package SQL::Translator;
#-----------------------------------------------------
-# $Id: Translator.pm,v 1.2 2002-03-07 14:06:20 dlc Exp $
-#-----------------------------------------------------
-# Copyright (C) 2002 Ken Y. Clark <kycl4rk@users.sourceforge.net>,
-# darren chamberlain <darren@cpan.org>
-#
-# This program is free software; you can redistribute it and/or
-# modify it under the terms of the GNU General Public License as
-# published by the Free Software Foundation; version 2.
-#
-# This program is distributed in the hope that it will be useful, but
-# WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-# General Public License for more details.
+# $Id: Translator.pm,v 1.3 2002-03-07 14:11:40 dlc Exp $
#
-# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
-# 02111-1307 USA
-# -------------------------------------------------------------------
-
-=head1 NAME
-
-SQL::Translator - convert schema from one database to another
-
-=head1 SYNOPSIS
-
- use SQL::Translator;
- my $translator = SQL::Translator->new;
- my $output = $translator->translate(
- parser => 'mysql',
- producer => 'oracle',
- file => $file,
- ) or die $translator->error;
- print $output;
-
-=head1 DESCRIPTION
-
-This module attempts to simplify the task of converting one database
-create syntax to another through the use of Parsers and Producers.
-The idea is that any Parser can be used with any Producer in the
-conversion process. So, if you wanted PostgreSQL-to-Oracle, you could
-just write the PostgreSQL parser and use an existing Oracle producer.
-
-Currently, the existing parsers use Parse::RecDescent, and the
-producers are just printing formatted output of the parsed data
-structure. New parsers don't necessarily have to use
-Parse::RecDescent, however, as long as the data structure conforms to
-what the producers are expecting. With this separation of code, it is
-hoped that developers will find it easy to add more database dialects
-by using what's written, writing only what they need, and then
-contributing their parsers or producers back to the project.
-
-=cut
+# File : SQL/Translator.pm
+# Programmer : Ken Y. Clark, kclark@logsoft.com
+# Created : 2002/02/27
+# Purpose : convert schema from one database to another
+#-----------------------------------------------------
use strict;
-use vars qw($VERSION $DEFAULT_SUB $DEBUG);
-$VERSION = sprintf "%d.%02d", q$Revision: 1.2 $ =~ /(\d+)\.(\d+)/;
-$DEBUG = 1 unless defined $DEBUG;
-
-$DEFAULT_SUB = sub { $_[0] } unless defined $DEFAULT_SUB;
-*isa = \&UNIVERSAL::isa;
+use vars qw( $VERSION );
+$VERSION = (qw$Revision: 1.3 $)[-1];
-=head1 CONSTRUCTOR
+use Data::Dumper;
-The constructor is called B<new>, and accepts a hash of options.
-Valid options are:
+use SQL::Translator::Parser::MySQL;
+use SQL::Translator::Parser::Sybase;
+use SQL::Translator::Producer::Oracle;
+use SQL::Translator::Producer::XML;
-=over 4
-
-=item parser (aka from)
-
-=item producer (aka to)
-
-=item filename
-
-=back
-
-All options are, well, optional; these attributes can be set via
-instance methods.
-
-=cut
+#
+# These are the inputs we can parse.
+#
+my %parsers = (
+ mysql => 'MySQL',
+ sybase => 'Sybase',
+);
-# {{{ new
+#
+# These are the formats we can produce.
+#
+my %producers = (
+ oracle => 'Oracle',
+ xml => 'XML',
+);
+#-----------------------------------------------------
sub new {
+#
+# Makes a new object. Intentionally made very bare as
+# it is used by all subclasses (unless they override,
+# of course).
+#
my $class = shift;
- my $args = isa($_[0], 'HASH') ? shift : { @_ };
- my $self = bless { } => $class;
-
- #
- # Set the parser and producer. If a 'parser' or 'from' parameter
- # is passed in, use that as the parser; if a 'producer' or 'to'
- # parameter is passed in, use that as the producer; both default
- # to $DEFAULT_SUB.
