Improve GUC handling

This PR improves GUC handling to be more inline with the Postgres GUC
system.

Makefile

@@ -37,7 +37,8 @@ SRCS = \
 	src/insert_chunk_state.c \
 	src/insert_statement_state.c \
 	src/ddl_utils.c \
-	src/agg_bookend.c
+	src/agg_bookend.c \
+	src/guc.c
 
 OBJS = $(SRCS:.c=.o)
 DEPS = $(SRCS:.c=.d)

src/guc.c

@@ -0,0 +1,60 @@
+#include <postgres.h>
+#include <utils/guc.h>
+
+#include "guc.h"
+
+bool		guc_disable_optimizations = false;
+bool		guc_optimize_non_hypertables = false;
+bool		guc_allow_install_without_preload = false;
+bool		guc_restoring = false;
+
+
+void
+_guc_init(void)
+{
+	/* Main database to connect to. */
+	DefineCustomBoolVariable("timescaledb.disable_optimizations", "Disable all timescale query optimizations",
+							 NULL,
+							 &guc_disable_optimizations,
+							 false,
+							 PGC_USERSET,
+							 0,
+							 NULL,
+							 NULL,
+							 NULL);
+	DefineCustomBoolVariable("timescaledb.optimize_non_hypertables", "Apply timescale query optimization to plain tables",
+							 "Apply timescale query optimization to plain tables in addition to hypertables",
+							 &guc_optimize_non_hypertables,
+							 false,
+							 PGC_USERSET,
+							 0,
+							 NULL,
+							 NULL,
+							 NULL);
+
+	DefineCustomBoolVariable("timescaledb.allow_install_without_preload", "Allow installing timescaledb without preloading the library (DANGEROUS)",
+							 NULL,
+							 &guc_allow_install_without_preload,
+							 false,
+							 PGC_USERSET,
+							 0,
+							 NULL,
+							 NULL,
+							 NULL);
+
+	DefineCustomBoolVariable("timescaledb.restoring", "Install timescale in restoring mode",
+							 "Used for running pg_restore",
+							 &guc_restoring,
+							 false,
+							 PGC_SUSET,
+							 0,
+							 NULL,
+							 NULL,
+							 NULL);
+
+}
+
+void
+_guc_fini(void)
+{
+}

src/guc.h

@@ -0,0 +1,12 @@
+#ifndef TIMESCALEDB_GUC_H
+#define TIMESCALEDB_GUC_H
+#include <postgres.h>
+
+extern bool guc_disable_optimizations;
+extern bool guc_optimize_non_hypertables;
+extern bool guc_allow_install_without_preload;
+
+void		_guc_init(void);
+void		_guc_fini(void);
+
+#endif   /* TIMESCALEDB_GUC_H */

src/init.c

@@ -6,6 +6,7 @@
 #include <utils/guc.h>
 
 #include "executor.h"
+#include "guc.h"
 
 #define MIN_SUPPORTED_VERSION_STR "9.6"
 #define MIN_SUPPORTED_VERSION_NUM 90600
@@ -41,22 +42,22 @@ _PG_init(void)
 {
 	if (!process_shared_preload_libraries_in_progress)
 	{
-	
-		char	   *force_load = GetConfigOptionByName("timescaledb.allow_install_without_preload", NULL, true);
-		if (force_load == NULL || strlen(force_load) != 2 || strncmp(force_load, "on", 2) != 0) {
+
+		if (!guc_allow_install_without_preload)
+		{
 			char	   *config_file = GetConfigOptionByName("config_file", NULL, false);
-			
-			ereport(ERROR, (errmsg("The timescaledb library is not preloaded"),
-                        errhint(
-"Please preload the timescaledb library via shared_preload_libraries.\n\n"
-"This can be done by editing the config file at: %1$s\n"
-"and adding 'timescaledb' to the list in the shared_preload_libraries config.\n"
-"	# Modify postgresql.conf:\n"
-"	shared_preload_libraries = 'timescaledb'\n\n"
-"Another way to do this, if not preloading other libraries, is with the command:\n"
-"	echo \"shared_preload_libraries = 'timescaledb'\" >> %1$s \n\n"
-"If you REALLY know what you are doing and would like to load the library without preloading, you can disable this check with: \n"
-"	SET timescaledb.allow_install_without_preload = 'on';", config_file)));
+
+			ereport(ERROR,
+					(errmsg("The timescaledb library is not preloaded"),
+					 errhint("Please preload the timescaledb library via shared_preload_libraries.\n\n"
+					 "This can be done by editing the config file at: %1$s\n"
+							 "and adding 'timescaledb' to the list in the shared_preload_libraries config.\n"
+							 "	# Modify postgresql.conf:\n	shared_preload_libraries = 'timescaledb'\n\n"
+							 "Another way to do this, if not preloading other libraries, is with the command:\n"
+							 "	echo \"shared_preload_libraries = 'timescaledb'\" >> %1$s \n\n"
+							 "(Will require a database restart.)\n\n"
+							 "If you REALLY know what you are doing and would like to load the library without preloading, you can disable this check with: \n"
+							 "	SET timescaledb.allow_install_without_preload = 'on';", config_file)));
 			return;
 		}
 	}
@@ -67,6 +68,7 @@ _PG_init(void)
 	_planner_init();
 	_executor_init();
 	_process_utility_init();
+	_guc_init();
 }
 
