Add udf citus_get_active_worker_nodes

src/backend/distributed/operations/node_protocol.c

@@ -85,6 +85,7 @@ PG_FUNCTION_INFO_V1(master_get_table_ddl_events);
 PG_FUNCTION_INFO_V1(master_get_new_shardid);
 PG_FUNCTION_INFO_V1(master_get_new_placementid);
 PG_FUNCTION_INFO_V1(master_get_active_worker_nodes);
+PG_FUNCTION_INFO_V1(citus_get_active_worker_nodes);
 PG_FUNCTION_INFO_V1(master_get_round_robin_candidate_nodes);
 PG_FUNCTION_INFO_V1(master_stage_shard_row);
 PG_FUNCTION_INFO_V1(master_stage_shard_placement_row);
@@ -442,12 +443,12 @@ master_stage_shard_placement_row(PG_FUNCTION_ARGS)
 
 
 /*
- * master_get_active_worker_nodes returns a set of active worker host names and
+ * citus_get_active_worker_nodes returns a set of active worker host names and
  * port numbers in deterministic order. Currently we assume that all worker
  * nodes in pg_dist_node are active.
  */
 Datum
-master_get_active_worker_nodes(PG_FUNCTION_ARGS)
+citus_get_active_worker_nodes(PG_FUNCTION_ARGS)
 {
 	FuncCallContext *functionContext = NULL;
 	uint32 workerNodeIndex = 0;
@@ -512,6 +513,16 @@ master_get_active_worker_nodes(PG_FUNCTION_ARGS)
 }
 
 
+/*
+ * master_get_active_worker_nodes is a wrapper function for old UDF name.
+ */
+Datum
+master_get_active_worker_nodes(PG_FUNCTION_ARGS)
+{
+	return citus_get_active_worker_nodes(fcinfo);
+}
+
+
 /* Finds the relationId from a potentially qualified relation name. */
 Oid
 ResolveRelationId(text *relationName, bool missingOk)

src/backend/distributed/sql/citus--10.0-2--10.0-3.sql

@@ -8,3 +8,11 @@ RETURNS VOID
     AS 'MODULE_PATHNAME', $$citus_update_table_statistics$$;
 COMMENT ON FUNCTION pg_catalog.master_update_table_statistics(regclass)
 	IS 'updates shard statistics of the given table';
+
+CREATE OR REPLACE FUNCTION pg_catalog.citus_get_active_worker_nodes(OUT node_name text, OUT node_port bigint)
+    RETURNS SETOF record
+    LANGUAGE C STRICT ROWS 100
+    AS 'MODULE_PATHNAME', $$citus_get_active_worker_nodes$$;
+COMMENT ON FUNCTION pg_catalog.citus_get_active_worker_nodes()
+    IS 'fetch set of active worker nodes';
+

src/backend/distributed/sql/downgrades/citus--10.0-3--10.0-2.sql

@@ -22,3 +22,5 @@ END;
 $$ LANGUAGE 'plpgsql';
 COMMENT ON FUNCTION master_update_table_statistics(regclass)
 	IS 'updates shard statistics of the given table and its colocated tables';
+
+DROP FUNCTION pg_catalog.citus_get_active_worker_nodes(OUT text, OUT bigint);

src/test/regress/expected/multi_extension.out

@@ -531,8 +531,8 @@ SELECT * FROM print_extension_changes();
 ---------------------------------------------------------------------
 (0 rows)
 
--- Test downgrade to 10.0-2 from 10.1-1
-ALTER EXTENSION citus UPDATE TO '10.1-1';
+-- Test downgrade to 10.0-2 from 10.0-3
+ALTER EXTENSION citus UPDATE TO '10.0-3';
 ALTER EXTENSION citus UPDATE TO '10.0-2';
 -- Should be empty result since upgrade+downgrade should be a no-op
 SELECT * FROM print_extension_changes();
@@ -540,10 +540,27 @@ SELECT * FROM print_extension_changes();
 ---------------------------------------------------------------------
 (0 rows)
 
+-- Snapshot of state at 10.0-3
+ALTER EXTENSION citus UPDATE TO '10.0-3';
+SELECT * FROM print_extension_changes();
+ previous_object |              current_object
+---------------------------------------------------------------------
+                 | function citus_get_active_worker_nodes()
+(1 row)
+
+-- Test downgrade to 10.0-3 from 10.1-1
+ALTER EXTENSION citus UPDATE TO '10.1-1';
+ALTER EXTENSION citus UPDATE TO '10.0-3';
+-- Should be empty result since upgrade+downgrade should be a no-op
+SELECT * FROM print_extension_changes();
+ previous_object | current_object
+---------------------------------------------------------------------
+(0 rows)
+
 -- Snapshot of state at 10.1-1
 ALTER EXTENSION citus UPDATE TO '10.1-1';
 SELECT * FROM print_extension_changes();
- previous_object | current_object
+ previous_object |              current_object
 ---------------------------------------------------------------------
 (0 rows)
 

src/test/regress/expected/multi_extension_0.out

@@ -527,8 +527,8 @@ SELECT * FROM print_extension_changes();
 ---------------------------------------------------------------------
 (0 rows)
 
