Database management changes

* Added in-base logging through a foreign data wrapper, which is only
possible using PostgreSQL 9.1
* Renamed database-related configuration files to indicate that they are
samples, and added the "real" names to the Git ignore list. Server
distribution modified accordingly.
* Removed PL/PgSQL registration (it was only necessary on 8.4)
* Added pgTAP SQL definitions and a script which will (hopefully) be
executed by the build system after the main Java build in order to
execute database unit tests. The script supports both admin- and user-
level testing. I also added a few tests to make sure the testing framework
actually runs them.
* Added documentation about the database definitions structure

legacyworlds-server-data/db-structure/database.sql

@@ -12,7 +12,9 @@
 -- Read configuration from file
 \set pgadmin `grep ^admin= db-config.txt | sed -e s/.*=//`
 \set dbname `grep ^db= db-config.txt | sed -e s/.*=//`
+\set dbname_string '''':dbname''''
 \set dbuser `grep ^user= db-config.txt | sed -e s/.*=//`
+\set dbuser_string '''':dbuser''''
 \set dbupass ''''`grep ^password= db-config.txt | sed -e s/.*=// -e "s/'/''/g"`''''
 
 
@@ -34,8 +36,21 @@ GRANT CONNECT ON DATABASE :dbname TO :dbuser;
 -- Connect to the LW database with the PostgreSQL admin user
 \c :dbname :pgadmin
 
--- Register PL/PgSQL
-CREATE TRUSTED PROCEDURAL LANGUAGE plpgsql;
+-- Register the dblink extension
+CREATE EXTENSION dblink;
+
+-- Create foreign data wrapper and server used to write logs from within
+-- transanctions
+CREATE FOREIGN DATA WRAPPER pgsql
+	VALIDATOR postgresql_fdw_validator;
+CREATE SERVER srv_logging
+	FOREIGN DATA WRAPPER pgsql
+	OPTIONS ( hostaddr '127.0.0.1' , dbname :dbname_string );
+CREATE USER MAPPING FOR :dbuser
+	SERVER srv_logging
+	OPTIONS ( user :dbuser_string , password :dbupass );
+GRANT USAGE ON FOREIGN SERVER srv_logging TO :dbuser;
+
 
 BEGIN;
 

legacyworlds-server-data/db-structure/parts/functions/002-sys-functions.sql

@@ -61,7 +61,7 @@ BEGIN
 	THEN
 		UPDATE sys.ticker SET status = 'RUNNING' , auto_start = NULL
 			WHERE id = task_id;
-		PERFORM sys.write_log( 'Ticker' , 'INFO'::log_level , 'Scheduled task ''' || t_name
+		PERFORM sys.write_sql_log( 'Ticker' , 'INFO'::log_level , 'Scheduled task ''' || t_name
 			|| ''' has been enabled' );
 	END IF;
 END;

legacyworlds-server-data/db-structure/parts/functions/005-logs-functions.sql

@@ -124,6 +124,42 @@ $$ LANGUAGE plpgsql;
 GRANT EXECUTE ON FUNCTION sys.write_log( TEXT , log_level , TEXT ) TO :dbuser;
 
 
+--
+-- Remotely append a system log entry
+--
+-- This function is called from within transactions in order to write to the
+-- system log. Unlike sys.write_log(), entries added through this function
+-- will not be lost if the transaction is rolled back.
+--
+-- Since the function is meant to be called from SQL code, it does not return
+-- anything as the identifier of the new entry is not required.
+--
+-- Parameters:
+--	_component	The component that is appending to the log
+--	_level		The log level
+--	_message	The message to write
+--
+
+CREATE OR REPLACE FUNCTION sys.write_sql_log( _component TEXT , _level log_level , _message TEXT )
+		RETURNS VOID
+		STRICT VOLATILE
+		SECURITY INVOKER
+	AS $write_sql_log$
+BEGIN
+	PERFORM dblink_connect( 'cn_logging' , 'srv_logging' );
+	PERFORM * FROM dblink( 'cn_logging' ,
+		'SELECT * FROM sys.write_log( '
+			|| quote_literal( _component ) || ' , '''
+			|| _level::text || '''::log_level , '
+			|| quote_literal( _message ) || ' )'
+	) AS ( entry_id bigint );
+	PERFORM dblink_disconnect( 'cn_logging' );
+END;
+$write_sql_log$ LANGUAGE plpgsql;
+
+GRANT EXECUTE ON FUNCTION sys.write_sql_log( TEXT , log_level , TEXT ) TO :dbuser;
+
+
 
