1 package SQL::Translator::Utils;
3 # ----------------------------------------------------------------------
5 # ----------------------------------------------------------------------
6 # Copyright (C) 2002-2009 SQLFairy Authors
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; version 2.
12 # This program is distributed in the hope that it will be useful, but
13 # WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 # General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program; if not, write to the Free Software
19 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
21 # -------------------------------------------------------------------
24 use base qw(Exporter);
25 use vars qw($VERSION $DEFAULT_COMMENT @EXPORT_OK);
27 use Digest::SHA1 qw( sha1_hex );
32 $DEFAULT_COMMENT = '-- ';
34 debug normalize_name header_comment parse_list_arg truncate_id_uniquely $DEFAULT_COMMENT parse_mysql_version
37 # ----------------------------------------------------------------------
40 # Will send debugging messages to STDERR, if the caller's $DEBUG global
43 # This debug() function has a neat feature: Occurances of the strings
44 # PKG, LINE, and SUB in each message will be replaced with elements
47 # debug("PKG: Bad things happened on line LINE!");
51 # [SQL::Translator: Bad things happened on line 643]
53 # If called from Translator.pm, on line 643.
54 # ----------------------------------------------------------------------
56 my ($pkg, $file, $line, $sub) = caller(0);
59 return unless ${"$pkg\::DEBUG"};
67 $x =~ s/\bPKG\b/$pkg/g;
68 $x =~ s/\bLINE\b/$line/g;
69 $x =~ s/\bSUB\b/$sub/g;
70 #warn '[' . $x . "]\n";
71 print STDERR '[' . $x . "]\n";
75 # ----------------------------------------------------------------------
77 my $name = shift or return '';
79 # The name can only begin with a-zA-Z_; if there's anything
81 $name =~ s/^([^a-zA-Z_])/_$1/;
83 # anything other than a-zA-Z0-9_ in the non-first position
84 # needs to be turned into _
85 $name =~ tr/[a-zA-Z0-9_]/_/c;
87 # All duplicated _ need to be squashed into one.
96 # ----------------------------------------------------------------------
98 my $producer = shift || caller;
99 my $comment_char = shift;
100 my $now = scalar localtime;
102 $comment_char = $DEFAULT_COMMENT
103 unless defined $comment_char;
105 my $header_comment =<<"HEADER_COMMENT";
107 ${comment_char}Created by $producer
108 ${comment_char}Created on $now
112 # Any additional stuff passed in
113 for my $additional_comment (@_) {
114 $header_comment .= "${comment_char}${additional_comment}\n";
117 return $header_comment;
120 # ----------------------------------------------------------------------
123 # Meant to accept a list, an array reference, or a string of
124 # comma-separated values. Retuns an array reference of the
125 # arguments. Modified to also handle a list of references.
126 # ----------------------------------------------------------------------
128 my $list = UNIVERSAL::isa( $_[0], 'ARRAY' ) ? shift : [ @_ ];
131 # This protects stringification of references.
133 if ( @$list && ref $list->[0] ) {
137 # This processes string-like arguments.
141 map { s/^\s+|\s+$//g; $_ }
143 grep { defined && length } @$list
148 # ----------------------------------------------------------------------
149 # truncate_id_uniquely( $desired_name, $max_symbol_length )
151 # Truncates the name $desired_name to the $max_symbol_length by
152 # including part of the hash of the full name at the end of the
153 # truncated name, giving a high probability that the symbol will be
155 # ----------------------------------------------------------------------
156 my $COLLISION_TAG_LENGTH = 8;
157 sub truncate_id_uniquely {
158 my ( $desired_name, $max_symbol_length ) = @_;
160 return $desired_name unless defined $desired_name && length $desired_name > $max_symbol_length;
162 my $truncated_name = substr $desired_name, 0, $max_symbol_length - $COLLISION_TAG_LENGTH - 1;
164 # Hex isn't the most space-efficient, but it skirts around allowed
166 my $digest = sha1_hex($desired_name);
167 my $collision_tag = substr $digest, 0, $COLLISION_TAG_LENGTH;
169 return $truncated_name
175 #---------------------------------------------------------------------
176 # parse_mysql_version ( $version_string, $result_target)
178 # Attempts to parse an arbitrary string as a mysql version number.
179 # Returns either a floating point perl style string, or a mysql style
180 # 5 digit string, depending on the supplied $result_target
181 #---------------------------------------------------------------------
182 sub parse_mysql_version {
183 my ($v, $target) = @_;
185 return undef unless $v;
192 if ( $v =~ / ^ (\d+) \. (\d{1,3}) (?: \. (\d{1,3}) )? $ /x ) {
193 push @vers, $1, $2, $3;
196 # XYYZZ (mysql) style
197 elsif ( $v =~ / ^ (\d) (\d{2}) (\d{2}) $ /x ) {
198 push @vers, $1, $2, $3;
201 # XX.YYYZZZ (perl) style or simply X
202 elsif ( $v =~ / ^ (\d+) (?: \. (\d{3}) (\d{3}) )? $ /x ) {
203 push @vers, $1, $2, $3;
206 #how do I croak sanely here?