- #
- $self->parser( $args->{'parser'} || $args->{'from'} || $DEFAULT_SUB);
- $self->producer($args->{'producer'} || $args->{'to'} || $DEFAULT_SUB);
-
- #
- # Clear the error
- #
- $self->error_out("");
-
- return $self;
+ my %args = @_;
+ my $self = { %args };
+ return bless $self, $class;
}
-# }}}
-
-=head1 METHODS
-
-
-=head2 B<producer>
-
-The B<producer> method is an accessor/mutator, used to retrieve or
-define what subroutine is called to produce the output. A subroutine
-defined as a producer subroutine will be invoked as a function (not a
-method) and passed a data structure as its only argument. It is
-expected that the function transform the data structure to the output
-format, and return a string.
-
-When defining a producer, one of three things can be passed
-in: A full module name (e.g., My::Groovy::Parser), a module name
-relative to the SQL::Translator::Producer namespace (e.g., MySQL), or
-a reference to an anonymous subroutine. If a full module name is
-passed in, it is treated as a package, and a function called
-"transform" will be invoked as $modulename::transform.
-
- my $tr = SQL::Translator->new;
-
- # This will invoke My::Groovy::Producer::transform($data)
- $tr->producer("My::Groovy::Producer");
-
- # This will invoke SQL::Translator::Producer::Sybase::transform($data)
- $tr->producer("Sybase");
-
- # This will inoke the referenced subroutine directly
- $tr->producer(\&my_producer);
-
-=cut
-# TODO Make mod_perl-like assumptions about the name being passed in:
-# try to load the module; if that fails, pop off the last piece
-# (everything after the last ::) and try to load that; if that loads,
-# use the popped off piece as the function name, and not transform.
-
-# {{{ producer
-sub producer {
- my $self = shift;
- if (@_) {
- my $producer = shift;
- if ($producer =~ /::/) {
- load($producer) or die "Can't load $producer: $@";
- $self->{'producer'} = \&{ "$producer\::'producer'" };
- $self->debug("Got 'producer': $producer\::'producer'");
- } elsif (isa($producer, 'CODE')) {
- $self->{'producer'} = $producer;
- $self->debug("Got 'producer': code ref");
- } else {
- my $Pp = sprintf "SQL::Translator::Producer::$producer";
- load($Pp) or die "Can't load $Pp: $@";
- $self->{'producer'} = \&{ "$Pp\::translate" };
- $self->debug("Got producer: $Pp");
- }
- # At this point, $self->{'producer'} contains a subroutine
- # reference that is ready to run!
- }
- return $self->{'producer'};
-};
-# }}}
-=head2 B<parser>
-
-The B<parser> method defines or retrieves a subroutine that will be
-called to perform the parsing. The basic idea is the same as that of
-B<producer> (see above), except the default subroutine name is
-"parse", and will be invoked as $module_name::parse. Also, the parser
-subroutine will be passed a string containing the entirety of the data
-to be parsed.
-
- # Invokes SQL::Translator::Parser::MySQL::parse()
- $tr->parser("MySQL");
-
- # Invokes My::Groovy::Parser::parse()
- $tr->parser("My::Groovy::Parser");
-
- # Invoke an anonymous subroutine directly
- $tr->parser(sub {
- my $dumper = Data::Dumper->new([ $_[0] ], [ "SQL" ]);
- $dumper->Purity(1)->Terse(1)->Deepcopy(1);
- return $dumper->Dump;
- });
-
-=cut
+#-----------------------------------------------------
+sub error {
+#
+# Return the last error.
+#
+ return shift()->{'error'} || '';
+}
-# {{{ parser
-sub parser {
+#-----------------------------------------------------
+sub error_out {
+#
+# Record the error and return undef.
+#
my $self = shift;
- if (@_) {
- my $parser = shift;
- if ($parser =~ /::/) {
- load($parser) or die "Can't load $parser: $@";
- $self->{'parser'} = \&{ "$parser\::parse" };
- $self->debug("Got parser: $parser\::parse");
- } elsif (isa($parser, 'CODE')) {
- $self->{'parser'} = $parser;
- $self->debug("Got parser: code ref");
- } else {
- my $Pp = "SQL::Translator::Parser::$parser";
- load($Pp) or die "Can't load $Pp: $@";
- $self->{'parser'} = \&{ "$Pp\::parse" };
- $self->debug("Got parser: $Pp");
- }
- # At this point, $self->{$pp} contains a subroutine
- # reference that is ready to run!