 void
@@ -76,6 +78,7 @@ _PG_fini(void)
 	 * Order of items should be strict reverse order of _PG_init. Please
 	 * document any exceptions.
 	 */
+	_guc_fini();
 	_process_utility_fini();
 	_executor_fini();
 	_planner_fini();

src/planner.c

@@ -20,6 +20,7 @@
 #include "partitioning.h"
 #include "extension.h"
 #include "utils.h"
+#include "guc.h"
 
 void		_planner_init(void);
 void		_planner_fini(void);
@@ -347,10 +348,6 @@ timescaledb_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
 	if (extension_is_loaded())
 	{
 		ChangeTableNameCtx context;
-		char	   *printParse = GetConfigOptionByName("io.print_parse", NULL, true);
-
-		/* set to false to not print all internal actions */
-		SetConfigOption("io.print_parse", "false", PGC_USERSET, PGC_S_SESSION);
 
 		/* replace call to main table with call to the replica table */
 		context.hcache = hypertable_cache_pin();
@@ -369,11 +366,6 @@ timescaledb_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
 
 		cache_release(context.hcache);
 
-		if (printParse != NULL && strcmp(printParse, "true") == 0)
-		{
-			pprint(parse);
-		}
-
 	}
 	if (prev_planner_hook != NULL)
 	{
@@ -394,8 +386,8 @@ timescaledb_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
 static inline bool
 should_optimize_query()
 {
-	return !util_config_default_off("timescaledb.disable_optimizations") &&
-		(util_config_default_off("timescaledb.optimize_plain_tables") || (global_planner_ctx != NULL && global_planner_ctx->has_hypertables));
+	return !guc_disable_optimizations &&
+		(guc_optimize_non_hypertables || (global_planner_ctx != NULL && global_planner_ctx->has_hypertables));
 }
 
 extern void sort_transform_optimization(PlannerInfo *root, RelOptInfo *rel);

src/utils.c

@@ -353,13 +353,3 @@ timestamptz_bucket(PG_FUNCTION_ARGS)
 	}
 	PG_RETURN_TIMESTAMPTZ(result);
 }
-
-inline bool
-util_config_default_off(const char *name)
-{
-	const char *result = GetConfigOption(name, true, true);
-
-	if (result != NULL && strlen(result) == 2 && strncmp(result, "on", 2) == 0)
-		return true;
-	return false;
-}

src/utils.h

@@ -36,7 +36,6 @@ extern char *internal_time_to_column_literal_sql(int64 internal_time, Oid type);
 extern FmgrInfo *create_fmgr(char *schema, char *function_name, int num_args);
 extern RangeVar *makeRangeVarFromRelid(Oid relid);
 extern int	int_cmp(const void *a, const void *b);
-extern bool util_config_default_off(const char *name);
 
 #define DATUM_GET(values, attno) \
 	values[attno-1]

test/expected/sql_query_results_optimized.out

@@ -468,7 +468,7 @@ LIMIT 2;
 
 --can turn on plain table optimizations
 BEGIN;
-    SET LOCAL timescaledb.optimize_plain_tables= 'on';
+    SET LOCAL timescaledb.optimize_non_hypertables = 'on';
     EXPLAIN (costs off)
     SELECT date_trunc('minute', time) t, avg(series_0), min(series_1), avg(series_2) 
     FROM plain_table 

test/expected/sql_query_results_unoptimized.out

@@ -439,7 +439,7 @@ LIMIT 2;
 
 --can turn on plain table optimizations
 BEGIN;
-    SET LOCAL timescaledb.optimize_plain_tables= 'on';
+    SET LOCAL timescaledb.optimize_non_hypertables = 'on';
     EXPLAIN (costs off)
     SELECT date_trunc('minute', time) t, avg(series_0), min(series_1), avg(series_2) 
     FROM plain_table 

test/sql/include/sql_query_results.sql

@@ -148,7 +148,7 @@ LIMIT 2;
 
 --can turn on plain table optimizations
 BEGIN;
-    SET LOCAL timescaledb.optimize_plain_tables= 'on';
+    SET LOCAL timescaledb.optimize_non_hypertables = 'on';
     EXPLAIN (costs off)
     SELECT date_trunc('minute', time) t, avg(series_0), min(series_1), avg(series_2) 
     FROM plain_table