates a group.  The required param for this method
is the name for the new group.

 $group = Unix::Mgt::Group->create('websters');

create() uses the Unix C<groupadd> program.

=head2 ensure

Unix::Mgt::Group->ensure() gets a group if it already exists, and creates the
group if it does not. For example, the following lines ensures
the C<wbesters> group:

 $group = Unix::Mgt::User->ensure('wbesters');

=head2 name

Returns the name of the group. Currently this method cannot be used to set the
group name.

 print $group->name(), "\n";

=head2 gid

Returns the groups's group id (gid).

 print $group->gid(), "\n";

=head2 members

C<members()> returns an array of all members of the group. Both users for whom
this is the primary group, and users for whom this is a secondary group are
returned.

 @members = $group->members();

The elements in the array are Unix::Mgt::User objects.

=head2 primary_members

C<primary_members()> returns an array of users for whom this is the primary
group.

 @members = $group->primary_members();

The elements in the returned array are Unix::Mgt::User objects.

=head2 secondary_members

C<secondary_members()> returns an array of users for whom this is a secondary group.

 @members = $group->secondary_members();

The elements in the returned array are Unix::Mgt::User objects.

=head2 add_member

C<add_member()> adds a user to the group as a secondary group.  The single
param can be a user name, uid, or Unix::Mgt::User object.

 $group->add_member('miko');

If the user is already a member of the group then nothing is done and no error
is set.

=head2 remove

C<remove> removes the group from the system. C<remove> does not take any
parameters.

 $group->remove();

If any users have the group as a primary group then this method will fail.

=head1 SEE ALSO

L<Passwd::Unix|http://search.cpan.org/~strzelec/Passwd-Unix/> and
L<Unix::Passwd::File|http://search.cpan.org/~sharyanto/Unix-Passwd-File/>
provide similar functionality.

=head1 TERMS AND CONDITIONS

Copyright (c) 2014 by Miko O'Sullivan. All rights reserved. This program is
free software; you can redistribute it and/or modify it under the same terms
as Perl itself. This software comes with no warranty of any kind.

=head1 AUTHOR

Miko O'Sullivan C<miko@idocs.com>

=head1 TO DO

This is an early release of Unix::Mgt. It does not include methods for
deleting users, removing them from groups, or other deletion oriented
objectives.

Please feel free to contribute code for these purposes.

=head1 HISTORY

=over 4

=item Version 0.10 December 30, 2014

Initial release

=item Version 0.11 December 31, 2014

Changed addgroup to groupadd.

Added tests for existence of adduser, usermod, and groupadd.

=item Version 0.12 January 3, 2015

Fixed some POD formatting issues.

Revised tests to include test names.

=item Version 0.13 January 4, 2015

Added $user->remove() and $group->remove().

Added slots where BSD-style commands will go. Currently, methods for creating,
modifying, or deleting users or group will fail on BSD.

=back

