X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FSQL%2FTranslator.pm;h=96a8d5dd9e78919d0d35dfa7beaec0f743a9534d;hb=841a3f1a241cff7e2f9fbc1bdc1e84aaa0f10909;hp=25b7190d0eab7156407812d2881292dd025b4075;hpb=16dc997057306c2b93d146478b7b20830d3b5d80;p=dbsrgits%2FSQL-Translator.git diff --git a/lib/SQL/Translator.pm b/lib/SQL/Translator.pm index 25b7190..96a8d5d 100644 --- a/lib/SQL/Translator.pm +++ b/lib/SQL/Translator.pm @@ -1,199 +1,1153 @@ package SQL::Translator; -#----------------------------------------------------- -# $Id: Translator.pm,v 1.1.1.1 2002-03-01 02:26:25 kycl4rk Exp $ +# ---------------------------------------------------------------------- +# $Id: Translator.pm,v 1.42 2003-08-21 18:12:56 kycl4rk Exp $ +# ---------------------------------------------------------------------- +# Copyright (C) 2003 Ken Y. Clark , +# darren chamberlain , +# Chris Mungall # -# 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 +# ------------------------------------------------------------------- use strict; -use vars qw( $VERSION ); -$VERSION = (qw$Revision: 1.1.1.1 $)[-1]; +use vars qw( $VERSION $REVISION $DEFAULT_SUB $DEBUG $ERROR ); +use base 'Class::Base'; + +require 5.004; + +$VERSION = '0.02'; +$REVISION = sprintf "%d.%02d", q$Revision: 1.42 $ =~ /(\d+)\.(\d+)/; +$DEBUG = 0 unless defined $DEBUG; +$ERROR = ""; + +use Carp qw(carp); use Data::Dumper; +use Class::Base; +use File::Spec::Functions qw(catfile); +use File::Basename qw(dirname); +use IO::Dir; +use SQL::Translator::Schema; -use SQL::Translator::Parser::MySQL; -use SQL::Translator::Parser::Sybase; -use SQL::Translator::Producer::Oracle; -use SQL::Translator::Producer::XML; +# ---------------------------------------------------------------------- +# 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 { $_[0]->schema } unless defined $DEFAULT_SUB; +# ---------------------------------------------------------------------- +# init([ARGS]) +# The constructor. # -# These are the inputs we can parse. +# 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". # -my %parsers = ( - mysql => 'MySQL', - sybase => 'Sybase', -); +# 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. +# ---------------------------------------------------------------------- +sub init { + my ( $self, $config ) = @_; + # + # 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. + # + $self->parser ($config->{'parser'} || $config->{'from'} || $DEFAULT_SUB); + $self->producer($config->{'producer'} || $config->{'to'} || $DEFAULT_SUB); + + # + # Set up callbacks for formatting of pk,fk,table,package names in producer + # + $self->format_table_name($config->{'format_table_name'}); + $self->format_package_name($config->{'format_package_name'}); + $self->format_fk_name($config->{'format_fk_name'}); + $self->format_pk_name($config->{'format_pk_name'}); + + # + # Set the parser_args and producer_args + # + for my $pargs ( qw[ parser_args producer_args ] ) { + $self->$pargs( $config->{$pargs} ) if defined $config->{ $pargs }; + } + + # + # Set the data source, if 'filename' or 'file' is provided. + # + $config->{'filename'} ||= $config->{'file'} || ""; + $self->filename( $config->{'filename'} ) if $config->{'filename'}; + + # + # Finally, if there is a 'data' parameter, use that in + # preference to filename and file + # + if ( my $data = $config->{'data'} ) { + $self->data( $data ); + } + + # + # Set various other options. + # + $self->{'debug'} = defined $config->{'debug'} ? $config->{'debug'} : $DEBUG; + + $self->add_drop_table( $config->{'add_drop_table'} ); + + $self->no_comments( $config->{'no_comments'} ); + + $self->show_warnings( $config->{'show_warnings'} ); + + $self->trace( $config->{'trace'} ); + + $self->validate( $config->{'validate'} ); + + return $self; +} + +# ---------------------------------------------------------------------- +# add_drop_table([$bool]) +# ---------------------------------------------------------------------- +sub add_drop_table { + my $self = shift; + if ( defined (my $arg = shift) ) { + $self->{'add_drop_table'} = $arg ? 1 : 0; + } + return $self->{'add_drop_table'} || 0; +} + +# ---------------------------------------------------------------------- +# no_comments([$bool]) +# ---------------------------------------------------------------------- +sub no_comments { + my $self = shift; + my $arg = shift; + if ( defined $arg ) { + $self->{'no_comments'} = $arg ? 