+ if ( my $error = shift ) {
+ $self->{'error'} = $error;
}
- return $self->{'parser'};
+ return;
}
-# }}}
-
-=head2 B<translate>
-The B<translate> method calls the subroutines referenced by the
-B<parser> and B<producer> data members (described above). It accepts
-as arguments a number of things, in key => value format, including
-(potentially) a parser and a producer (they are passed directly to the
-B<parser> and B<producer> methods).
-
-Here is how the parameter list to B<translate> is parsed:
-
-=over
-
-=item *
-
-1 argument means it's the data to be parsed; which could be a string
-(filename), a reference to a GLOB (filehandle from which to read a
-string), a refernce to a scalar (a string stored in memory), or a
-reference to a hash (which means the same thing as below).
-
- # Parse the file /path/to/datafile
- my $output = $tr->translate("/path/to/datafile");
-
- # The same thing:
- my $fh = IO::File->new("/path/to/datafile");
- my $output = $tr->translate($fh);
-
- # Again, the same thing:
- my $fh = IO::File->new("/path/to/datafile");
- my $data = { local $/; <$fh> };
- my $output = $tr->translate(\$data);
-
-=item *
-
-> 1 argument means its a hash of things, and it might be setting a
-parser, producer, or datasource (this key is named "filename" or
-"file" if it's a file, or "data" for a GLOB or SCALAR reference).
-
- # As above, parse /path/to/datafile, but with different producers
- for my $prod ("MySQL", "XML", "Sybase") {
- print $tr->translate(
- producer => $prod,
- filename => "/path/to/datafile",
- );
- }
-
- # The filename hash key could also be:
- datasource => $fh,
-
- # or
- datasource => \$data,
-
-You get the idea.
-
-=back
-
-=cut
-
-# {{{ translate
+#-----------------------------------------------------
sub translate {
- my $self = shift;
- my ($args, $parser, $producer);
-
- if (@_ == 1) {
- if (isa($_[0], 'HASH')) {
- # Passed a hashref
- $args = $_[0];
- }
- elsif (isa($_[0], 'GLOB')) {
- # passed a filehandle; slurp it
- local $/;
- $args = { data => <$_[0]> };
- }
- elsif (isa($_[0], 'SCALAR')) {
- # passed a ref to a string; deref it
- $args = { data => ${$_[0]} };
- }
- else {
- # Not a ref, it's a filename
- $args = { filename => $_[0] };
- }
+#
+# Translates any number of given files.
+#
+ my ( $self, %args ) = @_;
+ my $from = $args{'from'} || '';
+ my $to = $args{'to'} || '';
+ my $input = $args{'input'} || [];
+ my $verbose = $args{'verbose'} || 0;
+ my $no_comments = $args{'no_comments'} || 0;
+
+ if ( exists $parsers{ $from } ) {
+ $self->{'from'} = $from;
+ warn "Using parser '$from.'\n" if $verbose;
}
else {
- # Should we check if @_ % 2, or just eat the errors if they occur?
- $args = { @_ };
+ my $msg = "The parsers '$from' is not valid.\n" .
+ "Please choose from the following list:\n";
+ $msg .= " $_\n" for sort keys %parsers;
+ return $self->error_out( $msg );
}
- if ((defined $args->{'filename'} ||
- defined $args->{'file'} ) && not $args->{'data'}) {
- local *FH;
- local $/;
-
- open FH, $args->{'filename'} or die $!;
- $args->{'data'} = <FH>;
- close FH or die $!;
+ if ( exists $producers{ $to } ) {
+ $self->{'to'} = $to;
+ warn "Using producer '$to.'\n" if $verbose;
}
-
- #
- # Last chance to bail out; if there's nothing in the data
- # key of %args, back out.
- #
- return unless defined $args->{'data'};
-
- #
- # Local reference to the parser subroutine
- #
- if ($parser = ($args->{'parser'} || $args->{'from'})) {
- $self->parser($parser);
- } else {
- $parser = $self->parser;
+ else {
+ my $msg = "The producer '$to' is not valid.\n" .
+ "Please choose from the following list:\n";
+ $msg .= " $_\n" for sort keys %producers;
+ return $self->error_out( $msg );
}
#
- # Local reference to the producer subroutine
+ # Slurp the entire text file we're parsing.
