package SQL::Translator;
- #-----------------------------------------------------
- # $Id: Translator.pm,v 1.3 2002-03-07 14:11:40 dlc Exp $
+ # ----------------------------------------------------------------------
-# $Id: Translator.pm,v 1.3.2.3 2002-03-18 20:35:51 dlc Exp $
++# $Id: Translator.pm,v 1.4 2002-03-21 18:50:53 dlc Exp $
+ # ----------------------------------------------------------------------
+ # Copyright (C) 2002 Ken Y. Clark <kycl4rk@users.sourceforge.net>,
+ # darren chamberlain <darren@cpan.org>
#
- # File : SQL/Translator.pm
- # Programmer : Ken Y. Clark, kclark@logsoft.com
- # Created : 2002/02/27
- # Purpose : convert schema from one database to another
- #-----------------------------------------------------
+ # 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.
+ #
+ # 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(
+ from => "MySQL",
+ to => "Oracle",
+ filename => $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 would
+ use the PostgreSQL parser and the Oracle producer.
+
+ Currently, the existing parsers use Parse::RecDescent, but this not
+ a requirement, or even a recommendation. New parser modules don't
+ necessarily have to use Parse::RecDescent, as long as the module
+ implements the appropriate API. 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
use strict;
- use vars qw( $VERSION );
- $VERSION = (qw$Revision: 1.3 $)[-1];
+ use vars qw($VERSION $DEFAULT_SUB $DEBUG);
-$VERSION = sprintf "%d.%02d", q$Revision: 1.3.2.3 $ =~ /(\d+)\.(\d+)/;
++$VERSION = sprintf "%d.%02d", q$Revision: 1.4 $ =~ /(\d+)\.(\d+)/;
+ $DEBUG = 1 unless defined $DEBUG;
- use Data::Dumper;
+ # ----------------------------------------------------------------------
+ # The default behavior is to "pass through" values (note that the
+ # SQL::Translator instance is the first value ($_[0]), and the stuff
+ # to be parsed is the second value ($_[1])
+ # ----------------------------------------------------------------------
+ $DEFAULT_SUB = sub { $_[1] } unless defined $DEFAULT_SUB;
- use SQL::Translator::Parser::MySQL;
- use SQL::Translator::Parser::Sybase;
- use SQL::Translator::Producer::Oracle;
- use SQL::Translator::Producer::XML;
+ *isa = \&UNIVERSAL::isa;
- #
- # These are the inputs we can parse.
- #
- my %parsers = (
- mysql => 'MySQL',
- sybase => 'Sybase',
- );
+ use Carp qw(carp);
- #
- # These are the formats we can produce.
- #
- my %producers = (
- oracle => 'Oracle',
- xml => 'XML',
- );
+ =head1 CONSTRUCTOR
- #-----------------------------------------------------
- sub new {
+ The constructor is called B<new>, and accepts a optional hash of options.
+ Valid options are:
+
+ =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. Internally, they are; no (non-syntactical)
+ advantage is gained by passing options to the constructor.
+
+ =cut
+
+ # {{{ new
+ # ----------------------------------------------------------------------
+ # new([ARGS])
+ # The constructor.
#
- # Makes a new object. Intentionally made very bare as
- # it is used by all subclasses (unless they override,
- # of course).
+ # new takes an optional hash of arguments. These arguments may
+ # include a parser, specified with the keys "parser" or "from",
+ # and a producer, specified with the keys "producer" or "to".
#
+ # The values that can be passed as the parser or producer are
+ # given directly to the parser or producer methods, respectively.
+ # See the appropriate method description below for details about
+ # what each expects/accepts.
+ #
+ # TODO
+ # * Support passing an input (filename or string) as with
+ # translate
+ # ----------------------------------------------------------------------
+ sub new {
my $class = shift;
- my %args = @_;
- my $self = { %args };
- return bless $self, $class;
- }
+ my $args = isa($_[0], 'HASH') ? shift : { @_ };
+ my $self = bless { } => $class;
- #-----------------------------------------------------
- sub error {
- #
- # Return the last error.
- #
- return shift()->{'error'} || '';
+ # ------------------------------------------------------------------
+ # 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;
}
+ # }}}
- #-----------------------------------------------------
- sub error_out {
- #
- # Record the error and return undef.