1 : 0; + } + return $self->{'no_comments'} || 0; +} + +# ---------------------------------------------------------------------- +# producer([$producer_spec]) # -# These are the formats we can produce. +# Get or set the producer for the current translator. +# ---------------------------------------------------------------------- +sub producer { + my $self = shift; + + # 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\n"); + } + + # passed an anonymous subroutine reference + elsif (isa($producer, 'CODE')) { + $self->{'producer'} = $producer; + $self->{'producer_type'} = "CODE"; + $self->debug("Got producer: code ref\n"); + } + + # passed a string containing no "::"; relative package name + else { + $producer =~ s/-/::/g; + 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\n"); + } + + # At this point, $self->{'producer'} contains a subroutine + # reference that is ready to run + + # Anything left? If so, it's producer_args + $self->producer_args(@_) if (@_); + } + + return $self->{'producer'}; +}; + +# ---------------------------------------------------------------------- +# producer_type() # -my %producers = ( - oracle => 'Oracle', - xml => 'XML', -); +# producer_type is an accessor that allows producer subs to get +# information about their origin. This is poptentially important; +# since all producer subs are called as subroutine references, there is +# no way for a producer to find out which package the sub lives in +# originally, for example. +# ---------------------------------------------------------------------- +sub producer_type { $_[0]->{'producer_type'} } -#----------------------------------------------------- -sub new { +# ---------------------------------------------------------------------- +# producer_args([\%args]) # -# Makes a new object. Intentionally made very bare as -# it is used by all subclasses (unless they override, -# of course). +# Arbitrary name => value pairs of paramters can be passed to a +# producer using this method. +# +# If the first argument passed in is undef, then the hash of arguments +# is cleared; all subsequent elements are added to the hash of name, +# value pairs stored as producer_args. +# ---------------------------------------------------------------------- +sub producer_args { + my $self = shift; + return $self->_args("producer", @_); +} + +# ---------------------------------------------------------------------- +# parser([$parser_spec]) +# ---------------------------------------------------------------------- +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\n"); + } + + # passed an anonymous subroutine reference + elsif ( isa( $parser, 'CODE' ) ) { + $self->{'parser'} = $parser; + $self->{'parser_type'} = "CODE"; + $self->debug("Got parser: code ref\n"); + } + + # passed a string containing no "::"; relative package name + else { + $parser =~ s/-/::/g; + my $Pp = "SQL::Translator::Parser::$parser"; + load( $Pp ) or die "Can't load $Pp: $@"; + $self->{'parser'} = \&{ "$Pp\::parse" }; + $self->{'parser_type'} = $Pp; + $self->debug("Got parser: $Pp\n"); + } + + # + # At this point, $self->{'parser'} contains a subroutine + # reference that is ready to run + # + $self->parser_args( @_ ) if (@_); + } + + return $self->{'parser'}; +} + +# ---------------------------------------------------------------------- +sub parser_type { $_[0]->{'parser_type'} } + +sub parser_args { + my $self = shift; + return $self->_args("parser", @_); +} + +sub show_warnings { + my $self = shift; + my $arg = shift; + if ( defined $arg ) { + $self->{'show_warnings'} = $arg ? 1 : 0; + } + return $self->{'show_warnings'} || 0; +} + + +# filename - get or set the filename +sub filename { + my $self = shift; + if (@_) { + my $filename = shift; + if (-d $filename) { + my $msg = "Cannot use directory '$filename' as input source"; + return $self->error($msg); + } elsif (ref($filename) eq 'ARRAY') { + $self->{'filename'} = $filename; + $self->debug("Got array of files: ".join(', ',@$filename)."