SuikaWiki/DB/Logical.pm


=head1 NAME

SuikaWiki::DB::Logical --- SuikaWiki WikiDatabase: Logical database consists of multiple datasources

=head1 DESCRIPTION

This module provides a logical database implementation.  It does not itself have
physical datasource at all.  With database property name asspcoatopms, multiple 
database instances that have common WikiDatabase interface can be used as 
datasources.

This module is part of SuikaWiki.

=cut

package SuikaWiki::DB::Logical;
use strict;
our $VERSION=do{my @r=(q$Revision: 1.5 $=~/\d+/g);sprintf "%d."."%02d" x $#r,@r};
require SuikaWiki::DB::Util;
push our @ISA, 'SuikaWiki::DB::Util::template';

# new: inherited

sub get ($$$;%) {
  my ($self, $prop, $key, %opt) = @_;
  if ($self->{prop}->{$prop}) {
    local $Error::Depth = $Error::Depth + 1;
    unless ($self->{opened}->{$prop}) {
      $self->open_prop (prop => $prop);
    }
    return $self->{prop}->{$prop}->{-db}->get 
      ($self->{prop}->{$prop}->{-prop},
       $self->{prop}->{$prop}->{-key_mapper}->($self, $key), %opt);
  } else {
    return undef;
  }
}

sub set ($$$$;%) {
  my ($self, $prop, $key => $value, %opt) = @_;
  if ($self->{prop}->{$prop}) {
    local $Error::Depth = $Error::Depth + 1;
    unless ($self->{opened}->{$prop}) {
      $self->open_prop (prop => $prop);
    }
    $self->{prop}->{$prop}->{-db}->set
      ($self->{prop}->{$prop}->{-prop},
       $self->{prop}->{$prop}->{-key_mapper}->($self, $key) => $value, %opt);
  } else {
    report SuikaWiki::DB::Util::Error
      -type => 'KEY_SAVE',
      -object => $self, method => 'set',
      prop => $prop, key => $key;
  }
}

sub exist ($$$;%) {
  my ($self, $prop, $key, %opt) = @_;
  if ($self->{prop}->{$prop}) {
    local $Error::Depth = $Error::Depth + 1;
    unless ($self->{opened}->{$prop}) {
      $self->open_prop (prop => $prop);
    }
    return $self->{prop}->{$prop}->{-db}->exist
      ($self->{prop}->{$prop}->{-prop},
       $self->{prop}->{$prop}->{-key_mapper}->($self, $key), %opt);
  } else {
    return 0;
  }
}

sub delete ($$$;%) {
  my ($self, $prop, $key, %opt) = @_;
  if ($self->{prop}->{$prop}) {
    local $Error::Depth = $Error::Depth + 1;
    unless ($self->{opened}->{$prop}) {
      $self->open_prop (prop => $prop);
    }
    $self->{prop}->{$prop}->{-db}->delete
      ($self->{prop}->{$prop}->{-prop},
       $self->{prop}->{$prop}->{-key_mapper}->($self, $key), %opt);
  }
}

sub keys ($$;%) {
  my ($self, $prop, %opt) = @_;
  if ($self->{prop}->{$prop}) {
    local $Error::Depth = $Error::Depth + 1;
    unless ($self->{opened}->{$prop}) {
      $self->open_prop (prop => $prop);
    }
    $opt{-ns} = $self->{prop}->{$prop}->{-key_mapper}->($self, $opt{-ns});
    return
      map {$self->{prop}->{$prop}->{-key_rev_mapper}->($self, $_)}
      $self->{prop}->{$prop}->{-db}->keys
      ($self->{prop}->{$prop}->{-prop}, %opt);
  } else {
    return ();
  }
}

# close: Inherited

=head1 METHODS

This module provides common interface of SuikaWiki WikiDatabase
modules. See documentation of C<SuikaWiki::DB>.

In addition, this module implements additional methods.

=over 4

=item _set_prop_db ($prop_name, {options})

Addosiates actual database with property name of this logical (virtual)
database, or remove its association by specifying C<undef> instead of
C<{options}>.

Options:

=over 4

=item -db => $database_instance (REQUIRED)

Instance of database module, which implements common WikiDatabase interface.

=item -prop => $property_name (Default: same as $prop_name)

Property name used to access to $database_instance.  With this option,
different property name from datasource's one can be used,
eg. maps $prop_name eq 'subdb_foo' to $property_name eq 'foo'.

=item -key_mapper => sub ($self, $key) (Default: sub {$key})

Mapper from this virtual database's keyname to sub database's one.

=item -key_rev_mapper => sub ($self, $key) (Default: sub {$key})

Mapper from sub database's keyname to this virtual database's keyname.

Note that -key_mapper (-key_rev_mapper ($key)) need not equal to $key,
although it seems an unusual case.

