pg_dump: Dump subscriptions by default

Dump subscriptions if the current user is a superuser, otherwise write a
warning and skip them.  Remove the pg_dump option
--include-subscriptions.

Discussion: https://www.postgresql.org/message-id/e4fbfad5-c6ac-fd50-6777-18c84b34eb2f@2ndquadrant.com

doc/src/sgml/logical-replication.sgml

@@ -167,9 +167,10 @@
   </para>
 
   <para>
-   Subscriptions are not dumped by <command>pg_dump</command> by default, but
-   this can be requested using the command-line
-   option <option>--include-subscriptions</option>.
+   Subscriptions are dumped by <command>pg_dump</command> if the current user
+   is a superuser.  Otherwise a warning is written and subscriptions are
+   skipped, because non-superusers cannot read all subscription information
+   from the <structname>pg_subscription</structname> catalog.
   </para>
 
   <para>

doc/src/sgml/ref/pg_dump.sgml

@@ -755,15 +755,6 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term><option>--include-subscriptions</option></term>
-      <listitem>
-       <para>
-        Include logical replication subscriptions in the dump.
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
       <term><option>--inserts</option></term>
       <listitem>

src/bin/pg_dump/pg_backup.h

@@ -119,7 +119,6 @@ typedef struct _restoreOptions
 	bool	   *idWanted;		/* array showing which dump IDs to emit */
 	int			enable_row_security;
 	int			sequence_data;	/* dump sequence data even in schema-only mode */
-	int			include_subscriptions;
 	int			binary_upgrade;
 } RestoreOptions;
 
@@ -154,7 +153,6 @@ typedef struct _dumpOptions
 	int			outputNoTablespaces;
 	int			use_setsessauth;
 	int			enable_row_security;
-	int			include_subscriptions;
 	int			no_subscription_connect;
 
 	/* default, if no "inclusion" switches appear, is to dump everything */

src/bin/pg_dump/pg_backup_archiver.c

@@ -171,7 +171,6 @@ dumpOptionsFromRestoreOptions(RestoreOptions *ropt)
 	dopt->include_everything = ropt->include_everything;
 	dopt->enable_row_security = ropt->enable_row_security;
 	dopt->sequence_data = ropt->sequence_data;
-	dopt->include_subscriptions = ropt->include_subscriptions;
 
 	return dopt;
 }

src/bin/pg_dump/pg_dump.c

@@ -342,7 +342,6 @@ main(int argc, char **argv)
 		{"enable-row-security", no_argument, &dopt.enable_row_security, 1},
 		{"exclude-table-data", required_argument, NULL, 4},
 		{"if-exists", no_argument, &dopt.if_exists, 1},
-		{"include-subscriptions", no_argument, &dopt.include_subscriptions, 1},
 		{"inserts", no_argument, &dopt.dump_inserts, 1},
 		{"lock-wait-timeout", required_argument, NULL, 2},
 		{"no-tablespaces", no_argument, &dopt.outputNoTablespaces, 1},
@@ -868,7 +867,6 @@ main(int argc, char **argv)
 	ropt->include_everything = dopt.include_everything;
 	ropt->enable_row_security = dopt.enable_row_security;
 	ropt->sequence_data = dopt.sequence_data;
-	ropt->include_subscriptions = dopt.include_subscriptions;
 	ropt->binary_upgrade = dopt.binary_upgrade;
 
 	if (compressLevel == -1)
@@ -951,7 +949,6 @@ help(const char *progname)
 			 "                               access to)\n"));
 	printf(_("  --exclude-table-data=TABLE   do NOT dump data for the named table(s)\n"));
 	printf(_("  --if-exists                  use IF EXISTS when dropping objects\n"));
-	printf(_("  --include-subscriptions      dump logical replication subscriptions\n"));
 	printf(_("  --inserts                    dump data as INSERT commands, rather than COPY\n"));
 	printf(_("  --no-security-labels         do not dump security label assignments\n"));
 	printf(_("  --no-subscription-connect    dump subscriptions so they don't connect on restore\n"));
@@ -3641,6 +3638,22 @@ dumpPublicationTable(Archive *fout, PublicationRelInfo *pubrinfo)
 	destroyPQExpBuffer(query);
 }
 