 --
 -- Append an exception log entry

legacyworlds-server-data/db-structure/parts/functions/070-users-functions.sql

@@ -181,7 +181,7 @@ BEGIN
 	ELSE
 		RAISE EXCEPTION 'Invalid account status % (account #%)' , st , a_id;
 	END IF;
-	PERFORM sys.write_log( 'AccountManagement' , 'ERROR'::log_level , 'Account re-activation mail could not be sent for account #' || a_id || ', deleting validation key' );
+	PERFORM sys.write_sql_log( 'AccountManagement' , 'ERROR'::log_level , 'Account re-activation mail could not be sent for account #' || a_id || ', deleting validation key' );
 END;
 $$ LANGUAGE plpgsql;
 
@@ -470,7 +470,7 @@ BEGIN
 		WHERE a.address = addr
 		FOR UPDATE;
 	IF NOT FOUND THEN
-		PERFORM sys.write_log( 'AccountManagement' , 'WARNING'::log_level , 'account for "'
+		PERFORM sys.write_sql_log( 'AccountManagement' , 'WARNING'::log_level , 'account for "'
 			|| addr || '" not found' );
 		account_error := 1;
 		RETURN;

legacyworlds-server-data/db-structure/parts/functions/140-planets-functions.sql

@@ -990,7 +990,7 @@ DECLARE
 	st_dmg	REAL;
 	n_dest	INT;
 BEGIN
-	PERFORM sys.write_log( 'BattleUpdate' , 'TRACE'::log_level , 'Inflicting ' || dmg
+	PERFORM sys.write_sql_log( 'BattleUpdate' , 'TRACE'::log_level , 'Inflicting ' || dmg
 		|| ' damage to planet #' || p_id );
 
 	bp_id := NULL;
@@ -1008,7 +1008,7 @@ BEGIN
 			st_dmg := 0;
 		END IF;
 		
-		PERFORM sys.write_log( 'BattleUpdate' , 'TRACE'::log_level , 'Building type #' || rec.building_id
+		PERFORM sys.write_sql_log( 'BattleUpdate' , 'TRACE'::log_level , 'Building type #' || rec.building_id
 			|| ' - Damage ' || st_dmg || '; destruction: ' || n_dest );
 
 		-- Apply damage
@@ -1054,7 +1054,7 @@ DECLARE
 BEGIN
 	tick := sys.get_tick( ) - 1;
 	tot_damage := t_upkeep * d_ratio / debt;
-	PERFORM sys.write_log( 'EmpireDebt' , 'DEBUG'::log_level , 'Inflicting debt damage to buildings; total upkeep: '
+	PERFORM sys.write_sql_log( 'EmpireDebt' , 'DEBUG'::log_level , 'Inflicting debt damage to buildings; total upkeep: '
 		|| t_upkeep || ', damage ratio: ' || d_ratio || ', total damage: ' || tot_damage );
 
 	FOR p_rec IN SELECT ep.planet_id AS planet , b.id AS battle

legacyworlds-server-data/db-structure/parts/functions/150-battle-functions.sql

@@ -653,7 +653,7 @@ BEGIN
 	IF NOT att THEN
 		st_power := battles.get_defence_power( b_id , tick );
 		tot_power := tot_power + st_power;
-		PERFORM sys.write_log( 'BattleUpdate' , 'TRACE'::log_level , 'About to inflict planet damage; total power: ' || tot_power
+		PERFORM sys.write_sql_log( 'BattleUpdate' , 'TRACE'::log_level , 'About to inflict planet damage; total power: ' || tot_power
 			|| '; planet power: ' || st_power || '; computed damage: ' || ( dmg * st_power / tot_power )::REAL );
 		IF st_power <> 0 THEN
 			PERFORM verse.inflict_battle_damage( planet , st_power , ( dmg * st_power / tot_power )::REAL , b_id , tick );

