Bug 302876: Database Version-Checking needs to be more modular and more generic

Patch By Max Kanat-Alexander <mkanat@bugzilla.org> r=wicked, a=myk

4 files changed, 20 insertions, 38 deletions

diff --git a/Bugzilla/Constants.pm b/Bugzilla/Constants.pm
index aed574f67..0c451c8c3 100644
--- a/Bugzilla/Constants.pm
+++ b/Bugzilla/Constants.pm
@@ -101,6 +101,8 @@ use base qw(Exporter);
     FIELD_TYPE_FREETEXT
 
     BUG_STATE_OPEN
+
+    DB_MODULE
 );
 
 @Bugzilla::Constants::EXPORT_OK = qw(contenttypes);
@@ -277,3 +279,13 @@ use constant BUG_STATE_OPEN => ('NEW', 'REOPENED', 'ASSIGNED',
                                 'UNCONFIRMED');
 
 1;
+
+# Data about what we require for different databases.
+use constant DB_MODULE => {
+    'mysql' => {db => 'Bugzilla::DB::Mysql', db_version => '4.0.14',
+                dbd => 'DBD::mysql', dbd_version => '2.9003',
+                name => 'MySQL'},
+    'pg'    => {db => 'Bugzilla::DB::Pg', db_version => '8.00.0000',
+                dbd => 'DBD::Pg', dbd_version => '1.45',
+                name => 'PostgreSQL'},
+};
diff --git a/Bugzilla/DB.pm b/Bugzilla/DB.pm
index 127218843..4a0099db4 100644
--- a/Bugzilla/DB.pm
+++ b/Bugzilla/DB.pm
@@ -48,6 +48,7 @@ use base qw(Exporter DBI::db);
 Exporter::export_ok_tags('deprecated');
 
 use Bugzilla::Config qw(:DEFAULT :db);
+use Bugzilla::Constants;
 use Bugzilla::Util;
 use Bugzilla::Error;
 use Bugzilla::DB::Schema;
@@ -164,14 +165,11 @@ sub connect_main {
 sub _connect {
     my ($driver, $host, $dbname, $port, $sock, $user, $pass) = @_;
 
-    # DB specific module have the same name as DB driver, here we
-    # just make sure we are not case sensitive
-    (my $db_module = $driver) =~ s/(\w+)/\u\L$1/g;
-    my $pkg_module = "Bugzilla::DB::" . $db_module;
+    my $pkg_module = DB_MODULE->{lc($driver)}->{db};
 
     # do the actual import
     eval ("require $pkg_module")
-        || die ("'$db_module' is not a valid choice for \$db_driver in "
+        || die ("'$driver' is not a valid choice for \$db_driver in "
                 . " localconfig: " . $@);
 
     # instantiate the correct DB specific module
@@ -622,8 +620,9 @@ sub bz_rename_column {
 sub _bz_schema {
     my ($self) = @_;
     return $self->{private_bz_schema} if exists $self->{private_bz_schema};
-    $self->{private_bz_schema} = 
-        Bugzilla::DB::Schema->new($self->MODULE_NAME);
+    my @module_parts = split('::', ref $self);
+    my $module_name  = pop @module_parts;
+    $self->{private_bz_schema} = Bugzilla::DB::Schema->new($module_name);
     return $self->{private_bz_schema};
 }
 
@@ -989,28 +988,6 @@ constants are required to be subroutines or "use constant" variables.
 The C<\%attr> argument that must be passed to bind_param in order to 
 correctly escape a C<LONGBLOB> type.
 
-=item C<REQUIRED_VERSION>
-
-This is the minimum required version of the database server that the
-Bugzilla::DB subclass requires. It should be in a format suitable for
-passing to vers_cmp during installation.
-
-=item C<PROGRAM_NAME>
-
-The human-readable name of this database. For example, for MySQL, this
-would be 'MySQL.' You should not depend on this variable to know what
-type of database you are running on; this is intended merely for displaying
-to the admin to let them know what DB they're running.
-
-=item C<MODULE_NAME>
-
-The name of the Bugzilla::DB module that we are. For example, for the MySQL
-Bugzilla::DB module, this would be "Mysql." For PostgreSQL it would be "Pg."
-
-=item C<DBD_VERSION>
-
-The minimum version of the DBD module that we require for this database.
-
 =back
 
 
@@ -1559,4 +1536,6 @@ PopGlobalSQLState
 
 L<DBI>
 
+L<Bugzilla::Constants> - The C<DB_MODULE> constant.
+
 =cut
diff --git a/Bugzilla/DB/Mysql.pm b/Bugzilla/DB/Mysql.pm
index e03fbc910..9493fb099 100644
--- a/Bugzilla/DB/Mysql.pm
+++ b/Bugzilla/DB/Mysql.pm
@@ -49,11 +49,6 @@ use Bugzilla::Error;
 # This module extends the DB interface via inheritance
 use base qw(Bugzilla::DB);
 
-use constant REQUIRED_VERSION => '4.0.14';
-use constant PROGRAM_NAME => 'MySQL';
-use constant MODULE_NAME  => 'Mysql';
-use constant DBD_VERSION  => '2.9003';
-
 sub new {
     my ($class, $user, $pass, $host, $dbname, $port, $sock) = @_;
 
diff --git a/Bugzilla/DB/Pg.pm b/Bugzilla/DB/Pg.pm
index 5162466c5..7bf64ab9d 100644
--- a/Bugzilla/DB/Pg.pm
+++ b/Bugzilla/DB/Pg.pm
@@ -50,10 +50,6 @@ use DBD::Pg;
 use base qw(Bugzilla::DB);
 
 use constant BLOB_TYPE => { pg_type => DBD::Pg::PG_BYTEA };
-use constant REQUIRED_VERSION => '8.00.0000';
-use constant PROGRAM_NAME => 'PostgreSQL';
-use constant MODULE_NAME  => 'Pg';
-use constant DBD_VERSION  => '1.45';
 
 sub new {
     my ($class, $user, $pass, $host, $dbname, $port) = @_;