\n"); + } elsif (-f _ && -r _) { + $self->{'filename'} = $filename; + $self->debug("Got filename: '$self->{'filename'}'\n"); + } else { + my $msg = "Cannot use '$filename' as input source: ". + "file does not exist or is not readable."; + return $self->error($msg); + } + } + + $self->{'filename'}; +} + +# ---------------------------------------------------------------------- +# data([$data]) # - my $class = shift; - my %args = @_; - my $self = { %args }; - return bless $self, $class; +# if $self->{'data'} is not set, but $self->{'filename'} is, then +# $self->{'filename'} is opened and read, with the results put into +# $self->{'data'}. +# ---------------------------------------------------------------------- +sub data { + my $self = shift; + + # Set $self->{'data'} based on what was passed in. We will + # accept a number of things; do our best to get it right. + if (@_) { + my $data = shift; + if (isa($data, "SCALAR")) { + $self->{'data'} = $data; + } + else { + if (isa($data, 'ARRAY')) { + $data = join '', @$data; + } + elsif (isa($data, 'GLOB')) { + local $/; + $data = <$data>; + } + elsif (! ref $data && @_) { + $data = join '', $data, @_; + } + $self->{'data'} = \$data; + } + } + + # If we have a filename but no data yet, populate. + if (not $self->{'data'} and my $filename = $self->filename) { + $self->debug("Opening '$filename' to get contents.\n"); + local *FH; + local $/; + my $data; + + my @files = ref($filename) eq 'ARRAY' ? @$filename : ($filename); + + foreach my $file (@files) { + unless (open FH, $file) { + return $self->error("Can't read file '$file': $!"); + } + + $data .= ; + + unless (close FH) { + return $self->error("Can't close file '$file': $!"); + } + } + + $self->{'data'} = \$data; + } + + return $self->{'data'}; } -#----------------------------------------------------- -sub error { +# ---------------------------------------------------------------------- +sub reset { # -# Return the last error. +# Deletes the existing Schema object so that future calls to translate +# don't append to the existing. # - return shift()->{'error'} || ''; + my $self = shift; + $self->{'schema'} = undef; + return 1; } -#----------------------------------------------------- -sub error_out { +# ---------------------------------------------------------------------- +sub schema { # -# Record the error and return undef. +# Returns the SQL::Translator::Schema object # my $self = shift; - if ( my $error = shift ) { - $self->{'error'} = $error; + + unless ( defined $self->{'schema'} ) { + $self->{'schema'} = SQL::Translator::Schema->new; + } + + return $self->{'schema'}; +} + +# ---------------------------------------------------------------------- +sub trace { + my $self = shift; + my $arg = shift; + if ( defined $arg ) { + $self->{'trace'} = $arg ? 1 : 0; } - return; + return $self->{'trace'} || 0; } -#----------------------------------------------------- -sub translate { +# ---------------------------------------------------------------------- +# translate([source], [\%args]) +# +# translate does the actual translation. The main argument is the +# source of the data to be translated, which can be a filename, scalar +# reference, or glob reference. # -# Translates any number of given files. +# Alternatively, translate takes optional arguements, which are passed +# to the appropriate places. Most notable of these arguments are +# parser and producer, which can be used to set the parser and +# producer, respectively. This is the applications last chance to set +# these. # - 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; +# translate returns a string. +# ---------------------------------------------------------------------- +sub translate { + my $self = shift; + my ($args, $parser, $parser_type, $producer, $producer_type); + my ($parser_output, $producer_output); - if ( exists $parsers{ $from } ) { - $self->{'from'} = $from; - warn "Using parser '$from.'\n" if $verbose; + # Parse arguments + if (@_ == 1) { + # Passed a reference to a hash? + if (isa($_[0], 'HASH')) { + # yep, a hashref + $self->debug("translate: Got a hashref\n"); + $args = $_[0]; + } + + # Passed a GLOB reference, i.e., filehandle + elsif (isa($_[0], 'GLOB')) { + $self->debug("translate: Got a GLOB reference\n"); + $self->data($_[0]); + } + + # Passed a reference to a string containing the data + elsif (isa($_[0], 'SCALAR')) { + # passed a ref to a string + $self->debug("translate: Got a SCALAR reference (string)\n"); + $self->data($_[0]); + } + + # Not a reference; treat it as a filename + elsif (! ref $_[0]) { + # Not a