+/*
+ * Is the currently connected user a superuser?
+ */
+static bool
+is_superuser(Archive *fout)
+{
+	ArchiveHandle *AH = (ArchiveHandle *) fout;
+	const char *val;
+
+	val = PQparameterStatus(AH->connection, "is_superuser");
+
+	if (val && strcmp(val, "on") == 0)
+		return true;
+
+	return false;
+}
 
 /*
  * getSubscriptions
@@ -3649,7 +3662,6 @@ dumpPublicationTable(Archive *fout, PublicationRelInfo *pubrinfo)
 void
 getSubscriptions(Archive *fout)
 {
-	DumpOptions *dopt = fout->dopt;
 	PQExpBuffer query;
 	PGresult   *res;
 	SubscriptionInfo *subinfo;
@@ -3664,9 +3676,25 @@ getSubscriptions(Archive *fout)
 	int			i,
 				ntups;
 
-	if (!dopt->include_subscriptions || fout->remoteVersion < 100000)
+	if (fout->remoteVersion < 100000)
 		return;
 
+	if (!is_superuser(fout))
+	{
+		int n;
+
+		res = ExecuteSqlQuery(fout,
+							  "SELECT count(*) FROM pg_subscription "
+							  "WHERE subdbid = (SELECT oid FROM pg_catalog.pg_database"
+							  "                 WHERE datname = current_database())",
+							  PGRES_TUPLES_OK);
+		n = atoi(PQgetvalue(res, 0, 0));
+		if (n > 0)
+			write_msg(NULL, "WARNING: subscriptions not dumped because current user is not a superuser\n");
+		PQclear(res);
+		return;
+	}
+
 	query = createPQExpBuffer();
 
 	resetPQExpBuffer(query);
@@ -3714,6 +3742,9 @@ getSubscriptions(Archive *fout)
 		if (strlen(subinfo[i].rolname) == 0)
 			write_msg(NULL, "WARNING: owner of subscription \"%s\" appears to be invalid\n",
 					  subinfo[i].dobj.name);
+
+		/* Decide whether we want to dump it */
+		selectDumpableObject(&(subinfo[i].dobj), fout);
 	}
 	PQclear(res);
 
@@ -3735,7 +3766,7 @@ dumpSubscription(Archive *fout, SubscriptionInfo *subinfo)
 	int			npubnames = 0;
 	int			i;
 
-	if (dopt->dataOnly)
+	if (!(subinfo->dobj.dump & DUMP_COMPONENT_DEFINITION))
 		return;
 
 	delq = createPQExpBuffer();

src/bin/pg_dump/pg_restore.c

@@ -67,7 +67,6 @@ main(int argc, char **argv)
 	char	   *inputFileSpec;
 	static int	disable_triggers = 0;
 	static int	enable_row_security = 0;
-	static int	include_subscriptions = 0;
 	static int	if_exists = 0;
 	static int	no_data_for_failed_tables = 0;
 	static int	outputNoTablespaces = 0;
@@ -112,7 +111,6 @@ main(int argc, char **argv)
 		{"disable-triggers", no_argument, &disable_triggers, 1},
 		{"enable-row-security", no_argument, &enable_row_security, 1},
 		{"if-exists", no_argument, &if_exists, 1},
-		{"include-subscriptions", no_argument, &include_subscriptions, 1},
 		{"no-data-for-failed-tables", no_argument, &no_data_for_failed_tables, 1},
 		{"no-tablespaces", no_argument, &outputNoTablespaces, 1},
 		{"role", required_argument, NULL, 2},
@@ -353,7 +351,6 @@ main(int argc, char **argv)
 
 	opts->disable_triggers = disable_triggers;
 	opts->enable_row_security = enable_row_security;
-	opts->include_subscriptions = include_subscriptions;
 	opts->noDataForFailedTables = no_data_for_failed_tables;
 	opts->noTablespace = outputNoTablespaces;
 	opts->use_setsessauth = use_setsessauth;

