Merge pull request #699 from mattermost/PLT-92

PLT-92 Adding server side versioning to the binary

store/sql_store.go

@@ -39,6 +39,7 @@ type SqlStore struct {
 	audit    AuditStore
 	session  SessionStore
 	oauth    OAuthStore
+	system   SystemStore
 }
 
 func NewSqlStore() Store {
@@ -56,9 +57,30 @@ func NewSqlStore() Store {
 			utils.Cfg.SqlSettings.Trace)
 	}
 
+	schemaVersion := sqlStore.GetCurrentSchemaVersion()
+
+	// If the version is already set then we are potentially in an 'upgrade needed' state
+	if schemaVersion != "" {
+		// Check to see if it's the most current database schema version
+		if !model.IsCurrentVersion(schemaVersion) {
+			// If we are upgrading from the previous version then print a warning and continue
+			if model.IsPreviousVersion(schemaVersion) {
+				l4g.Warn("The database schema version of " + schemaVersion + " appears to be out of date")
+				l4g.Warn("Attempting to upgrade the database schema version to " + model.CurrentVersion)
+			} else {
+				// If this is an 'upgrade needed' state but the user is attempting to skip a version then halt the world
+				l4g.Critical("The database schema version of " + schemaVersion + " cannot be upgraded.  You must not skip a version.")
+				time.Sleep(time.Second)
+				panic("The database schema version of " + schemaVersion + " cannot be upgraded.  You must not skip a version.")
+			}
+		}
+	}
+
 	// Temporary upgrade code, remove after 0.8.0 release
-	if sqlStore.DoesColumnExist("Sessions", "AltId") {
-		sqlStore.GetMaster().Exec("DROP TABLE IF EXISTS Sessions")
+	if sqlStore.DoesTableExist("Sessions") {
+		if sqlStore.DoesColumnExist("Sessions", "AltId") {
+			sqlStore.GetMaster().Exec("DROP TABLE IF EXISTS Sessions")
+		}
 	}
 
 	sqlStore.team = NewSqlTeamStore(sqlStore)
@@ -68,6 +90,7 @@ func NewSqlStore() Store {
 	sqlStore.audit = NewSqlAuditStore(sqlStore)
 	sqlStore.session = NewSqlSessionStore(sqlStore)
 	sqlStore.oauth = NewSqlOAuthStore(sqlStore)
+	sqlStore.system = NewSqlSystemStore(sqlStore)
 
 	sqlStore.master.CreateTablesIfNotExists()
 
@@ -78,6 +101,7 @@ func NewSqlStore() Store {
 	sqlStore.audit.(*SqlAuditStore).UpgradeSchemaIfNeeded()
 	sqlStore.session.(*SqlSessionStore).UpgradeSchemaIfNeeded()
 	sqlStore.oauth.(*SqlOAuthStore).UpgradeSchemaIfNeeded()
+	sqlStore.system.(*SqlSystemStore).UpgradeSchemaIfNeeded()
 
 	sqlStore.team.(*SqlTeamStore).CreateIndexesIfNotExists()
 	sqlStore.channel.(*SqlChannelStore).CreateIndexesIfNotExists()
@@ -86,6 +110,17 @@ func NewSqlStore() Store {
 	sqlStore.audit.(*SqlAuditStore).CreateIndexesIfNotExists()
 	sqlStore.session.(*SqlSessionStore).CreateIndexesIfNotExists()
 	sqlStore.oauth.(*SqlOAuthStore).CreateIndexesIfNotExists()
+	sqlStore.system.(*SqlSystemStore).CreateIndexesIfNotExists()
+
+	if model.IsPreviousVersion(schemaVersion) {
+		sqlStore.system.Update(&model.System{Name: "Version", Value: model.CurrentVersion})
+		l4g.Warn("The database schema has been upgraded to version " + model.CurrentVersion)
+	}
+
+	if schemaVersion == "" {
+		sqlStore.system.Save(&model.System{Name: "Version", Value: model.CurrentVersion})
+		l4g.Info("The database schema has been set to version " + model.CurrentVersion)
+	}
 
 	return sqlStore
 }
@@ -131,6 +166,56 @@ func setupConnection(con_type string, driver string, dataSource string, maxIdle
 	return dbmap
 }
 
+func (ss SqlStore) GetCurrentSchemaVersion() string {
+	version, _ := ss.GetMaster().SelectStr("SELECT Value FROM Systems WHERE Name='Version'")
+	return version
+}
+
+func (ss SqlStore) DoesTableExist(tableName string) bool {
+	if utils.Cfg.SqlSettings.DriverName == "postgres" {
+		count, err := ss.GetMaster().SelectInt(
+			`SELECT count(relname) FROM pg_class WHERE relname=$1`,
+			strings.ToLower(tableName),
+		)
+
+		if err != nil {
+			l4g.Critical("Failed to check if table exists %v", err)
+			time.Sleep(time.Second)
+			panic("Failed to check if table exists " + err.Error())
+		}
+
+		return count > 0
+
+	} else if utils.Cfg.SqlSettings.DriverName == "mysql" {
+
+		count, err := ss.GetMaster().SelectInt(
+			`SELECT
+		    COUNT(0) AS table_exists
+			FROM
+			    information_schema.TABLES
+			WHERE
+			    TABLE_SCHEMA = DATABASE()
+			        AND TABLE_NAME = ?
+		    `,
+			tableName,
+		)
+
+		if err != nil {
+			l4g.Critical("Failed to check if table exists %v", err)
+			time.Sleep(time.Second)
+			panic("Failed to check if table exists " + err.Error())
+		}
+
+		return count > 0
+
+	} else {
+		l4g.Critical("Failed to check if column exists because of missing driver")
+		time.Sleep(time.Second)
+		panic("Failed to check if column exists because of missing driver")
+	}
+
+}
+
 func (ss SqlStore) DoesColumnExist(tableName string, columnName string) bool {
 	if utils.Cfg.SqlSettings.DriverName == "postgres" {
 		count, err := ss.GetMaster().SelectInt(
@@ -380,6 +465,10 @@ func (ss SqlStore) OAuth() OAuthStore {
 	return ss.oauth
 }
 
+func (ss SqlStore) System() SystemStore {
+	return ss.system
+}
+
 type mattermConverter struct{}
 
 func (me mattermConverter) ToDb(val interface{}) (interface{}, error) {