ref, it's a filename + $self->debug("translate: Got a filename\n"); + $self->filename($_[0]); + } + + # Passed something else entirely. + else { + # We're not impressed. Take your empty string and leave. + # return ""; + + # Actually, if data, parser, and producer are set, then we + # can continue. Too bad, because I like my comment + # (above)... + return "" unless ($self->data && + $self->producer && + $self->parser); + } } 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; + # ---------------------------------------------------------------------- + # Can specify the data to be transformed using "filename", "file", + # "data", or "datasource". + # ---------------------------------------------------------------------- + if (my $filename = ($args->{'filename'} || $args->{'file'})) { + $self->filename($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 ); + + if (my $data = ($args->{'data'} || $args->{'datasource'})) { + $self->data($data); } - # - # Slurp the entire text file we're parsing. - # - 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> ); + # ---------------------------------------------------------------- + # Get the data. + # ---------------------------------------------------------------- + my $data = $self->data; + unless (ref($data) eq 'SCALAR' and length $$data) { + return $self->error("Empty data file!"); + } + + # ---------------------------------------------------------------- + # Local reference to the parser subroutine + # ---------------------------------------------------------------- + if ($parser = ($args->{'parser'} || $args->{'from'})) { + $self->parser($parser); + } + $parser = $self->parser; + $parser_type = $self->parser_type; + + # ---------------------------------------------------------------- + # Local reference to the producer subroutine + # ---------------------------------------------------------------- + if ($producer = ($args->{'producer'} || $args->{'to'})) { + $self->producer($producer); + } + $producer = $self->producer; + $producer_type = $self->producer_type; + + # ---------------------------------------------------------------- + # Execute the parser, then execute the producer with that output. + # Allowances are made for each piece to die, or fail to compile, + # since the referenced subroutines could be almost anything. In + # the future, each of these might happen in a Safe environment, + # depending on how paranoid we want to be. + # ---------------------------------------------------------------- + unless ( defined $self->{'schema'} ) { + eval { $parser_output = $parser->($self, $$data) }; + if ($@ || ! $parser_output) { + my $msg = sprintf "translate: Error with parser '%s': %s", + $parser_type, ($@) ? $@ : " no results"; + return $self->error($msg); + } + } + + $self->debug("Schema =\n", Dumper($self->schema), "\n"); + + if ($self->validate) { + my $schema = $self->schema; + return $self->error('Invalid schema') unless $schema->is_valid; } - warn "Data =\n", Dumper( $data ) if $verbose; - my $output = $producer->translate( $data ); + eval { $producer_output = $producer->($self) }; + if ($@ || ! $producer_output) { + my $msg = sprintf "translate: Error with producer '%s': %s", + $producer_type, ($@) ? $@ : " no results"; + return $self->error($msg); + } + + return $producer_output; } -#----------------------------------------------------- -sub parser { +# ---------------------------------------------------------------------- +# list_parsers() +# +# Hacky sort of method to list all available parsers. This has +# several problems: +# +# - Only finds things in the SQL::Translator::Parser namespace +# +# - Only finds things that are located in the same directory +# as SQL::Translator::Parser. Yeck. +# +# This method will fail in several very likely cases: +# +# - Parser modules in different namespaces +# +# - Parser modules in the SQL::Translator::Parser namespace that +# have any XS componenets will be installed in +# arch_lib/SQL/Translator. # -# Figures out which module to load based on the "from" argument +# ---------------------------------------------------------------------- +sub list_parsers { + return shift->_list("parser"); +} + +# ---------------------------------------------------------------------- +# list_producers() # +# See notes for list_parsers(), above; all the problems