=back

=cut

sub _set_prop_db ($$$) {
  my ($self, $prop, $db_and_opt) = @_;
  $self->{prop}->{$prop} = $db_and_opt;
  $db_and_opt->{-prop} = $prop unless defined $db_and_opt->{-prop};
  $db_and_opt->{-key_mapper} ||= \&__default_key_mapper;
  $db_and_opt->{-key_rev_mapper} ||= \&__default_key_rev_mapper;
  $db_and_opt->{-db_close} ||= sub {
    my %opt = @_;
    local $Error::Depth = $Error::Depth + 1;
    $opt{prop_info}->{-db}->close_prop (prop => $opt{prop_info}->{-prop});
  };
}

sub __default_key_mapper ($$) {
  #my ($self, $key) = @_;
  #$key;
  $_[1];
}
sub __default_key_rev_mapper ($$) {
  #my ($self, $key) = @_;
  #$key;
  $_[1];
}

sub ___open_prop ($$) {
  my ($self, $opt) = @_;
  return "0 but true" if defined $self->{prop}->{$opt->{prop}}->{-db};
  local $Error::Depth = $Error::Depth + 2;
  report SuikaWiki::DB::Util::Error
    -type => 'STOP_DB_PROP_CANT_OPEN__NOT_DEFINED',
    -object => $self, method => 'open_prop',
    prop => $opt->{prop}
    and return 0
    unless $self->{prop}->{$opt->{prop}}->{-db} or
           $self->{prop}->{$opt->{prop}}->{-db_open};
  $self->{prop}->{$opt->{prop}}->{-db} 
    = $self->{prop}->{$opt->{prop}}->{-db_open}->(metadb => $self);
  1;
}

sub ___close_prop ($$) {
  my ($self, $opt) = @_;
  return "0 but true" unless $self->{opened}->{$opt->{prop}};
  local $Error::Depth = $Error::Depth + 2;
  $self->{prop}->{$_}->{-db_close}->(metadb => $self, 
                                     prop_info => $self->{prop}->{$_});
  delete $self->{prop}->{$_}->{-db}
    if $self->{prop}->{$_}->{-db_open};
  1;
}

=back

=head1 LICENSE

Copyright 2003-2004 Wakaba <[email protected]>.  All rights reserved.

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.

