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joko |
1.5 |
# $Id: Storage.pm,v 1.4 2002/10/27 18:35:07 joko Exp $ |
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joko |
1.4 |
# |
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# Copyright (c) 2002 Andreas Motl <andreas.motl@ilo.de> |
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# See COPYRIGHT section in pod text below for usage and distribution rights. |
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cvsjoko |
1.1 |
################################# |
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joko |
1.4 |
# $Log: Storage.pm,v $ |
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joko |
1.5 |
# Revision 1.4 2002/10/27 18:35:07 joko |
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# + added pod |
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# |
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joko |
1.4 |
# Revision 1.3 2002/10/25 11:40:37 joko |
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# + enhanced robustness |
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# + more logging for debug-levels |
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# + sub dropDb |
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joko |
1.2 |
# |
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joko |
1.3 |
# Revision 1.2 2002/10/17 00:04:29 joko |
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# + sub createDb |
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# + sub isConnected |
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# + bugfixes regarding "deep recursion" stuff |
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# |
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joko |
1.2 |
# Revision 1.1 2002/10/10 03:43:12 cvsjoko |
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# + new |
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cvsjoko |
1.1 |
# |
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################################# |
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joko |
1.3 |
# aim_V1: should encapsulate Tangram, DBI, DBD::CSV and LWP:: to access them in an unordinary way ;) |
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# aim_V2: introduce a generic layered structure, refactor *SUBLAYER*-stuff, make (e.g.) this possible: |
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# - Perl Data::Storage[DBD::CSV] -> Perl LWP:: -> Internet HTTP/FTP/* -> Host Daemon -> csv-file |
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joko |
1.4 |
BEGIN { |
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$Data::Storage::VERSION = 0.01; |
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} |
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joko |
1.5 |
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joko |
1.4 |
=head1 NAME |
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Data::Storage - Interface for accessing various Storage implementations for Perl in an independent way |
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=head1 SYNOPSIS |
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... the basic way: |
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... via inheritance: |
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use Data::Storage; |
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my $proxyObj = new HttpProxy; |
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$proxyObj->{url} = $url; |
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$proxyObj->{payload} = $content; |
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$self->{storage}->insert($proxyObj); |
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use Data::Storage; |
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my $proxyObj = HttpProxy->new( |
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url => $url, |
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payload => $content, |
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); |
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$self->{storage}->insert($proxyObj); |
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=head2 NOTE |
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This module heavily relies on DBI and Tangram, but adds a lot of additional bugs and quirks. |
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Please look at their documentation and this code for additional information. |
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=cut |
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# The POD text continues at the end of the file. |
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cvsjoko |
1.1 |
package Data::Storage; |
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use strict; |
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use warnings; |
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use Data::Storage::Locator; |
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joko |
1.5 |
my $TRACELEVEL = 0; |
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cvsjoko |
1.1 |
# get logger instance |
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my $logger = Log::Dispatch::Config->instance; |
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sub new { |
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my $invocant = shift; |
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my $class = ref($invocant) || $invocant; |
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#my @args = normalizeArgs(@_); |
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my $arg_locator = shift; |
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my $arg_options = shift; |
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#my $self = { STORAGEHANDLE => undef, @_ }; |
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my $self = { STORAGEHANDLE => undef, locator => $arg_locator, options => $arg_options }; |
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$logger->debug( __PACKAGE__ . "[$self->{locator}->{type}]" . "->new(@_)" ); |
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return bless $self, $class; |
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} |
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sub AUTOLOAD { |
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1.2 |
# since this is a core function acting as dispatcher to $self->{STORAGEHANDLE}, |
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# some sophisticated handling and filtering is needed to avoid things like |
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# - Deep recursion on subroutine "Data::Storage::AUTOLOAD" |
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# - Deep recursion on subroutine "Data::Storage::Handler::Abstract::AUTOLOAD" |
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# - Deep recursion on anonymous subroutine at [...] |
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# we also might filter log messages caused by logging itself in "advanced logging of AUTOLOAD calls" |
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cvsjoko |
1.1 |
my $self = shift; |
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our $AUTOLOAD; |
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# ->DESTROY would - if not declared - trigger an AUTOLOAD also |
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return if $AUTOLOAD =~ m/::DESTROY$/; |
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my $method = $AUTOLOAD; |