apply to +# list_producers as well. +# ---------------------------------------------------------------------- +sub list_producers { + return shift->_list("producer"); +} + + +# ====================================================================== +# Private Methods +# ====================================================================== + +# ---------------------------------------------------------------------- +# _args($type, \%args); +# +# Gets or sets ${type}_args. Called by parser_args and producer_args. +# ---------------------------------------------------------------------- +sub _args { my $self = shift; - unless ( $self->{'parser'} ) { - my $parser_module = - 'SQL::Translator::Parser::'.$parsers{ $self->{'from'} }; - $self->{'parser'} = $parser_module->new; + my $type = shift; + $type = "${type}_args" unless $type =~ /_args$/; + + unless (defined $self->{$type} && isa($self->{$type}, 'HASH')) { + $self->{$type} = { }; } - return $self->{'parser'}; + + if (@_) { + # If the first argument is an explicit undef (remember, we + # don't get here unless there is stuff in @_), then we clear + # out the producer_args hash. + if (! defined $_[0]) { + shift @_; + %{$self->{$type}} = (); + } + + my $args = isa($_[0], 'HASH') ? shift : { @_ }; + %{$self->{$type}} = (%{$self->{$type}}, %$args); + } + + $self->{$type}; } -#----------------------------------------------------- -sub producer { -# -# Figures out which module to load based on the "to" argument +# ---------------------------------------------------------------------- +# _list($type) +# ---------------------------------------------------------------------- +sub _list { + my $self = shift; + my $type = shift || return (); + my $uctype = ucfirst lc $type; + my %found; + + load("SQL::Translator::$uctype") or return (); + my $path = catfile "SQL", "Translator", $uctype; + for (@INC) { + my $dir = catfile $_, $path; + $self->debug("_list_${type}s searching $dir\n"); + next unless -d $dir; + + my $dh = IO::Dir->new($dir); + for (grep /\.pm$/, $dh->read) { + s/\.pm$//; + $found{ join "::", "SQL::Translator::$uctype", $_ } = 1; + } + } + + return keys %found; +} + +# ---------------------------------------------------------------------- +# load($module) # +# Loads a Perl module. Short circuits if a module is already loaded. +# ---------------------------------------------------------------------- +sub load { + my $module = do { my $m = shift; $m =~ s[::][/]g; "$m.pm" }; + return 1 if $INC{$module}; + + eval { + require $module; + $module->import(@_); + }; + + return __PACKAGE__->error($@) if ($@); + return 1; +} + +# ---------------------------------------------------------------------- +sub format_table_name { + return shift->_format_name('_format_table_name', @_); +} + +# ---------------------------------------------------------------------- +sub format_package_name { + return shift->_format_name('_format_package_name', @_); +} + +# ---------------------------------------------------------------------- +sub format_fk_name { + return shift->_format_name('_format_fk_name', @_); +} + +# ---------------------------------------------------------------------- +sub format_pk_name { + return shift->_format_name('_format_pk_name', @_); +} + +# ---------------------------------------------------------------------- +# The other format_*_name methods rely on this one. It optionally +# accepts a subroutine ref as the first argument (or uses an identity +# sub if one isn't provided or it doesn't already exist), and applies +# it to the rest of the arguments (if any). +# ---------------------------------------------------------------------- +sub _format_name { my $self = shift; - unless ( $self->{'producer'} ) { - my $from = $parsers{ $self->{'from'} }; - my $producer_module = - 'SQL::Translator::Producer::'.$producers{ $self->{'to'} }; - $self->{'producer'} = $producer_module->new( from => $from ); + my $field = shift; + my @args = @_; + + if (ref($args[0]) eq 'CODE') { + $self->{$field} = shift @args; } - return $self->{'producer'}; + elsif (! exists $self->{$field}) { + $self->{$field} = sub { return shift }; + } + + return @args ? $self->{$field}->(@args) : $self->{$field}; +} + +# ---------------------------------------------------------------------- +# isa($ref, $type) +# +# Calls UNIVERSAL::isa($ref, $type). I think UNIVERSAL::isa is ugly, +# but I like function overhead. +# ---------------------------------------------------------------------- +sub isa($$) { + my ($ref, $type) = @_; + return UNIVERSAL::isa($ref, $type); +} + +# ---------------------------------------------------------------------- +sub validate { + my ( $self, $arg ) = @_; + if ( defined $arg ) { + $self->{'validate'} = $arg ? 