sql: move Triggers to server

Introduced sql_triggers field in space structure.
Changed parser logic to do not insert built triggers, just only
to do parsing. All triggers insertions and deletions are operated
via on_replace_dd_trigger now.

Resolves #3273.

src/box/alter.cc

@@ -551,6 +551,9 @@ space_swap_triggers(struct space *new_space, struct space *old_space)
 	rlist_swap(&new_space->before_replace, &old_space->before_replace);
 	rlist_swap(&new_space->on_replace, &old_space->on_replace);
 	rlist_swap(&new_space->on_stmt_begin, &old_space->on_stmt_begin);
+	/** Copy SQL Triggers pointer. */
+	new_space->sql_triggers = old_space->sql_triggers;
+	old_space->sql_triggers = NULL;
 }
 
 /**
@@ -732,7 +735,6 @@ alter_space_commit(struct trigger *trigger, void *event)
 	}
 
 	trigger_run_xc(&on_alter_space, alter->new_space);
-
 	alter->new_space = NULL; /* for alter_space_delete(). */
 	/*
 	 * Delete the old version of the space, we are not
@@ -3100,6 +3102,39 @@ on_replace_dd_trigger(struct trigger * /* trigger */, void *event)
 {
 	struct txn *txn = (struct txn *) event;
 	txn_check_singlestatement_xc(txn, "Space _trigger");
+
+	struct txn_stmt *stmt = txn_current_stmt(txn);
+	if (stmt->old_tuple != NULL) {
+		uint32_t trigger_name_len;
+		const char *trigger_name_src =
+			tuple_field_str_xc(stmt->old_tuple, 0,
+					   &trigger_name_len);
+		if (sql_trigger_delete_by_name(sql_get(), trigger_name_src,
+					       trigger_name_len) != 0)
+			diag_raise();
+	}
+	if (stmt->new_tuple != NULL) {
+		uint32_t trigger_name_len;
+		const char *trigger_name_src =
+			tuple_field_str_xc(stmt->new_tuple, 0,
+					   &trigger_name_len);
+		const char *space_opts =
+			tuple_field_with_type_xc(stmt->new_tuple, 1, MP_MAP);
+		struct space_opts opts;
+		struct region *region = &fiber()->gc;
+		space_opts_decode(&opts, space_opts, region);
+		struct Trigger *trigger =
+			sql_trigger_compile(sql_get(), opts.sql);
+		if (trigger == NULL)
+			diag_raise();
+		auto trigger_guard = make_scoped_guard([=] {
+		    sql_trigger_delete(sql_get(), trigger);
+		});
+		if (sql_trigger_insert(trigger, trigger_name_src,
+				       trigger_name_len) != 0)
+			diag_raise();
+		trigger_guard.is_active = false;
+	}
 }
 
 struct trigger alter_space_on_replace_space = {

src/box/errcode.h

@@ -107,7 +107,7 @@ struct errcode_record {
 	/* 52 */_(ER_FUNCTION_EXISTS,		"Function '%s' already exists") \
 	/* 53 */_(ER_BEFORE_REPLACE_RET,	"Invalid return value of space:before_replace trigger: expected tuple or nil, got %s") \
 	/* 54 */_(ER_FUNCTION_MAX,		"A limit on the total number of functions has been reached: %u") \
-	/* 55 */_(ER_UNUSED4,			"") \
+	/* 55 */_(ER_TRIGGER_EXISTS,		"Trigger '%s' already exists") \
 	/* 56 */_(ER_USER_MAX,			"A limit on the total number of users has been reached: %u") \
 	/* 57 */_(ER_NO_SUCH_ENGINE,		"Space engine '%s' does not exist") \
 	/* 58 */_(ER_RELOAD_CFG,		"Can't set option '%s' dynamically") \