- #
+ =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 will be invoked as a function (not a method) and
+ passed 2 parameters: its container SQL::Translator instance and a
+ data structure. It is expected that the function transform the data
+ structure to a string. The SQL::Transformer instance is provided for
+ informational purposes; for example, the type of the parser can be
+ retrieved using the B<parser_type> method, and the B<error> and
+ B<debug> methods can be called when needed.
+
+ When defining a producer, one of several things can be passed
+ in: A module name (e.g., My::Groovy::Producer), a module name
+ relative to the SQL::Translator::Producer namespace (e.g., MySQL), a
+ module name and function combination (My::Groovy::Producer::transmogrify),
+ or a reference to an anonymous subroutine. If a full module name is
+ passed in (for the purposes of this method, a string containing "::"
+ is considered to be a module name), it is treated as a package, and a
+ function called "produce" will be invoked: $modulename::produce. If
+ $modulename cannot be loaded, the final portion is stripped off and
+ treated as a function. In other words, if there is no file named
+ My/Groovy/Producer/transmogrify.pm, SQL::Translator will attempt to load
+ My/Groovy/Producer.pm and use transmogrify as the name of the function,
+ instead of the default "produce".
+
+ my $tr = SQL::Translator->new;
+
+ # This will invoke My::Groovy::Producer::produce($tr, $data)
+ $tr->producer("My::Groovy::Producer");
+
+ # This will invoke SQL::Translator::Producer::Sybase::produce($tr, $data)
+ $tr->producer("Sybase");
+
+ # This will invoke My::Groovy::Producer::transmogrify($tr, $data),
+ # assuming that My::Groovy::Producer::transmogrify is not a module
+ # on disk.
+ # $tr->producer("My::Groovy::Producer::transmogrify);
+
+ # This will invoke the referenced subroutine directly, as
+ # $subref->($tr, $data);
+ $tr->producer(\&my_producer);
+
+ There is also a method named B<producer_type>, which is a string
+ containing the classname to which the above B<produce> function
+ belongs. In the case of anonymous subroutines, this method returns
+ the string "CODE".
+
+ =cut
+
+ # {{{ producer and producer_type
+ sub producer {
my $self = shift;
- if ( my $error = shift ) {
- $self->{'error'} = $error;
- }
- return;
+
+ # {{{ producer as a mutator
+ if (@_) {
+ my $producer = shift;
+
+ # {{{ Passed a module name (string containing "::")
+ if ($producer =~ /::/) {
+ my $func_name;
+
+ # {{{ Module name was passed directly
+ # We try to load the name; if it doesn't load, there's
+ # a possibility that it has a function name attached to
+ # it.
+ if (load($producer)) {
+ $func_name = "produce";
+ } # }}}
+
+ # {{{ Module::function was passed
+ else {
+ # Passed Module::Name::function; try to recover
+ my @func_parts = split /::/, $producer;
+ $func_name = pop @func_parts;
+ $producer = join "::", @func_parts;
+
+ # If this doesn't work, then we have a legitimate
+ # problem.
+ load($producer) or die "Can't load $producer: $@";
+ } # }}}
+
+ # {{{ get code reference and assign
+ $self->{'producer'} = \&{ "$producer\::$func_name" };
+ $self->{'producer_type'} = $producer;
+ $self->debug("Got 'producer': $producer\::$func_name");
+ # }}}
+ } # }}}
+
+ # {{{ passed an anonymous subroutine reference
+ elsif (isa($producer, 'CODE')) {
+ $self->{'producer'} = $producer;
+ $self->{'producer_type'} = "CODE";
+ $self->debug("Got 'producer': code ref");
+ } # }}}
+
+ # {{{ passed a string containing no "::"; relative package name
+ else {
+ my $Pp = sprintf "SQL::Translator::Producer::$producer";
+ load($Pp) or die "Can't load $Pp: $@";
+ $self->{'producer'} = \&{ "$Pp\::produce" };
+ $self->{'producer_type'} = $Pp;
+ $self->debug("Got producer: $Pp");
+ } # }}}
+
+ # At this point, $self->{'producer'} contains a subroutine
+ # reference that is ready to run
+ } # }}}
+
+ return $self->{'producer'};
+ };
+
+ sub producer_type { $_[0]->{'producer_type'} }
+ # }}}
+
+ =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 $module_name::parse($tr, $data).
+ Also, the parser subroutine will be passed a string containing the
+ entirety of the data to be parsed (or possibly a reference to a string?).
