lib/MOBY/mysql.pm

   1 #!/usr/bin/perl -w
   2 package MOBY::mysql;
   3 use strict;
   4 use Carp;
   5 use vars qw($AUTOLOAD @ISA);
   6
   7 =head1 NAME
   8
   9 MOBY::mysql - makes a MYSQL database connection.
  10
  11 =head1 SYNOPSIS
  12
  13  use MOBY::simple_output;
  14  my $dbh = MOBY::central_db_connection->new(
  15         db_connect_object => "MOBY::mysql",
  16         username => "myusername"
  17         password => "mypassword",
  18         dbname => "dbname",
  19         host => "dbhost",
  20  )
  21
  22  $sth = $dbh->prepare("select * from tablename");
  23
  24
  25 =cut
  26
  27 =head1 DESCRIPTION
  28
  29 makes a mysql conneciton to the database.  Should be created via
  30 a central_db_connection object only!
  31
  32 =head1 AUTHORS
  33
  34 Mark Wilkinson (mwilkinson@gene.pbi.nrc.ca)
  35
  36
  37 =cut
  38
  39 {
  40
  41         # Encapsulated:
  42         # DATA
  43         #___________________________________________________________
  44         #ATTRIBUTES
  45         my %_attr_data =    #                                   DEFAULT         ACCESSIBILITY
  46           ();
  47
  48         #_____________________________________________________________
  49         # METHODS, to operate on encapsulated class data
  50         # Is a specified object attribute accessible in a given mode
  51         sub _accessible {
  52                 my ( $self, $attr, $mode ) = @_;
  53                 $_attr_data{$attr}[1] =~ /$mode/;
  54         }
  55
  56         # Classwide default value for a specified object attribute
  57         sub _default_for {
  58                 my ( $self, $attr ) = @_;
  59                 $_attr_data{$attr}[0];
  60         }
  61
  62         # List of names of all specified object attributes
  63         sub _standard_keys {
  64                 keys %_attr_data;
  65         }
  66 }
  67
  68 sub new {
  69         my ( $caller, $dbname, $username, $password, $host, $port ) = @_;
  70         my $debug         = 0;
  71         my $caller_is_obj = ref($caller);
  72         return $caller if $caller_is_obj;
  73         my $class = $caller_is_obj || $caller;
  74         my $proxy;
  75         my $self = bless {}, $class;
  76         my ($dsn) = "DBI:mysql:$dbname:$host:$port";
  77         $debug
  78           && &_LOG("connecting to db with params $dbname, $username, $password\n");
  79         my $dbh = DBI->connect( $dsn, $username, $password, { RaiseError => 1 } )
  80           or die "can't connect to database";
  81         $debug && &_LOG("CONNECTED!\n");
  82         $self->databasehandle($dbh);
  83         return $self;
  84 }
  85
  86 sub AUTOLOAD {
  87         no strict "refs";
  88         my ( $self, $newval ) = @_;
  89         $AUTOLOAD =~ /.*::(\w+)/;
  90         my $attr = $1;
  91         if ( $self->_accessible( $attr, 'write' ) ) {
  92                 *{$AUTOLOAD} = sub {
  93                         if ( defined $_[1] ) { $_[0]->{$attr} = $_[1] }
  94                         return $_[0]->{$attr};
  95                 };    ### end of created subroutine
  96 ###  this is called first time only
  97                 if ( defined $newval ) {
  98                         $self->{$attr} = $newval;
  99                 }
 100                 return $self->{$attr};
 101         } elsif ( $self->_accessible( $attr, 'read' ) ) {
 102                 *{$AUTOLOAD} = sub {
 103                         return $_[0]->{$attr};
 104                 };    ### end of created subroutine
 105                 return $self->{$attr};
 106         }
 107
 108         # Must have been a mistake then...
 109         croak "No such method: $AUTOLOAD";
 110 }
 111 sub DESTROY { }
 112 1;