From 521a7de793bfa49362916a2a3d8f8d66b8215bce Mon Sep 17 00:00:00 2001
From: WhereAreBugs <2572414306@qq.com>
Date: Sat, 16 Dec 2023 11:12:43 +0800
Subject: [PATCH] Fix(storage): fix an sql error when degrade version

Signed-off-by: WhereAreBugs <2572414306@qq.com>
---
 internal/storage/sql.go     | 62 ++++++++++++++++++++++++++++++-------
 internal/storage/storage.go | 33 ++++++++++++--------
 2 files changed, 71 insertions(+), 24 deletions(-)

diff --git a/internal/storage/sql.go b/internal/storage/sql.go
index 22e994ee6..ef2990a61 100644
--- a/internal/storage/sql.go
+++ b/internal/storage/sql.go
@@ -109,7 +109,7 @@ type Cluster struct {
 var (
 	// table: clusters
 	CreateClustersTable = `
-		CREATE TABLE IF NOT EXISTS clusters (
+		CREATE TABLE IF NOT EXISTS clusters_new (
 			id INTEGER PRIMARY KEY AUTOINCREMENT,
 			uuid TEXT NOT NULL,
 			name TEXT NOT NULL UNIQUE,
@@ -124,27 +124,67 @@ var (
 
 	// insert cluster
 	InsertCluster = `
-		INSERT INTO clusters(uuid, name, description, topology, type, pool, create_time)
+		INSERT INTO clusters_new(uuid, name, description, topology, type, pool, create_time)
 		VALUES(?, ?, ?, ?, ?, "", datetime('now','localtime'))
 	`
-	// check new cluster column
-	GetTypeFiled = `SELECT COUNT(*) FROM pragma_table_info('clusters') WHERE name = 'type'`
+	// check if view exists
+	isViewExist = `SELECT COUNT(*) FROM sqlite_master WHERE type='view' AND name = 'clusters'`
 
 	// update new cluster column
-	UpdateCluster = `ALTER TABLE clusters ADD COLUMN type TEXT NOT NULL DEFAULT 'develop'`
+	AddTypeField = `ALTER TABLE clusters_new ADD COLUMN type TEXT NOT NULL DEFAULT 'develop'`
+
+	// rename clusters table
+	RenameClusters = `ALTER TABLE clusters RENAME TO clusters_new`
+
+	// create view for old table
+	CreateClustersView = `
+		CREATE VIEW IF NOT EXISTS clusters AS
+		SELECT id, uuid, name, description, topology, pool, create_time, current
+		FROM clusters_new
+	`
+
+	// insert tigger
+	InsertTrigger = `
+		CREATE TRIGGER IF NOT EXISTS cluster_insert_trigger
+		INSTEAD OF INSERT ON clusters
+		FOR EACH ROW 
+		BEGIN 
+			INSERT INTO clusters_new VALUES (new.id, new.uuid, new.name, new.description, new.topology, new.pool, new.create_time, new.current,'develop');
+		END
+	`
+
+	// update trigger
+	UpdateTrigger = `
+		CREATE TRIGGER IF NOT EXISTS cluster_update_trigger
+		INSTEAD OF UPDATE ON clusters
+		FOR EACH ROW
+		BEGIN
+			UPDATE clusters_new SET uuid = new.uuid, name = new.name, description = new.description, topology = new.topology, pool = new.pool, create_time = new.create_time, current = new.current WHERE id = new.id;
+		END
+	`
+
+	// delete trigger
+	DeleteTrigger = `
+		CREATE TRIGGER IF NOT EXISTS cluster_delete_trigger
+		INSTEAD OF DELETE ON clusters
+		FOR EACH ROW
+		BEGIN
+			DELETE FROM clusters_new WHERE id = old.id;
+		END ;
+	`
 
 	// delete cluster
-	DeleteCluster = `DELETE from clusters WHERE name = ?`
+	DeleteCluster = `DELETE from clusters_new WHERE name = ?`
 
 	// select cluster
-	SelectCluster = `SELECT * FROM clusters WHERE name LIKE ?`
+	SelectCluster = `SELECT * FROM clusters_new WHERE name LIKE ?`
 
 	// get current cluster
-	GetCurrentCluster = `SELECT * FROM clusters WHERE current = 1`
+	GetCurrentCluster = `SELECT * FROM clusters_new WHERE current = 1`
 
 	// checkout cluster
 	CheckoutCluster = `
-		UPDATE clusters
+		UPDATE clusters_new
 		SET current = CASE name
 			WHEN ? THEN 1
 			ELSE 0
@@ -152,10 +192,10 @@ var (
 	`
 
 	// set cluster topology
-	SetClusterTopology = `UPDATE clusters SET topology = ? WHERE id = ?`
+	SetClusterTopology = `UPDATE clusters_new SET topology = ? WHERE id = ?`
 
 	// set cluster pool
-	SetClusterPool = `UPDATE clusters SET topology = ?, pool = ? WHERE id = ?`
+	SetClusterPool = `UPDATE clusters_new SET topology = ?, pool = ? WHERE id = ?`
 )
 
 // service
diff --git a/internal/storage/storage.go b/internal/storage/storage.go
index 49e6834b4..8e0302de2 100644
--- a/internal/storage/storage.go
+++ b/internal/storage/storage.go
@@ -82,6 +82,20 @@ func (s *Storage) init() error {
 		CreateAuditTable,
 		CreateMonitorTable,
 		CreateAnyTable,
+		CreateClustersView,
+		InsertTrigger,
+		UpdateTrigger,
+		DeleteTrigger,
+	}
+
+	tablesOK, err := s.CheckViewExists()
+	if err != nil {
+		return err
+	}
+	if !tablesOK {
+		// allow failed to execute
+		_, err = s.db.Write(RenameClusters)
+		_, err = s.db.Write(AddTypeField)
 	}
 
 	for _, sql := range sqls {
@@ -91,14 +105,7 @@ func (s *Storage) init() error {
 		}
 	}
 
-	flag, err := s.CheckTypeFiledExist()
-	if err != nil {
-		return err
-	}
-	if !flag {
-		_, err = s.db.Write(UpdateCluster)
-	}
-	return err
+	return nil
 }
 
 func (s *Storage) write(query string, args ...any) error {
@@ -171,22 +178,22 @@ func (s *Storage) InsertCluster(name, uuid, description, topology, deployType st
 	return s.write(InsertCluster, uuid, name, description, topology, deployType)
 }
 
-func (s *Storage) CheckTypeFiledExist() (bool, error) {
-	result, err := s.db.Query(GetTypeFiled)
+func (s *Storage) CheckViewExists() (bool, error) {
+	result, err := s.db.Query(isViewExist)
 	if err != nil {
 		return false, err
 	}
 	defer result.Close()
 
-	var isFiledExist bool
+	var exists bool
 	for result.Next() {
-		err = result.Scan(&isFiledExist)
+		err = result.Scan(&exists)
 		if err != nil {
 			return false, err
 		}
 		break
 	}
-	return isFiledExist, nil
+	return exists, nil
 }
 
 func (s *Storage) DeleteCluster(name string) error {