1 : 0; + } + return $self->{'validate'} || 0; } 1; -#----------------------------------------------------- -# Rescue the drowning and tie your shoestrings. -# Henry David Thoreau -#----------------------------------------------------- +# ---------------------------------------------------------------------- +# Who killed the pork chops? +# What price bananas? +# Are you my Angel? +# Allen Ginsberg +# ---------------------------------------------------------------------- + +=pod =head1 NAME -SQL::Translator - convert schema from one database to another +SQL::Translator - manipulate structured data definitions (SQL and more) =head1 SYNOPSIS use SQL::Translator; - my $translator = SQL::Translator->new; - my $output = $translator->translate( - from => 'mysql', - to => 'oracle', - file => $file, + + my $translator = SQL::Translator->new( + # Print debug info + debug => 1, + # Print Parse::RecDescent trace + trace => 0, + # Don't include comments in output + no_comments => 0, + # Print name mutations, conflicts + show_warnings => 0, + # Add "drop table" statements + add_drop_table => 1, + # Validate schema object + validate => 1, + # Make all table names CAPS in producers which support this option + format_table_name => sub {my $tablename = shift; return uc($tablename)}, + # Null-op formatting, only here for documentation's sake + format_package_name => sub {return shift}, + format_fk_name => sub {return shift}, + format_pk_name => sub {return shift}, + ); + + my $output = $translator->translate( + from => 'MySQL', + to => 'Oracle', + # Or an arrayref of filenames, i.e. [ $file1, $file2, $file3 ] + 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 could -just write the PostgreSQL parser and use an existing Oracle producer. +SQL::Translator is a group of Perl modules that converts +vendor-specific SQL table definitions into other formats, such as +other vendor-specific SQL, ER diagrams, documentation (POD and HTML), +XML, and Class::DBI classes. The main focus of SQL::Translator is +SQL, but parsers exist for other structured data formats, including +Excel spreadsheets and arbitrarily delimited text files. Through the +separation of the code into parsers and producers with an object model +in between, it's possible to combine any parser with any producer, to +plug in custom parsers or producers, or to manipulate the parsed data +via the built-in object model. Presently only the definition parts of +SQL are handled (CREATE, ALTER), not the manipulation of data (INSERT, +UPDATE, DELETE). -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 CONSTRUCTOR -=head1 AUTHOR +The constructor is called C, and accepts a optional hash of options. +Valid options are: -Ken Y. Clark, kclark@logsoft.com +=over 4 -=head1 SEE ALSO +=item * + +parser / from + +=item * + +parser_args + +=item * + +producer / to + +=item * + +producer_args + +=item * + +filename / file + +=item * + +data + +=item * + +debug + +=item * + +add_drop_table + +=item * + +no_comments + +=item * + +trace + +=item * + +validate + +=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. + +=head1 METHODS + +=head2 add_drop_table + +Toggles whether or not to add "DROP TABLE" statements just before the +create definitions. + +=head2 no_comments + +Toggles whether to print comments in the output. Accepts a true or false +value, returns the current value. + +=head2 producer + +The C 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 (I) +and passed 2 parameters: its container C instance and a +data structure. It is expected that the function transform the data +structure to a string. The C instance is provided for +informational purposes; for example, the type of the parser can be +retrieved using the C method, and the C and +C methods can be called when needed. + +When defining a producer, one of several things can be passed in: A +module name (e.g., C), a module name relative to +the C namespace (e.g., C), a