src/box/space.h

@@ -146,6 +146,8 @@ struct space {
 	struct rlist on_replace;
 	/** Triggers fired before space statement */
 	struct rlist on_stmt_begin;
+	/** SQL Trigger list. */
+	struct Trigger *sql_triggers;
 	/**
 	 * The number of *enabled* indexes in the space.
 	 *

src/box/sql.c

@@ -1223,9 +1223,6 @@ space_foreach_put_cb(struct space *space, void *udata)
 /* Load database schema from Tarantool. */
 void tarantoolSqlite3LoadSchema(InitData *init)
 {
-	box_iterator_t *it;
-	box_tuple_t *tuple;
-
 	sql_schema_put(
 		init, TARANTOOL_SYS_SCHEMA_NAME,
 		BOX_SCHEMA_ID, 0,
@@ -1294,42 +1291,6 @@ void tarantoolSqlite3LoadSchema(InitData *init)
 		init->rc = SQL_TARANTOOL_ERROR;
 		return;
 	}
-
-	/* Read _trigger */
-	it = box_index_iterator(BOX_TRIGGER_ID, 0, ITER_GE,
-				nil_key, nil_key + sizeof(nil_key));
-
-	if (it == NULL) {
-		init->rc = SQL_TARANTOOL_ITERATOR_FAIL;
-		return;
-	}
-
-	while (box_iterator_next(it, &tuple) == 0 && tuple != NULL) {
-		const char *field, *ptr;
-		char *name, *sql;
-		unsigned len;
-		assert(tuple_field_count(tuple) == 2);
-
-		field = tuple_field(tuple, 0);
-		assert (field != NULL);
-		ptr = mp_decode_str(&field, &len);
-		name = strndup(ptr, len);
-
-		field = tuple_field(tuple, 1);
-		assert (field != NULL);
-		mp_decode_array(&field);
-		ptr = mp_decode_str(&field, &len);
-		assert (strncmp(ptr, "sql", 3) == 0);
-
-		ptr = mp_decode_str(&field, &len);
-		sql = strndup(ptr, len);
-
-		sql_schema_put(init, name, 0, 0, sql);
-
-		free(name);
-		free(sql);
-	}
-	box_iterator_free(it);
 }
 
 /*********************************************************************
@@ -1737,6 +1698,15 @@ space_column_default_expr(uint32_t space_id, uint32_t fieldno)
 	return space->def->fields[fieldno].default_value_expr;
 }
 
+struct Trigger *
+space_trigger_list(uint32_t space_id)
+{
+	struct space *space = space_cache_find(space_id);
+	assert(space != NULL);
+	assert(space->def != NULL);
+	return space->sql_triggers;
+}
+
 struct space_def *
 sql_ephemeral_space_def_new(Parse *parser, const char *name)
 {

src/box/sql.h

@@ -83,6 +83,17 @@ struct Trigger;
 struct Expr *
 sql_expr_compile(struct sqlite3 *db, const char *expr, int expr_len);
 
+/**
+ * Perform parsing of provided SQL request and construct trigger AST.
+ * @param db SQL context handle.
+ * @param sql request to parse.
+ *
+ * @retval NULL on error
+ * @retval not NULL Trigger AST pointer on success.
+ */
+struct Trigger *
+sql_trigger_compile(struct sqlite3 *db, const char *sql);
+
 /**
  * Free AST pointed by trigger.
  * @param db SQL handle.
@@ -91,6 +102,39 @@ sql_expr_compile(struct sqlite3 *db, const char *expr, int expr_len);
 void
 sql_trigger_delete(struct sqlite3 *db, struct Trigger *trigger);
 
