launchpad-reviewers team mailing list archive

[Colin Watson <cjwatson@xxxxxxxxxxxxx>]

Colin Watson has proposed merging lp:~cjwatson/launchpad/postgresql-10-replication into lp:launchpad with lp:~cjwatson/launchpad/postgresql-version-checks as a prerequisite.

Commit message:
Update replication machinery to cope with changes in PostgreSQL 10.

Requested reviews:
  Launchpad code reviewers (launchpad-reviewers)

For more details, see:
https://code.launchpad.net/~cjwatson/launchpad/postgresql-10-replication/+merge/363972

I don't have a setup that allows me to test any of this at the moment, so I'm flying somewhat blind.

I've left the 9.3/xlog reference in database/replication/Makefile alone.  Precedent seems to be that we just update that once staging has been upgraded.
-- 
Your team Launchpad code reviewers is requested to review the proposed merge of lp:~cjwatson/launchpad/postgresql-10-replication into lp:launchpad.

=== modified file 'database/replication/walblock.py'
--- database/replication/walblock.py	2014-01-13 07:38:24 +0000
+++ database/replication/walblock.py	2019-03-05 13:35:13 +0000
@@ -22,8 +22,8 @@
         help="Block if there are more than N unshipped WAL files.", default=25)
     parser.add_option(
         "-d", dest="wal_dir", metavar="DIR", type="string",
-        help="Path to pg_xlog directory",
-        default="/var/lib/postgresql/9.1/main/pg_xlog")
+        help="Path to pg_wal directory",
+        default="/var/lib/postgresql/10/main/pg_wal")
     parser.add_option(
         "-v", "--verbose", action="store_true", default=False, help="Verbose")
     options, args = parser.parse_args()

=== modified file 'database/schema/dbcontroller.py'
--- database/schema/dbcontroller.py	2012-09-28 06:15:58 +0000
+++ database/schema/dbcontroller.py	2019-03-05 13:35:13 +0000
@@ -39,7 +39,10 @@
     cur = con.cursor()
 
     # Force a WAL switch, returning the current position.
-    cur.execute('SELECT pg_switch_xlog()')
+    if con.server_version >= 100000:
+        cur.execute('SELECT pg_switch_wal()')
+    else:
+        cur.execute('SELECT pg_switch_xlog()')
     wal_point = cur.fetchone()[0]
     start_time = time.time()
     while timeout is None or time.time() < start_time + timeout:
@@ -103,7 +106,10 @@
             try:
                 con = pg_connect(conn_str)
                 cur = con.cursor()
-                cur.execute('select pg_xlog_replay_pause()')
+                if con.server_version >= 100000:
+                    cur.execute('select pg_wal_replay_pause()')
+                else:
+                    cur.execute('select pg_xlog_replay_pause()')
             except psycopg2.Error, x:
                 self.log.error(
                     'Unable to pause replication to %s (%s).'
@@ -119,7 +125,10 @@
             try:
                 con = pg_connect(conn_str)
                 cur = con.cursor()
-                cur.execute('select pg_xlog_replay_resume()')
+                if con.server_version >= 100000:
+                    cur.execute('select pg_wal_replay_resume()')
+                else:
+                    cur.execute('select pg_xlog_replay_resume()')
             except psycopg2.Error, x:
                 success = False
                 self.log.error(
@@ -140,11 +149,17 @@
             try:
                 con = pg_connect(conn_str)
                 cur = con.cursor()
-                cur.execute("SELECT pg_is_xlog_replay_paused()")
+                if con.server_version >= 100000:
+                    cur.execute("SELECT pg_is_wal_replay_paused()")
+                else:
+                    cur.execute("SELECT pg_is_xlog_replay_paused()")
                 replication_paused = cur.fetchone()[0]
                 if replication_paused:
                     self.log.warn("Replication paused on %s. Resuming.", name)
-                    cur.execute("SELECT pg_xlog_replay_resume()")
+                    if con.server_version >= 100000:
+                        cur.execute("SELECT pg_wal_replay_resume()")
+                    else:
+                        cur.execute("SELECT pg_xlog_replay_resume()")
                     wait_for_sync = True
             except psycopg2.Error, x:
                 success = False

=== modified file 'database/schema/full-update.py'
--- database/schema/full-update.py	2012-10-12 11:49:37 +0000
+++ database/schema/full-update.py	2019-03-05 13:35:13 +0000
@@ -175,9 +175,14 @@
         # Resume replication.
         replication_paused = not controller.resume_replication()
         if replication_paused:
-            log.error(
-                "Failed to resume replication. Run pg_xlog_replay_pause() "
-                "on all slaves to manually resume.")
+            if master_con.server_version >= 100000:
+                log.error(
+                    "Failed to resume replication. Run pg_wal_replay_pause() "
+                    "on all slaves to manually resume.")
+            else:
+                log.error(
+                    "Failed to resume replication. Run pg_xlog_replay_pause() "
+                    "on all slaves to manually resume.")
         else:
             if controller.sync():
                 log.info('Slaves in sync. Updates replicated.')