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$method =~ s/^.*:://; |
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joko |
1.5 |
# advanced logging of AUTOLOAD calls ... |
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# ... nice but do it only when TRACING (TODO) is enabled |
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if ($TRACELEVEL) { |
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my $logstring = ""; |
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$logstring .= __PACKAGE__ . "[$self->{locator}->{type}]" . "->" . $method; |
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#print "count: ", $#_, "\n"; |
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#$logstring .= Dumper(@_) if ($#_ != -1); |
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my $tabcount = int( (80 - length($logstring)) / 10 ); |
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$logstring .= "\t" x $tabcount . "(AUTOLOAD)"; |
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# TODO: only ok if logstring doesn't contain |
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# e.g. "Data::Storage[Tangram]->insert(SystemEvent=HASH(0x5c0034c)) (AUTOLOAD)" |
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# but that would be way too specific as long as we don't have an abstract handler for this ;) |
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$logger->debug( $logstring ); |
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} |
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joko |
1.2 |
# filtering AUTOLOAD calls |
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cvsjoko |
1.1 |
if ($self->_filter_AUTOLOAD($method)) { |
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$self->_accessStorage(); |
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$self->{STORAGEHANDLE}->$method(@_); |
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} |
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} |
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sub _filter_AUTOLOAD { |
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my $self = shift; |
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my $method = shift; |
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if ($self->{options}->{protected}) { |
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if ($method eq 'disconnect') { |
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return; |
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} |
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} |
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return 1; |
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} |
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sub normalizeArgs { |
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my %args = @_; |
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if (!$args{dsn} && $args{meta}{dsn}) { |
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$args{dsn} = $args{meta}{dsn}; |
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} |
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my @result = %args; |
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return @result; |
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} |
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sub _accessStorage { |
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my $self = shift; |
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# TODO: to some tracelevel! |
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joko |
1.5 |
if ($TRACELEVEL) { |
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$logger->debug( __PACKAGE__ . "[$self->{locator}->{type}]" . "->_accessStorage()" ); |
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} |
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cvsjoko |
1.1 |
if (!$self->{STORAGEHANDLE}) { |
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$self->_createStorageHandle(); |
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} |
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} |
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sub _createStorageHandle { |
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my $self = shift; |
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my $type = $self->{locator}->{type}; |
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$logger->debug( __PACKAGE__ . "[$type]" . "->_createStorageHandle()" ); |
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my $pkg = "Data::Storage::Handler::" . $type . ""; |
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# propagate args to handler |
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# needs some more thoughts! (not only "dbi" to Tangram, when (in future) db is not more the common case) |
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if ($type eq 'DBI') { |
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joko |
1.2 |
use Data::Storage::Handler::DBI; |
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cvsjoko |
1.1 |
#my @args = %{$self->{locator}->{dbi}}; |
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my @args = %{$self->{locator}}; |
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joko |
1.3 |
# create new storage handle |
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cvsjoko |
1.1 |
$self->{STORAGEHANDLE} = $pkg->new( @args ); |
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} |
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if ($type eq 'Tangram') { |
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joko |
1.2 |
use Data::Storage::Handler::Tangram; |
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cvsjoko |
1.1 |
#$self->{STORAGEHANDLE} = $pkg->new( dsn => $self->{locator}->{dbi}->{dsn} ); |
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#my @args = %{$self->{locator}->{dbi}}; |
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my @args = %{$self->{locator}}; |
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joko |
1.3 |
# create new storage handle |
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cvsjoko |
1.1 |
$self->{STORAGEHANDLE} = $pkg->new( @args ); |
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joko |
1.3 |
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cvsjoko |
1.1 |
#$self->{STORAGEHANDLE_UNDERLYING} = $self->{STORAGEHANDLE}->getUnderlyingStorage(); |
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#$self->{STORAGEHANDLE_UNDERLYING}->_configureCOREHANDLE(); |
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} |
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} |
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sub addLogDispatchHandler { |
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my $self = shift; |
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my $name = shift; |
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my $package = shift; |
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joko |
1.3 |
my $logger1 = shift; |
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cvsjoko |
1.1 |
my $objectCreator = shift; |
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#$logger->add( Log::Dispatch::Tangram->new( name => $name, |
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$logger->add( $package->new( name => $name, |
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#min_level => 'debug', |
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min_level => 'info', |