#
- if ($producer = ($args->{'producer'} || $args->{'to'})) {
- $self->producer($producer);
- } else {
- $producer = $self->producer;
+ my $parser = $self->parser;
+ my $producer = $self->producer;
+ my $data;
+ for my $file ( @$input ) {
+ warn "Parsing file '$file.'\n" if $verbose;
+ open my $fh, $file or return $self->error_out( "Can't read $file: $!" );
+ local $/;
+ $data = $parser->parse( <$fh> );
}
- #
- # Execute the parser, then execute the producer with that output
- #
- my $translated = $parser->($args->{'data'});
-
- return $producer->($translated);
+ warn "Data =\n", Dumper( $data ) if $verbose;
+ my $output = $producer->translate( $data );
}
-# }}}
-
-=head2 B<error>
-The error method returns the last error.
-
-=cut
-
-# {{{ error
#-----------------------------------------------------
-sub error {
+sub parser {
#
-# Return the last error.
+# Figures out which module to load based on the "from" argument
#
- return shift()->{'error'} || '';
-}
-# }}}
-
-=head2 B<error_out>
-
-Record the error and return undef. The error can be retrieved by
-calling programs using $tr->error.
-
-For Parser or Producer writers, primarily.
-
-=cut
-
-# {{{ error_out
-sub error_out {
my $self = shift;
- if ( my $error = shift ) {
- $self->{'error'} = $error;
+ unless ( $self->{'parser'} ) {
+ my $parser_module =
+ 'SQL::Translator::Parser::'.$parsers{ $self->{'from'} };
+ $self->{'parser'} = $parser_module->new;
}
- return;
+ return $self->{'parser'};
}
-# }}}
-
-=head2 B<debug>
-
-If the global variable $SQL::Translator::DEBUG is set to a true value,
-then calls to $tr->debug($msg) will be carped to STDERR. If $DEBUG is
-not set, then this method does nothing.
-
-=cut
-# {{{ debug
-use Carp qw(carp);
-sub debug {
+#-----------------------------------------------------
+sub producer {
+#
+# Figures out which module to load based on the "to" argument
+#
my $self = shift;
- carp @_ if ($DEBUG);
-}
-# }}}
-
-# {{{ load
-sub load {
- my $module = do { my $m = shift; $m =~ s[::][/]g; "$m.pm" };
- return 1 if $INC{$module};
-
- eval { require $module };
-
- return if ($@);
- return 1;
+ unless ( $self->{'producer'} ) {
+ my $from = $parsers{ $self->{'from'} };
+ my $producer_module =
+ 'SQL::Translator::Producer::'.$producers{ $self->{'to'} };
+ $self->{'producer'} = $producer_module->new( from => $from );
+ }
+ return $self->{'producer'};
}
-# }}}
1;
-__END__
#-----------------------------------------------------
# Rescue the drowning and tie your shoestrings.
# Henry David Thoreau
#-----------------------------------------------------
-=head1 AUTHOR
+=head1 NAME
-Ken Y. Clark, E<lt>kclark@logsoft.comE<gt>,
-darren chamberlain E<lt>darren@cpan.orgE<gt>
+SQL::Translator - convert schema from one database to another
-=head1 COPYRIGHT
+=head1 SYNOPSIS
-This program is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; version 2.
+ use SQL::Translator;
+ my $translator = SQL::Translator->new;
+ my $output = $translator->translate(
+ from => 'mysql',
+ to => 'oracle',
+ file => $file,
+ ) or die $translator->error;
+ print $output;
+
+=head1 DESCRIPTION
-This program is distributed in the hope that it will be useful, but
-WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-General Public License for more details.
+This module attempts to simplify the task of converting one database
+create syntax to another through the use of Parsers and Producers.
+The idea is that any Parser can be used with any Producer in the
+conversion process. So, if you wanted PostgreSQL-to-Oracle, you could
+just write the PostgreSQL parser and use an existing Oracle producer.
+
+Currently, the existing parsers use Parse::RecDescent, and the
+producers are just printing formatted output of the parsed data
+structure. New parsers don't necessarily have to use
+Parse::RecDescent, however, as long as the data structure conforms to
+what the producers are expecting. With this separation of code, it is
+hoped that developers will find it easy to add more database dialects
+by using what's written, writing only what they need, and then
+contributing their parsers or producers back to the project.
+
+=head1 AUTHOR
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
-USA
+Ken Y. Clark, kclark@logsoft.com
=head1 SEE ALSO
-L<perl>, L<Parse::RecDescent>
+perl(1).
=cut
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