+/**
+ * Remove a trigger from the hash tables of the sqlite* pointer.
+ * @param db SQL handle.
+ * @param name a name of trigger object to delete.
+ * @param name_len length of the name.
+ *
+ * @retval 0 on success.
+ * @retval -1 on error.
+ */
+int
+sql_trigger_delete_by_name(struct sqlite3 *db, const char *name, int name_len);
+
+/**
+ * Get server triggers list by space_id.
+ * @param space_id Space ID.
+ *
+ * @retval trigger AST list.
+ */
+struct Trigger *
+space_trigger_list(uint32_t space_id);
+
+/**
+ * Perform insert trigger in appropriate space.
+ * @param trigger object to append.
+ * @param name  a name of trigger object to insert.
+ * @param name_len length of the name.
+ *
+ * @retval 0 on success.
+ * @retval -1 on error.
+ */
+int
+sql_trigger_insert(struct Trigger *trigger, const char *name, int name_len);
+
 /**
  * Store duplicate of a parsed expression into @a parser.
  * @param parser Parser context.

src/box/sql/build.c

@@ -2289,16 +2289,14 @@ sql_code_drop_table(struct Parse *parse_context, struct space *space,
 	/*
 	 * Drop all triggers associated with the table being
 	 * dropped. Code is generated to remove entries from
-	 * _trigger. OP_DropTrigger will remove it from internal
-	 * SQL structures.
+	 * _trigger. on_replace_dd_trigger will remove it from
+	 * internal SQL structures.
 	 *
 	 * Do not account triggers deletion - they will be
 	 * accounted in DELETE from _space below.
 	 */
 	parse_context->nested++;
-	Table *table = sqlite3HashFind(&parse_context->db->pSchema->tblHash,
-				       space->def->name);
-	struct Trigger *trigger = table->pTrigger;
+	struct Trigger *trigger = space->sql_triggers;
 	while (trigger != NULL) {
 		sqlite3DropTriggerPtr(parse_context, trigger);
 		trigger = trigger->pNext;

src/box/sql/fkey.c

@@ -1440,7 +1440,6 @@ fkActionTrigger(Parse * pParse,	/* Parse context */
 		}
 		pStep->pTrig = pTrigger;
 		pTrigger->pSchema = pTab->pSchema;
-		pTrigger->pTabSchema = pTab->pSchema;
 		pFKey->apTrigger[iAction] = pTrigger;
 		pTrigger->op = (pChanges ? TK_UPDATE : TK_DELETE);
 	}

src/box/sql/insert.c

@@ -1766,9 +1766,9 @@ xferOptimization(Parse * pParse,	/* Parser context */
 		 */
 		return 0;
 	}
-	if (pDest->pTrigger) {
-		return 0;	/* tab1 must not have triggers */
-	}
+	/* The pDest must not have triggers. */
+	if (space_trigger_list(pDest->def->id) != NULL)
+		return 0;
 	if (onError == ON_CONFLICT_ACTION_DEFAULT) {
 		if (pDest->iPKey >= 0)
 			onError = pDest->keyConf;

src/box/sql/sqliteInt.h

@@ -1935,7 +1935,6 @@ struct Table {
 #ifndef SQLITE_OMIT_ALTERTABLE
 	int addColOffset;	/* Offset in CREATE TABLE stmt to add a new column */
 #endif
-	Trigger *pTrigger;	/* List of triggers stored in pSchema */
 	Schema *pSchema;	/* Schema that contains this table */
 	Table *pNextZombie;	/* Next on the Parse.pZombieTab list */
 	/** Space definition with Tarantool metadata. */
@@ -3032,14 +3031,14 @@ struct Parse {
  */
 struct Trigger {
 	char *zName;		/* The name of the trigger                        */
-	char *table;		/* The table or view to which the trigger applies */
+	/** The ID of space the triggers is refer to. */
+	uint32_t space_id;
 	u8 op;			/* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
 	u8 tr_tm;		/* One of TRIGGER_BEFORE, TRIGGER_AFTER */
 	Expr *pWhen;		/* The WHEN clause of the expression (may be NULL) */
 	IdList *pColumns;	/* If this is an UPDATE OF <column-list> trigger,
 				   the <column-list> is stored here */
 	Schema *pSchema;	/* Schema containing the trigger */
-	Schema *pTabSchema;	/* Schema containing the table */
 	TriggerStep *step_list;	/* Link list of trigger program steps             */
 	Trigger *pNext;		/* Next trigger associated with the table */
 };
@@ -4027,7 +4026,6 @@ TriggerStep *sqlite3TriggerInsertStep(sqlite3 *, Token *, IdList *,
 TriggerStep *sqlite3TriggerUpdateStep(sqlite3 *, Token *, ExprList *, Expr *,
 				      u8);
 TriggerStep *sqlite3TriggerDeleteStep(sqlite3 *, Token *, Expr *);
-void sqlite3UnlinkAndDeleteTrigger(sqlite3 *, const char *);
 u32 sqlite3TriggerColmask(Parse *, Trigger *, ExprList *, int, int, Table *,
 			  int);
 #define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))