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storage => $self, |
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objectCreator => $objectCreator, |
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fields => { |
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message => 'usermsg', |
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timestamp => 'stamp', |
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level => 'level', |
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name => 'code', |
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}, |
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filter_patterns => [ '->insert\(SystemEvent=' ], |
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#filter_patterns => [ 'SystemEvent' ], |
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#format => '[%d] [%p] %m%n', |
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) ); |
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} |
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sub removeLogDispatchHandler { |
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my $self = shift; |
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my $name = shift; |
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joko |
1.3 |
#my $logger = shift; |
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cvsjoko |
1.1 |
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$logger->remove($name); |
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} |
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sub getDbName { |
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my $self = shift; |
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my $dsn = $self->{locator}->{dbi}->{dsn}; |
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$dsn =~ m/database=(.+?);/; |
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my $database_name = $1; |
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return $database_name; |
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} |
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sub testDsn { |
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my $self = shift; |
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my $dsn = $self->{locator}->{dbi}->{dsn}; |
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my $result; |
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if ( my $dbh = DBI->connect($dsn, '', '', { |
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PrintError => 0, |
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} ) ) { |
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$dbh->disconnect(); |
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return 1; |
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} else { |
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joko |
1.2 |
$logger->error( __PACKAGE__ . "[$self->{locator}->{type}]" . "->testDsn(): " . "DBI-error: " . $DBI::errstr ); |
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} |
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} |
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sub createDb { |
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my $self = shift; |
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my $dsn = $self->{locator}->{dbi}->{dsn}; |
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joko |
1.3 |
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$logger->debug( __PACKAGE__ . "->createDb( dsn $dsn )" ); |
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joko |
1.2 |
$dsn =~ s/database=(.+?);//; |
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my $database_name = $1; |
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my $ok; |
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if ( my $dbh = DBI->connect($dsn, '', '', { |
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PrintError => 0, |
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} ) ) { |
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if ($database_name) { |
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if ($dbh->do("CREATE DATABASE $database_name;")) { |
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$ok = 1; |
280 |
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} |
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} |
282 |
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$dbh->disconnect(); |
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cvsjoko |
1.1 |
} |
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joko |
1.2 |
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return $ok; |
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joko |
1.3 |
} |
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sub dropDb { |
290 |
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my $self = shift; |
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my $dsn = $self->{locator}->{dbi}->{dsn}; |
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$logger->debug( __PACKAGE__ . "->dropDb( dsn $dsn )" ); |
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$dsn =~ s/database=(.+?);//; |
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my $database_name = $1; |
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my $ok; |
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if ( my $dbh = DBI->connect($dsn, '', '', { |
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PrintError => 0, |
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} ) ) { |
303 |
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if ($database_name) { |
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if ($dbh->do("DROP DATABASE $database_name;")) { |
305 |
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$ok = 1; |
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} |
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} |
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$dbh->disconnect(); |
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} |
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return $ok; |
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joko |
1.2 |
} |
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sub isConnected { |
315 |
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my $self = shift; |
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return 1 if $self->{STORAGEHANDLE}; |
317 |
cvsjoko |
1.1 |
} |
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joko |
1.4 |
1; |
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__END__ |
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=head1 DESCRIPTION |
324 |
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Data::Storage is module for a accessing various "data structures" stored inside |
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various "data containers". It sits on top of DBI and/or Tangram. |
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=head1 AUTHORS / COPYRIGHT |
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The Data::Storage module is Copyright (c) 2002 Andreas Motl. |
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All rights reserved. |
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You may distribute it under the terms of either the GNU General Public |
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License or the Artistic License, as specified in the Perl README file. |
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=head1 ACKNOWLEDGEMENTS |
