Developers of Sympa

[IKEDA Soji <address@concealed>]

Developers,

I examine not to provide connection pooling and auto reconnect of
SDM, but I found it is very costy.  So I restored that feature.

SDM module is now identical to that of sympa-6.2-branch-old.

I dump up the version to 6.2b.1.  Hard tests are appreciated.

Regards,

--- Soji

On Thu,  6 Mar 2014 10:40:24 +0100 (CET)
address@concealed wrote:

> sympa[10373] branches/sympa-6.2-branch/src/lib: [bug] sympa.pl and other 
> daemons crash when database access is gone, instead of keeping retry.
> Revision 10373 Author sikeda Date 2014-03-06 10:40:24 +0100 (jeu. 06 mars 
> 2014)
> Log Message[bug] sympa.pl and other daemons crash when database access is 
> gone, instead of keeping retry.
> 
> Now SDM::check_db_connect() keeps retry unless 'just_try' option is given.  
> As a result, when db connection is gone (or not available):
> - SDM::db_get_handler() returns immediately.
> - SDM::probe_db(), SDM::quote(), SDM::do_prepared_query() and 
> SDM::do_query() stall while connection is restored.
> 
> Note:
> - SDM::check_db_connect() should be used instead of 
> SDM::connect_sympa_database() to wait for connection safely.
> - SDM::db_get_handler() is not recommented.  DB handler should not be used 
> directly.
> Modified Paths
> branches/sympa-6.2-branch/src/lib/Log.pm
> branches/sympa-6.2-branch/src/lib/SDM.pm
> Diff
> Modified: branches/sympa-6.2-branch/src/lib/Log.pm (10372 => 10373)
> --- branches/sympa-6.2-branch/src/lib/Log.pm  2014-03-06 09:06:46 UTC (rev 
> 10372)
> +++ branches/sympa-6.2-branch/src/lib/Log.pm  2014-03-06 09:40:24 UTC (rev 
> 10373)
> @@ -391,8 +391,6 @@
>  
>  # Scan log_table with appropriate select 
>  sub get_first_db_log {
> -    my $dbh = &SDM::db_get_handler();
> -
>      my $select = shift;
>  
>      my %action_type = ('message' => 
> ['reject','distribute','arc_delete','arc_download',
>  Modified: branches/sympa-6.2-branch/src/lib/SDM.pm (10372 => 10373)
> --- branches/sympa-6.2-branch/src/lib/SDM.pm  2014-03-06 09:06:46 UTC (rev 
> 10372)
> +++ branches/sympa-6.2-branch/src/lib/SDM.pm  2014-03-06 09:40:24 UTC (rev 
> 10373)
> @@ -67,8 +67,14 @@
>      my @params = @_;
>      my $sth;
>  
> -    unless ($sth = $db_source->do_query($query,@params)) {
> -     &Log::do_log('err','SQL query failed to execute in the Sympa 
> database');
> +    if (check_db_connect()) {
> +     unless ($sth = $db_source->do_query($query, @params)) {
> +         Log::do_log('err',
> +             'SQL query failed to execute in the Sympa database');
> +         return undef;
> +     }
> +    } else {
> +     Log::do_log('err', 'Unable to get a handle to Sympa database');
>       return undef;
>      }
>  
> @@ -80,39 +86,52 @@
>      my @params = @_;
>      my $sth;
>  
> -    unless ($sth = $db_source->do_prepared_query($query,@params)) {
> -     &Log::do_log('err','SQL query failed to execute in the Sympa 
> database');
> +    if (check_db_connect()) {
> +     unless ($sth = $db_source->do_prepared_query($query, @params)) {
> +         Log::do_log('err',
> +             'SQL query failed to execute in the Sympa database');
> +         return undef;
> +     }
> +    } else {
> +     Log::do_log('err', 'Unable to get a handle to Sympa database');
>       return undef;
>      }
> -
> +    
>      return $sth;
>  }
>  
>  ## Get database handler
> +## Note: if database connection is not available, this function returns
> +## immediately.
> +##
> +## NOT RECOMMENDED.  Should not access to database handler.
>  sub db_get_handler {
> -    &Log::do_log('debug3', 'Returning handle to sympa database');
> +    Log::do_log('debug3', '()');
>  
> -    if(&check_db_connect()) {
> +    if (check_db_connect('just_try')) {
>       return $db_source->{'dbh'};
> -    }else {
> -     &Log::do_log('err', 'Unable to get a handle to Sympa database');
> +    } else {
> +     Log::do_log('err', 'Unable to get a handle to Sympa database');
>       return undef;
>      }
>  }
>  
>  ## Just check if DB connection is ok
> +## Possible option is 'just_try', won't try to reconnect if database
> +## connection is not available.
>  sub check_db_connect {
> +    my @options = @_;
>      
> -    #&Log::do_log('debug2', 'Checking connection to the Sympa database');
>      ## Is the Database defined
>      unless (&Conf::get_robot_conf('*','db_name')) {
> -     &Log::do_log('err', 'No db_name defined in configuration file');
> +     Log::do_log('err', 'No db_name defined in configuration file');
>       return undef;
>      }
>      
> -    unless ($db_source->{'dbh'} && $db_source->{'dbh'}->ping()) {
> -     unless (&connect_sympa_database('just_try')) {
> -         &Log::do_log('err', 'Failed to connect to database');          
> +    unless ($db_source and $db_source->{'dbh'} and
> +        $db_source->{'dbh'}->ping()) {
> +     unless (connect_sympa_database(@options)) {
> +         Log::do_log('err', 'Failed to connect to database');           
>           return undef;
>       }
>      }
> @@ -122,10 +141,9 @@
>  
>  ## Connect to Database
>  sub connect_sympa_database {
> -    my $option = shift;
> +    Log::do_log('debug2', '(%s)', @_);
> +    my $option = shift || '';
>  
> -    &Log::do_log('debug', 'Connecting to Sympa database');
> -
>      ## We keep trying to connect if this is the first attempt
>      ## Unless in a web context, because we can't afford long response time 
> on the web interface
>      my $db_conf = &Conf::get_parameters_group('*','Database related');
> @@ -161,10 +179,15 @@
>  }
>  
>  sub probe_db {
> -    &Log::do_log('debug3', 'Checking database structure');    
> +    Log::do_log('debug3', 'Checking database structure');    
>      my (%checked, $table);
>      
> -    my $dbh = &db_get_handler();
> +    unless (check_db_connect()) {
> +        Log::do_log('err',
> +            'Could not check the database structure.  Make sure that 
> database connection is available'
> +        );
> +        return undef;
> +    }
>  
>      ## Database structure
>      ## Report changes to listmaster
> @@ -257,7 +280,9 @@
>      $List::use_db = 1;
>  
>      ## Notify listmaster
> -    &List::send_notify_to_listmaster('db_struct_updated',  
> &Conf::get_robot_conf('*','domain'), {'report' => \@report}) if ($#report 
> >= 0);
> +    List::send_notify_to_listmaster('db_struct_updated',
> +        Conf::get_robot_conf('*','domain'), {'report' => \@report})
> +        if @report;
>  
>      return 1;
>  }


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