src/bin/pg_dump/t/002_pg_dump.pl

@@ -43,7 +43,6 @@ my %pgdump_runs = (
 			'--format=custom',
 			"--file=$tempdir/binary_upgrade.dump",
 			'-w',
-			'--include-subscriptions', # XXX Should not be necessary?
 			'--schema-only',
 			'--binary-upgrade',
 			'-d', 'postgres',    # alternative way to specify database
@@ -58,7 +57,6 @@ my %pgdump_runs = (
 			'pg_dump',
 			'--no-sync',
 			"--file=$tempdir/clean.sql",
-			'--include-subscriptions',
 			'-c',
 			'-d', 'postgres',    # alternative way to specify database
 		], },
@@ -67,7 +65,6 @@ my %pgdump_runs = (
 			'pg_dump',
 			'--no-sync',
 			"--file=$tempdir/clean_if_exists.sql",
-			'--include-subscriptions',
 			'-c',
 			'--if-exists',
 			'--encoding=UTF8',    # no-op, just tests that option is accepted
@@ -85,7 +82,6 @@ my %pgdump_runs = (
 			'pg_dump',
 			'--no-sync',
 			"--file=$tempdir/createdb.sql",
-			'--include-subscriptions',
 			'-C',
 			'-R',                 # no-op, just for testing
 			'-v',
@@ -95,7 +91,6 @@ my %pgdump_runs = (
 			'pg_dump',
 			'--no-sync',
 			"--file=$tempdir/data_only.sql",
-			'--include-subscriptions',
 			'-a',
 			'--superuser=test_superuser',
 			'--disable-triggers',
@@ -253,7 +248,6 @@ my %pgdump_runs = (
 	section_pre_data => {
 		dump_cmd => [
 			'pg_dump',            "--file=$tempdir/section_pre_data.sql",
-			'--include-subscriptions',
 			'--section=pre-data', '--no-sync', 'postgres', ], },
 	section_data => {
 		dump_cmd => [
@@ -271,7 +265,7 @@ my %pgdump_runs = (
 	with_oids => {
 		dump_cmd => [
 			'pg_dump',                       '--oids',
-			'--include-subscriptions',       '--no-sync',
+			'--no-sync',
 			"--file=$tempdir/with_oids.sql", 'postgres', ], },);
 
 ###############################################################
@@ -1405,7 +1399,7 @@ my %tests = (
 	# catch-all for ALTER ... OWNER (except LARGE OBJECTs and PUBLICATIONs)
 	'ALTER ... OWNER commands (except LARGE OBJECTs and PUBLICATIONs)' => {
 		all_runs => 0,    # catch-all
-		regexp => qr/^ALTER (?!LARGE OBJECT|PUBLICATION)(.*) OWNER TO .*;/m,
+		regexp => qr/^ALTER (?!LARGE OBJECT|PUBLICATION|SUBSCRIPTION)(.*) OWNER TO .*;/m,
 		like   => {},     # use more-specific options above
 		unlike => {
 			column_inserts           => 1,
@@ -4318,25 +4312,25 @@ qr/CREATE TRANSFORM FOR integer LANGUAGE sql \(FROM SQL WITH FUNCTION pg_catalog
 			clean                    => 1,
 			clean_if_exists          => 1,
 			createdb                 => 1,
-			with_oids                => 1, },
-		unlike => {
 			defaults                 => 1,
 			exclude_test_table_data  => 1,
 			exclude_dump_test_schema => 1,
 			exclude_test_table       => 1,
-			section_pre_data         => 1,
 			no_blobs                 => 1,
 			no_privs                 => 1,
 			no_owner                 => 1,
+			pg_dumpall_dbprivs       => 1,
+			schema_only              => 1,
+			section_post_data        => 1,
+			with_oids                => 1, },
+		unlike => {
+			section_pre_data         => 1,
 			only_dump_test_schema    => 1,
 			only_dump_test_table     => 1,
-			pg_dumpall_dbprivs       => 1,
 			pg_dumpall_globals       => 1,
 			pg_dumpall_globals_clean => 1,
-			schema_only              => 1, # XXX Should be like?
 			role                     => 1,
-			section_pre_data         => 1, # XXX Should be like?
-			section_post_data        => 1,
+			section_pre_data         => 1,
 			test_schema_plus_blobs   => 1, }, },
 
 	'ALTER PUBLICATION pub1 ADD TABLE test_table' => {