--- Test downgrade to 10.0-2 from 10.1-1
-ALTER EXTENSION citus UPDATE TO '10.1-1';
+-- Test downgrade to 10.0-2 from 10.0-3
+ALTER EXTENSION citus UPDATE TO '10.0-3';
 ALTER EXTENSION citus UPDATE TO '10.0-2';
 -- Should be empty result since upgrade+downgrade should be a no-op
 SELECT * FROM print_extension_changes();
@@ -536,10 +536,27 @@ SELECT * FROM print_extension_changes();
 ---------------------------------------------------------------------
 (0 rows)
 
+-- Snapshot of state at 10.0-3
+ALTER EXTENSION citus UPDATE TO '10.0-3';
+SELECT * FROM print_extension_changes();
+ previous_object |              current_object
+---------------------------------------------------------------------
+                 | function citus_get_active_worker_nodes()
+(1 row)
+
+-- Test downgrade to 10.0-3 from 10.1-1
+ALTER EXTENSION citus UPDATE TO '10.1-1';
+ALTER EXTENSION citus UPDATE TO '10.0-3';
+-- Should be empty result since upgrade+downgrade should be a no-op
+SELECT * FROM print_extension_changes();
+ previous_object | current_object
+---------------------------------------------------------------------
+(0 rows)
+
 -- Snapshot of state at 10.1-1
 ALTER EXTENSION citus UPDATE TO '10.1-1';
 SELECT * FROM print_extension_changes();
- previous_object | current_object
+ previous_object |              current_object
 ---------------------------------------------------------------------
 (0 rows)
 

src/test/regress/expected/upgrade_list_citus_objects.out

@@ -55,6 +55,7 @@ ORDER BY 1;
  function citus_executor_name(integer)
  function citus_extradata_container(internal)
  function citus_finish_pg_upgrade()
+ function citus_get_active_worker_nodes()
  function citus_internal.columnar_ensure_objects_exist()
  function citus_internal.find_groupid_for_node(text,integer)
  function citus_internal.pg_dist_node_trigger_func()
@@ -242,5 +243,5 @@ ORDER BY 1;
  view citus_worker_stat_activity
  view pg_dist_shard_placement
  view time_partitions
-(226 rows)
+(227 rows)
 

src/test/regress/expected/upgrade_list_citus_objects_0.out

@@ -52,6 +52,7 @@ ORDER BY 1;
  function citus_executor_name(integer)
  function citus_extradata_container(internal)
  function citus_finish_pg_upgrade()
+ function citus_get_active_worker_nodes()
  function citus_internal.columnar_ensure_objects_exist()
  function citus_internal.find_groupid_for_node(text,integer)
  function citus_internal.pg_dist_node_trigger_func()
@@ -238,5 +239,5 @@ ORDER BY 1;
  view citus_worker_stat_activity
  view pg_dist_shard_placement
  view time_partitions
-(222 rows)
+(223 rows)
 

src/test/regress/sql/multi_extension.sql

@@ -208,12 +208,22 @@ SELECT * FROM print_extension_changes();
 ALTER EXTENSION citus UPDATE TO '10.0-2';
 SELECT * FROM print_extension_changes();
 
--- Test downgrade to 10.0-2 from 10.1-1
-ALTER EXTENSION citus UPDATE TO '10.1-1';
+-- Test downgrade to 10.0-2 from 10.0-3
+ALTER EXTENSION citus UPDATE TO '10.0-3';
 ALTER EXTENSION citus UPDATE TO '10.0-2';
 -- Should be empty result since upgrade+downgrade should be a no-op
 SELECT * FROM print_extension_changes();
 
+-- Snapshot of state at 10.0-3
+ALTER EXTENSION citus UPDATE TO '10.0-3';
+SELECT * FROM print_extension_changes();
+
+-- Test downgrade to 10.0-3 from 10.1-1
+ALTER EXTENSION citus UPDATE TO '10.1-1';
+ALTER EXTENSION citus UPDATE TO '10.0-3';
+-- Should be empty result since upgrade+downgrade should be a no-op
+SELECT * FROM print_extension_changes();
+
 -- Snapshot of state at 10.1-1
 ALTER EXTENSION citus UPDATE TO '10.1-1';
 SELECT * FROM print_extension_changes();