src/box/sql/tokenize.c

@@ -39,6 +39,7 @@
 #include <stdlib.h>
 #include <unicode/utf8.h>
 #include <unicode/uchar.h>
+#include "box/schema.h"
 
 #include "say.h"
 #include "sqliteInt.h"
@@ -122,6 +123,7 @@ static const char sql_ascii_class[] = {
  * the #include below.
  */
 #include "keywordhash.h"
+#include "tarantoolInt.h"
 
 #define maybe_utf8(c) ((sqlite3CtypeMap[c] & 0x40) != 0)
 
@@ -510,8 +512,13 @@ sqlite3RunParser(Parse * pParse, const char *zSql, char **pzErrMsg)
 	}
 	if (pParse->rc != SQLITE_OK && pParse->rc != SQLITE_DONE
 	    && pParse->zErrMsg == 0) {
-		pParse->zErrMsg =
-		    sqlite3MPrintf(db, "%s", sqlite3ErrStr(pParse->rc));
+		const char *error;
+		if (is_tarantool_error(pParse->rc) && tarantoolErrorMessage()) {
+			error = tarantoolErrorMessage();
+		} else {
+			error = sqlite3ErrStr(pParse->rc);
+		}
+		pParse->zErrMsg = sqlite3MPrintf(db, "%s", error);
 	}
 	assert(pzErrMsg != 0);
 	if (pParse->zErrMsg) {
@@ -528,7 +535,12 @@ sqlite3RunParser(Parse * pParse, const char *zSql, char **pzErrMsg)
 
 	if (pParse->pWithToFree)
 		sqlite3WithDelete(db, pParse->pWithToFree);
-	sql_trigger_delete(db, pParse->pNewTrigger);
+	/*
+	 * Trigger is exporting with pNewTrigger field when
+	 * parse_only flag is set.
+	 */
+	if (!pParse->parse_only)
+		sql_trigger_delete(db, pParse->pNewTrigger);
 	sqlite3DbFree(db, pParse->pVList);
 	while (pParse->pZombieTab) {
 		Table *p = pParse->pZombieTab;
@@ -569,3 +581,23 @@ sql_expr_compile(sqlite3 *db, const char *expr, int expr_len)
 	sql_parser_destroy(&parser);
 	return expression;
 }
+
+struct Trigger *
+sql_trigger_compile(struct sqlite3 *db, const char *sql)
+{
+	struct Parse parser;
+	sql_parser_create(&parser, db);
+	parser.parse_only = true;
+	char *sql_error;
+	struct Trigger *trigger = NULL;
+	if (sqlite3RunParser(&parser, sql, &sql_error) != SQLITE_OK) {
+		char *error = tt_static_buf();
+		snprintf(error, TT_STATIC_BUF_LEN, "%s", sql_error);
+		diag_set(ClientError, ER_SQL_EXECUTE, sql);
+		goto cleanup;
+	}
+	trigger = parser.pNewTrigger;
+cleanup:
+	sql_parser_destroy(&parser);
+	return trigger;
+}