legacyworlds-server-data/db-structure/parts/functions/165-fleets-functions.sql

@@ -415,17 +415,17 @@ BEGIN
 			-- Fleet redirection
 			IF rec.is_ref_point IS NULL THEN
 				-- Fleet moving in outer space
-				PERFORM sys.write_log( 'Fleets' , 'TRACE'::log_level , 'About to perform outer space redirect; '
+				PERFORM sys.write_sql_log( 'Fleets' , 'TRACE'::log_level , 'About to perform outer space redirect; '
 					|| 'OOFT/2 = ' || rec.flight_time || '; start(x;y)= (' || rec.os_start_x || ';' || rec.os_start_y
 					|| '); dest(x;y)= (' || rec.x || ';' || rec.y || '); time left: ' || rec.mv_state_time );
 				SELECT INTO cx , cy c_x , c_y FROM fleets.compute_current_location(
 						rec.flight_time , rec.os_start_x , rec.os_start_y , rec.x , rec.y ,
 						rec.mv_state_time );
-				PERFORM sys.write_log( 'Fleets' , 'TRACE'::log_level , 'Computed current coordinates: (' || cx
+				PERFORM sys.write_sql_log( 'Fleets' , 'TRACE'::log_level , 'Computed current coordinates: (' || cx
 					|| ';' || cy || ')' );
 				SELECT INTO dur , s_dur duration , s_duration
 					FROM fleets.compute_outerspace_redirect( rec.flight_time , cx , cy , dest_id );
-				PERFORM sys.write_log( 'Fleets' , 'TRACE'::log_level , 'Computed new total/state duration: '
+				PERFORM sys.write_sql_log( 'Fleets' , 'TRACE'::log_level , 'Computed new total/state duration: '
 					|| dur || ' / ' || s_dur );
 				UPDATE fleets.ms_space SET start_x = cx , start_y = cy
 					WHERE movement_id = rec.id; 
@@ -1000,7 +1000,7 @@ DECLARE
 	found	INT;
 	deleted	INT;
 BEGIN
-	PERFORM sys.write_log( 'BattleUpdate' , 'TRACE'::log_level , 'Inflicting '
+	PERFORM sys.write_sql_log( 'BattleUpdate' , 'TRACE'::log_level , 'Inflicting '
 		|| dmg || ' damage to fleet #' || f_id );
 
 	-- Get total fleet power and battle protagonist
@@ -1094,7 +1094,7 @@ DECLARE
 BEGIN
 	tick := sys.get_tick( ) - 1;
 	tot_damage := t_upkeep * d_ratio / debt;
-	PERFORM sys.write_log( 'EmpireDebt' , 'DEBUG'::log_level , 'Inflicting debt damage to fleets; total upkeep: '
+	PERFORM sys.write_sql_log( 'EmpireDebt' , 'DEBUG'::log_level , 'Inflicting debt damage to fleets; total upkeep: '
 		|| t_upkeep || ', damage ratio: ' || d_ratio || ', total damage: ' || tot_damage );
 