=cut

1; # $Date: 2003/12/06 02:19:09 $
1
2	=head1 NAME
3
4	SuikaWiki::DB::Logical --- SuikaWiki WikiDatabase: Logical database consists of multiple datasources
5
6	=head1 DESCRIPTION
7
8	This module provides a logical database implementation. It does not itself have
9	physical datasource at all. With database property name asspcoatopms, multiple
10	database instances that have common WikiDatabase interface can be used as
11	datasources.
12
13	This module is part of SuikaWiki.
14
15	=cut
16
17	package SuikaWiki::DB::Logical;
18	use strict;
19	our $VERSION=do{my @r=(q$Revision: 1.5 $=~/\d+/g);sprintf "%d."."%02d" x $#r,@r};
20	require SuikaWiki::DB::Util;
21	push our @ISA, 'SuikaWiki::DB::Util::template';
22
23	# new: inherited
24
25	sub get ($$$;%) {
26	my ($self, $prop, $key, %opt) = @_;
27	if ($self->{prop}->{$prop}) {
28	local $Error::Depth = $Error::Depth + 1;
29	unless ($self->{opened}->{$prop}) {
30	$self->open_prop (prop => $prop);
31	}
32	return $self->{prop}->{$prop}->{-db}->get
33	($self->{prop}->{$prop}->{-prop},
34	$self->{prop}->{$prop}->{-key_mapper}->($self, $key), %opt);
35	} else {
36	return undef;
37	}
38	}
39
40	sub set ($$$$;%) {
41	my ($self, $prop, $key => $value, %opt) = @_;
42	if ($self->{prop}->{$prop}) {
43	local $Error::Depth = $Error::Depth + 1;
44	unless ($self->{opened}->{$prop}) {
45	$self->open_prop (prop => $prop);
46	}
47	$self->{prop}->{$prop}->{-db}->set
48	($self->{prop}->{$prop}->{-prop},
49	$self->{prop}->{$prop}->{-key_mapper}->($self, $key) => $value, %opt);
50	} else {
51	report SuikaWiki::DB::Util::Error
52	-type => 'KEY_SAVE',
53	-object => $self, method => 'set',
54	prop => $prop, key => $key;
55	}
56	}
57
58	sub exist ($$$;%) {
59	my ($self, $prop, $key, %opt) = @_;
60	if ($self->{prop}->{$prop}) {
61	local $Error::Depth = $Error::Depth + 1;
62	unless ($self->{opened}->{$prop}) {
63	$self->open_prop (prop => $prop);
64	}
65	return $self->{prop}->{$prop}->{-db}->exist
66	($self->{prop}->{$prop}->{-prop},
67	$self->{prop}->{$prop}->{-key_mapper}->($self, $key), %opt);
68	} else {
69	return 0;
70	}
71	}
72
73	sub delete ($$$;%) {
74	my ($self, $prop, $key, %opt) = @_;
75	if ($self->{prop}->{$prop}) {
76	local $Error::Depth = $Error::Depth + 1;
77	unless ($self->{opened}->{$prop}) {
78	$self->open_prop (prop => $prop);
79	}
80	$self->{prop}->{$prop}->{-db}->delete
81	($self->{prop}->{$prop}->{-prop},
82	$self->{prop}->{$prop}->{-key_mapper}->($self, $key), %opt);
83	}
84	}
85
86	sub keys ($$;%) {
87	my ($self, $prop, %opt) = @_;
88	if ($self->{prop}->{$prop}) {
89	local $Error::Depth = $Error::Depth + 1;
90	unless ($self->{opened}->{$prop}) {
91	$self->open_prop (prop => $prop);
92	}
93	$opt{-ns} = $self->{prop}->{$prop}->{-key_mapper}->($self, $opt{-ns});
94	return
95	map {$self->{prop}->{$prop}->{-key_rev_mapper}->($self, $_)}
96	$self->{prop}->{$prop}->{-db}->keys
97	($self->{prop}->{$prop}->{-prop}, %opt);
98	} else {
99	return ();
100	}
101	}
102
103	# close: Inherited
104
105	=head1 METHODS
106
107	This module provides common interface of SuikaWiki WikiDatabase
108	modules. See documentation of C<SuikaWiki::DB>.
109
110	In addition, this module implements additional methods.
111
112	=over 4
113
114	=item _set_prop_db ($prop_name, {options})
115
116	Addosiates actual database with property name of this logical (virtual)
117	database, or remove its association by specifying C<undef> instead of
118	C<{options}>.
119
120	Options:
121
122	=over 4
123
124	=item -db => $database_instance (REQUIRED)
125
126	Instance of database module, which implements common WikiDatabase interface.
127
128	=item -prop => $property_name (Default: same as $prop_name)
129
130	Property name used to access to $database_instance. With this option,
131	different property name from datasource's one can be used,
132	eg. maps $prop_name eq 'subdb_foo' to $property_name eq 'foo'.
133
134	=item -key_mapper => sub ($self, $key) (Default: sub {$key})
135
136	Mapper from this virtual database's keyname to sub database's one.
137
138	=item -key_rev_mapper => sub ($self, $key) (Default: sub {$key})
139
140	Mapper from sub database's keyname to this virtual database's keyname.
141
142	Note that -key_mapper (-key_rev_mapper ($key)) need not equal to $key,
143	although it seems an unusual case.
144
145	=back
146
147	=cut
148
149	sub _set_prop_db ($$$) {
150	my ($self, $prop, $db_and_opt) = @_;
151	$self->{prop}->{$prop} = $db_and_opt;
152	$db_and_opt->{-prop} = $prop unless defined $db_and_opt->{-prop};
153	$db_and_opt->{-key_mapper} \|\|= \&__default_key_mapper;
154	$db_and_opt->{-key_rev_mapper} \|\|= \&__default_key_rev_mapper;
155	$db_and_opt->{-db_close} \|\|= sub {
156	my %opt = @_;
157	local $Error::Depth = $Error::Depth + 1;
158	$opt{prop_info}->{-db}->close_prop (prop => $opt{prop_info}->{-prop});
159	};
160	}
161
162	sub __default_key_mapper ($$) {
163	#my ($self, $key) = @_;
164	#$key;
165	$_[1];
166	}
167	sub __default_key_rev_mapper ($$) {
168	#my ($self, $key) = @_;
169	#$key;
170	$_[1];
171	}
172
173	sub ___open_prop ($$) {
174	my ($self, $opt) = @_;
175	return "0 but true" if defined $self->{prop}->{$opt->{prop}}->{-db};
176	local $Error::Depth = $Error::Depth + 2;
177	report SuikaWiki::DB::Util::Error
178	-type => 'STOP_DB_PROP_CANT_OPEN__NOT_DEFINED',
179	-object => $self, method => 'open_prop',
180	prop => $opt->{prop}
181	and return 0
182	unless $self->{prop}->{$opt->{prop}}->{-db} or
183	$self->{prop}->{$opt->{prop}}->{-db_open};
184	$self->{prop}->{$opt->{prop}}->{-db}
185	= $self->{prop}->{$opt->{prop}}->{-db_open}->(metadb => $self);
186	1;
187	}
188
189	sub ___close_prop ($$) {
190	my ($self, $opt) = @_;
191	return "0 but true" unless $self->{opened}->{$opt->{prop}};
192	local $Error::Depth = $Error::Depth + 2;
193	$self->{prop}->{$_}->{-db_close}->(metadb => $self,
194	prop_info => $self->{prop}->{$_});
195	delete $self->{prop}->{$_}->{-db}
196	if $self->{prop}->{$_}->{-db_open};
197	1;
198	}
199
200	=back
201
202	=head1 LICENSE
203
204	Copyright 2003-2004 Wakaba <[email protected]>. All rights reserved.
205
206	This program is free software; you can redistribute it and/or
207	modify it under the same terms as Perl itself.
208
209	=cut
210
211	1; # $Date: 2003/12/06 02:19:09 $