module +name and function combination (C), +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: C<$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 +F, C will attempt +to load F and use C as the name of +the function, instead of the default C. + + 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) + $tr->producer("Sybase"); -perl(1). + # This will invoke My::Groovy::Producer::transmogrify($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); + $tr->producer(\&my_producer); + +There is also a method named C, which is a string +containing the classname to which the above C function +belongs. In the case of anonymous subroutines, this method returns +the string "CODE". + +Finally, there is a method named C, which is both an +accessor and a mutator. Arbitrary data may be stored in name => value +pairs for the producer subroutine to access: + + sub My::Random::producer { + my ($tr, $data) = @_; + my $pr_args = $tr->producer_args(); + + # $pr_args is a hashref. + +Extra data passed to the C method is passed to +C: + + $tr->producer("xSV", delimiter => ',\s*'); + + # In SQL::Translator::Producer::xSV: + my $args = $tr->producer_args; + my $delimiter = $args->{'delimiter'}; # value is ,\s* + +=head2 parser + +The C method defines or retrieves a subroutine that will be +called to perform the parsing. The basic idea is the same as that of +C (see above), except the default subroutine name is +"parse", and will be invoked as C<$module_name::parse($tr, $data)>. +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([ $_[1] ], [ "SQL" ]); + $dumper->Purity(1)->Terse(1)->Deepcopy(1); + return $dumper->Dump; + }); + +There is also C and C, which perform +analogously to C and C + +=head2 show_warnings + +Toggles whether to print warnings of name conflicts, identifier +mutations, etc. Probably only generated by producers to let the user +know when something won't translate very smoothly (e.g., MySQL "enum" +fields into Oracle). Accepts a true or false value, returns the +current value. + +=head2 translate + +The C method calls the subroutines referenced by the +C and C 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 +C and C methods). + +Here is how the parameter list to C is parsed: + +=over + +=item * + +1 argument means it's the data to be parsed; which could be a string +(filename) or a reference 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 + +=head2 filename, data + +Using the C method, the filename of the data to be parsed +can be set. This method can be used in conjunction with the C +method, below. If both the C and C methods are +invoked as mutators, the data set in the C method is used. + + $tr->filename("/my/data/files/create.sql"); + +or: + + my $create_script = do { + local $/; + open CREATE, "/my/data/files/create.sql" or die $!; + ; + }; + $tr->data(\$create_script); + +C takes a string, which is interpreted as a filename. +C takes a reference to a string, which is used as the data to be +parsed. If a filename is set, then that file is opened and read when +the C method is called, as long as the data instance +variable is not set. + +=head2 schema + +Returns the SQL::Translator::Schema object. + +=head2 trace + +Turns on/off the tracing option of Parse::RecDescent. + +=head2 validate + +Whether or not to validate the schema object after parsing and before +producing. + +=head1 AUTHORS + +The following people have contributed to the SQLFairy project: + +=over 4 + +=item * Mark Addison + +=item * Sam Angiuoli + +=item * Darren Chamberlain + +=item * Ken Y. Clark + +=item * Allen Day + +=item * Paul Harrington + +=item * Mikey Melillo + +=item * Chris Mungall + +=item * Ross Smith II + +=item * Gudmundur A. Thorisson + +=item * Chris To + +=item * Jason Williams + +=item * Ying Zhang + +=back + +If you would like to contribute to the project, you can send patches +to the developers mailing list: + + sqlfairy-developers@lists.sourceforge.net + +Or send us a message (with your Sourceforge username) asking to be +added to the project and what you'd like to contribute. + + +=head1 COPYRIGHT + +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 BUGS + +Please use L for reporting bugs. + +=head1 PRAISE + +If you find this module useful, please use +L to rate it. + +=head1 SEE ALSO -=cut +L, +L, +L, +L, +L, +L, +L, +L, +L.