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Larry Wall and the C<perl5-porters> for Perl, |
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Tim Bunce for DBI, Jean-Louis Leroy for Tangram and Set::Object, |
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Sam Vilain for Class::Tangram. |
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=head1 SUPPORT / WARRANTY |
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Data::Storage is free software. IT COMES WITHOUT WARRANTY OF ANY KIND. |
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=head1 TODO |
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=head2 Handle the following errors/cases: |
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=head3 "DBI-Error [Tangram]: DBD::mysql::st execute failed: Unknown column 't1.requestdump' in 'field list'" |
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... occours when operating on object-attributes not introduced yet: |
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this should be detected and appended/replaced through: |
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"Schema-Error detected, maybe (just) an inconsistency. |
360 |
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Please check if your declaration in schema-module "a" matches structure in database "b" or try to run" |
361 |
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db_setup.pl --dbkey=import --action=deploy |
362 |
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363 |
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=head3 Compare schema (structure diff) with database ... |
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365 |
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... when issuing "db_setup.pl --dbkey=import --action=deploy" |
366 |
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on a database with an already deployed schema, use an additional "--update" then |
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to lift the schema inside the database to the current declared schema. |
368 |
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You will have to approve removals and changes on field-level while |
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new objects and new fields are introduced silently without any interaction needed. |
370 |
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In future versions there may be additional options to control silent processing of |
371 |
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removals and changes. |
372 |
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See this CRUD-table applying to the actions occouring on Classes and Class variables when deploying schemas, |
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don't mix this up with CRUD-actions on Objects, these are already handled by (e.g.) Tangram itself. |
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Classes: |
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C create -> yes, handled automatically |
376 |
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R retrieve -> no, not subject of this aspect since it is about deployment only |
377 |
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U update -> yes, automatically for Class meta-attributes, yes/no for Class variables (look at the rules down here) |
378 |
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D delete -> yes, just by user-interaction |
379 |
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Class variables: |
380 |
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C create -> yes, handled automatically |
381 |
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R retrieve -> no, not subject of this aspect since it is about deployment only |
382 |
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U update -> yes, just by user-interaction; maybe automatically if it can be determined that data wouldn't be lost |
383 |
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D delete -> yes, just by user-interaction |
384 |
joko |
1.5 |
|
385 |
|
|
It's all about not to be able to loose data simply while this is in pre-alpha stage. |
386 |
|
|
And loosing data by being able to modify and redeploy schemas easily is definitely quite easy. |
387 |
|
|
|
388 |
|
|
As we can see, creations of Classes and new Class variables is handled |
389 |
|
|
automatically and this is believed to be the most common case under normal circumstances. |
390 |
joko |
1.4 |
|
391 |
|
|
|
392 |
|
|
=head2 Introduce some features: |
393 |
|
|
|
394 |
joko |
1.5 |
- Get this stuff together with UML (Unified Modeling Language) and/or standards from ODMG. |
395 |
|
|
- Make it possible to load/save schemas in XMI (XML Metadata Interchange), |
396 |
|
|
which seems to be most commonly used today, perhaps handle objects with OIFML. |
397 |
|
|
Integrate/bundle this with a web-/html-based UML modeling tool or |
398 |
|
|
some other interesting stuff like the "Co-operative UML Editor" from Uni Darmstadt. (web-/java-based) |
399 |
|
|
- Enable Round Trip Engineering. Keep code and diagrams in sync. Don't annoy/bother the programmers. |
400 |
|
|
- Add some more handlers: |
401 |
|
|
- look at DBD::CSV, Text::CSV, XML::CSV, XML::Excel |
402 |
|
|
- Add some more locations/locators: |
403 |
|
|
- PerlDAV: http://www.webdav.org/perldav/ |
404 |
|
|
- Move to t3, use InCASE |
405 |
joko |
1.4 |
|
406 |
|
|
|
407 |
|
|
=head3 Links: |
408 |
|
|
|
409 |
joko |
1.5 |
Specs: |
410 |
joko |
1.4 |
UML 1.3 Spec: http://cgi.omg.org/cgi-bin/doc?ad/99-06-08.pdf |
411 |
|
|
XMI 1.1 Spec: http://cgi.omg.org/cgi-bin/doc?ad/99-10-02.pdf |
412 |
|
|
XMI 2.0 Spec: http://cgi.omg.org/docs/ad/01-06-12.pdf |
413 |
|
|
ODMG: http://odmg.org/ |
414 |
|
|
OIFML: http://odmg.org/library/readingroom/oifml.pdf |
415 |
|
|
|
416 |
joko |
1.5 |
CASE Tools: |
417 |
|
|
Rational Rose (commercial): http://www.rational.com/products/rose/ |
418 |
|
|
Together (commercial): http://www.oi.com/products/controlcenter/index.jsp |
419 |
|
|
InCASE - Tangram-based Universal Object Editor |
420 |
|
|
Sybase PowerDesigner: http://www.sybase.com/powerdesigner |
421 |
|
|
|
422 |
|
|
UML Editors: |
423 |
|
|
Fujaba (free, university): http://www.fujaba.de/ |
424 |
|
|
ArgoUML (free): http://argouml.tigris.org/ |
425 |
|
|
Poseidon (commercial): http://www.gentleware.com/products/poseidonDE.php3 |
426 |
|
|
Co-operative UML Editor (research): http://www.darmstadt.gmd.de/concert/activities/internal/umledit.html |
427 |
|
|
Metamill (commercial): http://www.metamill.com/ |
428 |
|
|
Violet (university, research, education): http://www.horstmann.com/violet/ |
429 |
|
|
PyUt (free): http://pyut.sourceforge.net/ |
430 |
|
|
(Dia (free): http://www.lysator.liu.se/~alla/dia/) |
431 |
|
|
UMLet (free, university): http://www.swt.tuwien.ac.at/umlet/index.html |
432 |
|
|
Voodoo (free): http://voodoo.sourceforge.net/ |
433 |
|
|
|
434 |
|
|
UML Tools: |
435 |
|
|
http://www.objectsbydesign.com/tools/umltools_byPrice.html |
436 |
|
|
|
437 |
|
|
Further readings: |
438 |
joko |
1.4 |
http://www.google.com/search?q=web+based+uml+editor&hl=en&lr=&ie=UTF-8&oe=UTF-8&start=10&sa=N |
439 |
|
|
http://www.fernuni-hagen.de/DVT/Aktuelles/01FHHeidelberg.pdf |
440 |
|
|
http://www.enhyper.com/src/documentation/ |
441 |
|
|
http://cis.cs.tu-berlin.de/Dokumente/Diplomarbeiten/2001/skinner.pdf |
442 |
|
|
http://citeseer.nj.nec.com/vilain00diagrammatic.html |
443 |
|
|
http://archive.devx.com/uml/articles/Smith01/Smith01-3.asp |
444 |
|
|
|