207 die "Unparseable MySQL version '$v'";
210 if ($target eq 'perl') {
211 return sprintf ('%d.%03d%03d', map { $_ || 0 } (@vers) );
213 elsif ($target eq 'mysql') {
214 return sprintf ('%d%02d%02d', map { $_ || 0 } (@vers) );
217 #how do I croak sanely here?
218 die "Unknown version target '$target'";
225 # ----------------------------------------------------------------------
231 SQL::Translator::Utils - SQL::Translator Utility functions
235 use SQL::Translator::Utils qw(debug);
236 debug("PKG: Bad things happened");
240 C<SQL::Translator::Utils> contains utility functions designed to be
241 used from the other modules within the C<SQL::Translator> modules.
243 Nothing is exported by default.
245 =head1 EXPORTED FUNCTIONS AND CONSTANTS
249 C<debug> takes 0 or more messages, which will be sent to STDERR using
250 C<warn>. Occurances of the strings I<PKG>, I<SUB>, and I<LINE>
251 will be replaced by the calling package, subroutine, and line number,
252 respectively, as reported by C<caller(1)>.
254 For example, from within C<foo> in F<SQL/Translator.pm>, at line 666:
256 debug("PKG: Error reading file at SUB/LINE");
260 [SQL::Translator: Error reading file at foo/666]
262 The entire message is enclosed within C<[> and C<]> for visual clarity
263 when STDERR is intermixed with STDOUT.
265 =head2 normalize_name
267 C<normalize_name> takes a string and ensures that it is suitable for
268 use as an identifier. This means: ensure that it starts with a letter
269 or underscore, and that the rest of the string consists of only
270 letters, numbers, and underscores. A string that begins with
271 something other than [a-zA-Z] will be prefixer with an underscore, and
272 all other characters in the string will be replaced with underscores.
273 Finally, a trailing underscore will be removed, because that's ugly.
275 normalize_name("Hello, world");
281 A more useful example, from the C<SQL::Translator::Parser::Excel> test
284 normalize_name("silly field (with random characters)");
288 silly_field_with_random_characters
290 =head2 header_comment
292 Create the header comment. Takes 1 mandatory argument (the producer
293 classname), an optional comment character (defaults to $DEFAULT_COMMENT),
294 and 0 or more additional comments, which will be appended to the header,
295 prefixed with the comment character. If additional comments are provided,
296 then a comment string must be provided ($DEFAULT_COMMENT is exported for
297 this use). For example, this:
299 package My::Producer;
301 use SQL::Translator::Utils qw(header_comment $DEFAULT_COMMENT);
303 print header_comment(__PACKAGE__,
310 -- Created by My::Prodcuer
311 -- Created on Fri Apr 25 06:56:02 2003
316 Note the gratuitous spacing.
318 =head2 parse_list_arg
320 Takes a string, list or arrayref (all of which could contain
321 comma-separated values) and returns an array reference of the values.
322 All of the following will return equivalent values:
324 parse_list_arg('id');
325 parse_list_arg('id', 'name');
326 parse_list_arg( 'id, name' );
327 parse_list_arg( [ 'id', 'name' ] );
328 parse_list_arg( qw[ id name ] );
330 =head2 truncate_id_uniquely
332 Takes a string ($desired_name) and int ($max_symbol_length). Truncates
333 $desired_name to $max_symbol_length by including part of the hash of
334 the full name at the end of the truncated name, giving a high
335 probability that the symbol will be unique. For example,
337 truncate_id_uniquely( 'a' x 100, 64 )
338 truncate_id_uniquely( 'a' x 99 . 'b', 64 );
339 truncate_id_uniquely( 'a' x 99, 64 )
341 Will give three different results; specifically:
343 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_7f900025
344 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_6191e39a
345 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_8cd96af2
347 =head2 $DEFAULT_COMMENT
349 This is the default comment string, '-- ' by default. Useful for
352 =head2 parse_mysql_version
354 Used by both L<Parser::MySQL|SQL::Translator::Parser::MySQL> and
355 L<Producer::MySQL|SQL::Translator::Producer::MySQL> in order to provide a
356 consistent format for both C<< parser_args->{mysql_parser_version} >> and
357 C<< producer_args->{mysql_version} >> respectively. Takes any of the following
358 version specifications:
364 5.001005 (perl style)
369 Darren Chamberlain E<lt>darren@cpan.orgE<gt>,
370 Ken Y. Clark E<lt>kclark@cpan.orgE<gt>.