| Subject: | PATCH: Allow pg_server_prepare with AutoInactiveDestroy |
The attached patch allows for DBD::Pg to specify pg_server_prepare and
AutoInactiveDestroy. Without this patch, DBD::Pg dies with a message
indicating that "ERROR: prepared statement "$statement_id" does not
exist" after any fork if AutoInactiveDestroy is set. Test coverage
proving patch works is included.
| Subject: | dbdpg_auto_inactive_destroy.patch |
diff -Naur old/dbdimp.c new/dbdimp.c
--- old/dbdimp.c 2011-05-10 01:42:15.000000000 +1000
+++ new/dbdimp.c 2011-06-17 20:32:56.000000000 +1000
@@ -3664,6 +3664,16 @@
if (NULL == imp_sth->seg) /* Already been destroyed! */
croak("dbd_st_destroy called twice!");
+ /* If the AutoInactiveDestroy flag has been set, we go no further */
+ if (DBIc_AIADESTROY(imp_dbh)) {
+ if (TRACE4) {
+ TRC(DBILOGFP, "%sskipping sth destroy due to AutoInactiveDestroy\n", THEADER);
+ }
+ DBIc_IMPSET_off(imp_sth); /* let DBI know we've done it */
+ if (TEND) TRC(DBILOGFP, "%sEnd dbd_st_destroy (AutoInactiveDestroy set)\n", THEADER);
+ return;
+ }
+
/* If the InactiveDestroy flag has been set, we go no further */
if (DBIc_IADESTROY(imp_dbh)) {
if (TRACE4) {
diff -Naur old/Makefile.PL new/Makefile.PL
--- old/Makefile.PL 2011-05-10 01:53:37.000000000 +1000
+++ new/Makefile.PL 2011-06-17 20:32:56.000000000 +1000
@@ -203,7 +203,7 @@
ABSTRACT => 'PostgreSQL database driver for the DBI module',
PREREQ_PM => {
'ExtUtils::MakeMaker' => '6.11',
- 'DBI' => '1.52',
+ 'DBI' => '1.614',
'Test::More' => '0.61',
'version' => '0',
},
diff -Naur old/Pg.pm new/Pg.pm
--- old/Pg.pm 2011-05-10 01:53:37.000000000 +1000
+++ new/Pg.pm 2011-06-17 20:32:56.000000000 +1000
@@ -2196,6 +2196,13 @@
rewrite your application not to use use forking. See the section on L</Asynchronous Queries>
for a way to have your script continue to work while the database is processing a request.
+=head3 B<AutoInactiveDestroy> (boolean)
+
+The InactiveDestroy attribute, described above, needs to be explicitly set in the child
+process after a fork. If the code that performs the fork is in a third party module such
+as Sys::Syslog, this can present a problem. Use AutoInactiveDestroy to get around this
+problem.
+
=head3 B<RaiseError> (boolean, inherited)
Forces errors to always raise an exception. Although it defaults to off, it is recommended that this
diff -Naur old/t/02attribs.t new/t/02attribs.t
--- old/t/02attribs.t 2011-02-25 12:12:14.000000000 +1100
+++ new/t/02attribs.t 2011-06-17 20:33:39.000000000 +1000
@@ -18,7 +18,7 @@
if (! $dbh) {
plan skip_all => 'Connection to database failed, cannot continue testing';
}
-plan tests => 249;
+plan tests => 260;
isnt ($dbh, undef, 'Connect to database for handle attributes testing');
@@ -101,6 +101,7 @@
a Profile (not tested)
a ReadOnly
+d AutoInactiveDestroy (must be the last one tested)
d InactiveDestroy (must be the last one tested)
};
@@ -1539,6 +1540,79 @@
is ($attrib, '', $t);
SKIP: {
+ skip ('Cannot test database handle "AutoInactiveDestroy" on a non-forking system', 8)
+ if $^O =~ /Win/;
+
+ require Test::Simple;
+
+ skip ('Test::Simple version 0.47 or better required for testing of attribute "AutoInactiveDestroy"', 8)
+ if $Test::Simple::VERSION < 0.47;
+
+ # Test of forking. Hang on to your hats
+
+ my $answer = 42;
+ $SQL = "SELECT $answer FROM dbd_pg_test WHERE id > ? LIMIT 1";
+
+ for my $destroy (0,1) {
+
+ $dbh = connect_database({nosetup => 1, AutoCommit => 1 });
+ $dbh->{'AutoInactiveDestroy'} = $destroy;
+ $dbh->{'pg_server_prepare'} = 1;
+ $sth = $dbh->prepare($SQL);
+ $sth->execute(1);
+ $sth->finish();
+
+ # Desired flow: parent test, child test, child kill, parent test
+
+ if (fork) {
+ $t=qq{Parent in fork test is working properly ("AutoInactiveDestroy" = $destroy)};
+ $sth->execute(1);
+ $val = $sth->fetchall_arrayref()->[0][0];
+ is ($val, $answer, $t);
+ # Let the child exit first
+ select(undef,undef,undef,0.3);
+ }
+ else { # Child
+ select(undef,undef,undef,0.1); # Age before beauty
+ exit; ## Calls disconnect via DESTROY unless AutoInactiveDestroy set
+ }
+
+ if ($destroy) {
+ $t=qq{Ping works after the child has exited ("AutoInactiveDestroy" = $destroy)};
+ ok ($dbh->ping(), $t);
+
+ $t='Successful ping returns a SQLSTATE code of 00000 (empty string)';
+ my $state = $dbh->state();
+ is ($state, '', $t);
+
+ $t='Statement handle works after forking';
+ $sth->execute(1);
+ $val = $sth->fetchall_arrayref()->[0][0];
+ is ($val, $answer, $t);
+ }
+ else {
+ $t=qq{Ping fails after the child has exited ("AutoInactiveDestroy" = $destroy)};
+ is ( $dbh->ping(), 0, $t);
+
+ $t='Failed ping returns a SQLSTATE code of 08000';
+ my $state = $dbh->state();
+ is ($state, '08000', $t);
+
+ $t=qq{pg_ping gives an error code of -2 after the child has exited ("AutoInactiveDestroy" = $destroy)};
+ is ( $dbh->pg_ping(), -2,$t);
+ ok ($dbh->disconnect(), 'Disconnect from database');
+ }
+ }
+}
+
+# Disconnect in preparation for the fork tests
+ok ($dbh->disconnect(), 'Disconnect from database');
+
+$t='Database handle attribute "Active" is false after disconnect';
+$attrib = $dbh->{Active};
+is ($attrib, '', $t);
+
+SKIP: {
skip ('Cannot test database handle "InactiveDestroy" on a non-forking system', 8)
if $^O =~ /Win/;