 	FOR f_rec IN SELECT f.id AS fleet , f.status , f.location_id AS location ,

legacyworlds-server-data/db-structure/parts/functions/180-messages-functions.sql

@@ -585,13 +585,13 @@ BEGIN
 	-- Send message (or not)
 	IF do_send
 	THEN
-		PERFORM sys.write_log( 'Messages' , 'DEBUG'::log_level , 'Delivering message from empire #' || e_id
+		PERFORM sys.write_sql_log( 'Messages' , 'DEBUG'::log_level , 'Delivering message from empire #' || e_id
 			|| ' using method ' || s_meth || ' with target identifier ' || tg_id || ' (title text null? '
 			|| ( ttl_txt IS NULL ) || ' ; content text null? ' || (cnt_txt IS NULL) || ')' );
 		EXECUTE 'SELECT msgs.deliver_' || s_meth || '( $1 , $2 , $3 , $4 )'
 			USING e_id , tg_id , ttl_txt , cnt_txt;
 	ELSE
-		PERFORM sys.write_log( 'Messages' , 'DEBUG'::log_level , 'Simulated message delivery from empire #' || e_id
+		PERFORM sys.write_sql_log( 'Messages' , 'DEBUG'::log_level , 'Simulated message delivery from empire #' || e_id
 			|| ' using method ' || s_meth || ' with target identifier ' || tg_id || ' (title text null? '
 			|| ( ttl_txt IS NULL ) || ' ; content text null? ' || (cnt_txt IS NULL) || ')' );
 	END IF;
@@ -860,13 +860,13 @@ BEGIN
 	-- Send message (or not)
 	IF do_send
 	THEN
-		PERFORM sys.write_log( 'Messages' , 'DEBUG'::log_level , 'Delivering message from admin #' || a_id
+		PERFORM sys.write_sql_log( 'Messages' , 'DEBUG'::log_level , 'Delivering message from admin #' || a_id
 			|| ' using method ' || s_meth || ' with target identifier ' || tg_id || ' (title text null? '
 			|| ( ttl_txt IS NULL ) || ' ; content text null? ' || (cnt_txt IS NULL) || ')' );
 		EXECUTE 'SELECT msgs.deliver_admin_' || s_meth || '( $1 , $2 , $3 , $4 )'
 			USING a_id , tg_id , ttl_txt , cnt_txt;
 	ELSE
-		PERFORM sys.write_log( 'Messages' , 'DEBUG'::log_level , 'Simulated message delivery from admin #' || a_id
+		PERFORM sys.write_sql_log( 'Messages' , 'DEBUG'::log_level , 'Simulated message delivery from admin #' || a_id
 			|| ' using method ' || s_meth || ' with target identifier ' || tg_id || ' (title text null? '
 			|| ( ttl_txt IS NULL ) || ' ; content text null? ' || (cnt_txt IS NULL) || ')' );
 	END IF;

legacyworlds-server-data/db-structure/parts/functions/190-admin-functions.sql

@@ -663,7 +663,7 @@ BEGIN
 		INSERT INTO admin.archived_ban_requests ( request_id , credentials_id )
 			VALUES ( b_id , u_id );
 		DELETE FROM admin.active_ban_requests WHERE request_id = b_id;
-		PERFORM sys.write_log( 'Bans' , 'INFO'::log_level , 'Ban request #' || b_id
+		PERFORM sys.write_sql_log( 'Bans' , 'INFO'::log_level , 'Ban request #' || b_id
 			|| ' (user account #' || u_id || ') expired' );
 	END LOOP;
 END;
@@ -707,7 +707,7 @@ BEGIN
 	-- Delete empire and active account record
 	PERFORM emp.delete_empire( e_id );
 	DELETE FROM users.active_accounts WHERE credentials_id = a_id;
-	PERFORM sys.write_log( 'Bans' , 'INFO'::log_level , 'Deleted empire #' || e_id
+	PERFORM sys.write_sql_log( 'Bans' , 'INFO'::log_level , 'Deleted empire #' || e_id
 		|| ' (user account #' || a_id || ')' );
 
 	RETURN TRUE;

legacyworlds-server-data/db-structure/tests/user/priv/sys/logs.sql

@@ -0,0 +1,39 @@
+BEGIN;
+	SELECT plan( 3 );
+
+	--
+	-- Insertion through sys.write_log()
+	--
+	CREATE OR REPLACE FUNCTION _test_this( )
+		RETURNS BIGINT
+	AS $$
+		SELECT sys.write_log( 'test' , 'WARNING'::log_level , 'test' );
+	$$ LANGUAGE SQL;
+	SELECT lives_ok( 'SELECT _test_this()' );
+	DROP FUNCTION _test_this( );
+
+	--
+	-- Direct insertion must fail
+	--
+	CREATE FUNCTION _test_this( )
+		RETURNS VOID
+	AS $$
+		INSERT INTO sys.logs( component , level , message )
+			VALUES ( 'test' , 'WARNING'::log_level , 'test' );
+	$$ LANGUAGE SQL;
+	SELECT throws_ok( 'SELECT _test_this()' , 42501 );
+	DROP FUNCTION _test_this( );
+
+	--
+	-- Updates must fail
+	--
+	CREATE OR REPLACE FUNCTION _test_this( )
+		RETURNS VOID
+	AS $$
+		UPDATE sys.logs SET component = 'random' WHERE component = 'test';
+	$$ LANGUAGE SQL;
+	SELECT throws_ok( 'SELECT _test_this()' , 42501 );
+	DROP FUNCTION _test_this( );
+	
+	SELECT * FROM finish( );
+ROLLBACK;