Add required database and origin filtering for logical messages.

Logical messages, added in 3fe3511d05, during decoding failed to filter
messages emitted in other databases and messages emitted "under" a
replication origin the output plugin isn't interested in.

Add tests to verify that both types of filtering actually work. While
touching message.sql remove hunk obsoleted by d25379e.

Bump XLOG_PAGE_MAGIC because xl_logical_message changed and because
3fe3511d05 had omitted doing so. 3fe3511d05 additionally didn't bump
catversion, but 7a542700d has done so since.

Author: Petr Jelinek
Reported-By: Andres Freund
Discussion: 20160406142513.wotqy3ba3kanr423@alap3.anarazel.de

contrib/test_decoding/expected/messages.out

@@ -1,6 +1,5 @@
 -- predictability
 SET synchronous_commit = on;
-SET client_encoding = 'utf8';
 SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot', 'test_decoding');
  ?column? 
 ----------
@@ -71,9 +70,30 @@ SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'for
  message: transactional: 1 prefix: test, sz: 11 content:czechtastic
 (7 rows)
 
-SELECT 'init' FROM pg_drop_replication_slot('regression_slot');
+-- test db filtering
+\set prevdb :DBNAME
+\c template1
+SELECT 'otherdb1' FROM pg_logical_emit_message(false, 'test', 'otherdb1');
  ?column? 
 ----------
- init
+ otherdb1
+(1 row)
+
+SELECT 'otherdb2' FROM pg_logical_emit_message(true, 'test', 'otherdb2');
+ ?column? 
+----------
+ otherdb2
+(1 row)
+
+\c :prevdb
+SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'force-binary', '0', 'skip-empty-xacts', '1');
+ data 
+------
+(0 rows)
+
+SELECT 'cleanup' FROM pg_drop_replication_slot('regression_slot');
+ ?column? 
+----------
+ cleanup
 (1 row)
 

contrib/test_decoding/expected/replorigin.out

@@ -59,6 +59,12 @@ SELECT pg_replication_origin_session_setup('test_decoding: regression_slot');
 -- ensure we prevent duplicate setup
 SELECT pg_replication_origin_session_setup('test_decoding: regression_slot');
 ERROR:  cannot setup replication origin when one is already setup
+SELECT '' FROM pg_logical_emit_message(false, 'test', 'this message will not be decoded');
+ ?column? 
+----------
+ 
+(1 row)
+
 BEGIN;
 -- setup transaction origin
 SELECT pg_replication_origin_xact_setup('0/aabbccdd', '2013-01-01 00:00');

contrib/test_decoding/sql/messages.sql

@@ -1,6 +1,5 @@
 -- predictability
 SET synchronous_commit = on;
-SET client_encoding = 'utf8';
 
 SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot', 'test_decoding');
 
@@ -22,4 +21,14 @@ SELECT 'ignorethis' FROM pg_logical_emit_message(true, 'test', 'czechtastic');
 
 SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'force-binary', '0', 'skip-empty-xacts', '1');
 
-SELECT 'init' FROM pg_drop_replication_slot('regression_slot');
+-- test db filtering
+\set prevdb :DBNAME
+\c template1
+
+SELECT 'otherdb1' FROM pg_logical_emit_message(false, 'test', 'otherdb1');
+SELECT 'otherdb2' FROM pg_logical_emit_message(true, 'test', 'otherdb2');
+
+\c :prevdb
+SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'force-binary', '0', 'skip-empty-xacts', '1');
+
+SELECT 'cleanup' FROM pg_drop_replication_slot('regression_slot');

contrib/test_decoding/sql/replorigin.sql

@@ -31,6 +31,8 @@ SELECT pg_replication_origin_session_setup('test_decoding: regression_slot');
 -- ensure we prevent duplicate setup
 SELECT pg_replication_origin_session_setup('test_decoding: regression_slot');
 
+SELECT '' FROM pg_logical_emit_message(false, 'test', 'this message will not be decoded');
+
 BEGIN;
 -- setup transaction origin
 SELECT pg_replication_origin_xact_setup('0/aabbccdd', '2013-01-01 00:00');