+
+ # 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([ $_[1] ], [ "SQL" ]);
+ $dumper->Purity(1)->Terse(1)->Deepcopy(1);
+ return $dumper->Dump;
+ });
+
+ =cut
+
+ # {{{ parser and parser_type
+ sub parser {
+ my $self = shift;
+
+ # {{{ parser as a mutator
+ if (@_) {
+ my $parser = shift;
+
+ # {{{ Passed a module name (string containing "::")
+ if ($parser =~ /::/) {
+ my $func_name;
+
+ # {{{ Module name was passed directly
+ # We try to load the name; if it doesn't load, there's
+ # a possibility that it has a function name attached to
+ # it.
+ if (load($parser)) {
+ $func_name = "parse";
+ } # }}}
+
+ # {{{ Module::function was passed
+ else {
+ # Passed Module::Name::function; try to recover
+ my @func_parts = split /::/, $parser;
+ $func_name = pop @func_parts;
+ $parser = join "::", @func_parts;
+
+ # If this doesn't work, then we have a legitimate
+ # problem.
+ load($parser) or die "Can't load $parser: $@";
+ } # }}}
+
+ # {{{ get code reference and assign
+ $self->{'parser'} = \&{ "$parser\::$func_name" };
+ $self->{'parser_type'} = $parser;
+ $self->debug("Got parser: $parser\::$func_name");
+ # }}}
+ } # }}}
+
+ # {{{ passed an anonymous subroutine reference
+ elsif (isa($parser, 'CODE')) {
+ $self->{'parser'} = $parser;
+ $self->{'parser_type'} = "CODE";
+ $self->debug("Got 'parser': code ref");
+ } # }}}
+
+ # {{{ passed a string containing no "::"; relative package name
+ else {
+ my $Pp = sprintf "SQL::Translator::Parser::$parser";
+ load($Pp) or die "Can't load $Pp: $@";
+ $self->{'parser'} = \&{ "$Pp\::parse" };
+ $self->{'parser_type'} = $Pp;
+ $self->debug("Got parser: $Pp");
+ } # }}}
+
+ # At this point, $self->{'parser'} contains a subroutine
+ # reference that is ready to run
+ } # }}}
+
+
+ return $self->{'parser'};
}
- #-----------------------------------------------------
+ sub parser_type { $_[0]->{'parser_type'} }
+ # }}}
+
+ =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) or a refernce to a scalar (a string stored in memory), or a
+ reference to a hash, which is parsed as being more than one argument
+ (see next section).
+
+ # Parse the file /path/to/datafile
+ my $output = $tr->translate("/path/to/datafile");
+
+ # Parse the data contained in the string $data
+ my $output = $tr->translate(\$data);
+
+ =item *
+
+ More than 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 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 => \$data,
+
+ You get the idea.
+
+ =back
+
+ =cut
+
+ # {{{ translate
sub translate {
- #
- # 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;
+ my $self = shift;
+ my ($args, $parser, $producer);
+
+ if (@_ == 1) {
+ if (isa($_[0], 'HASH')) {
+ # Passed a hashref
+ $self->debug("translate: Got a hashref");
+ $args = $_[0];
+ }
+ elsif (isa($_[0], 'SCALAR')) {
+ # passed a ref to a string; deref it
+ $self->debug("translate: Got a SCALAR reference (string)");
+ $args = { data => ${$_[0]} };
+ }
+ elsif (! ref $_[0]) {
+ # Not a ref, it's a filename
+ $self->debug("translate: Got a filename");
+ $args = { filename => $_[0] };
+ }
+ else {
+ # We're not impressed. Take your empty string and leave.
+ return "";
+ }
}
else {
- 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 );
+ # You must pass in a hash, or you get nothing.
+ return "" if @_ % 2;
+ $args = { @_ };
}
- if ( exists $producers{ $to } ) {
- $self->{'to'} = $to;
- warn "Using producer '$to.'\n" if $verbose;
+ if ((defined $args->{'filename'} || defined $args->{'file'}) &&
+ not $args->{'data'}) {
+ local *FH;
+ local $/;
+
+ open FH, $args->{'filename'}
+ or die "Can't open $args->{'filename'} for reading: $!";
+ $args->{'data'} = <FH>;
+ close FH or die "Can't close $args->{'filename'}: $!";
}
- 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 );
+
+ #
+ # 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;
}
#
projects / dbsrgits/SQL-Translator.git / commitdiff