Create new databases and change owners of existing ones during sync. (#153)

* Create new databases and change owners of existing ones during sync.

pkg/cluster/cluster.go

@@ -255,12 +255,12 @@ func (c *Cluster) Create() error {
 		if err = c.createRoles(); err != nil {
 			return fmt.Errorf("could not create users: %v", err)
 		}
+		c.logger.Infof("users have been successfully created")
 
 		if err = c.createDatabases(); err != nil {
 			return fmt.Errorf("could not create databases: %v", err)
 		}
-
-		c.logger.Infof("users have been successfully created")
+		c.logger.Infof("databases have been successfully created")
 	} else {
 		if c.masterLess {
 			c.logger.Warnln("cluster is masterless")

pkg/cluster/pg.go

@@ -25,8 +25,9 @@ const (
 	 WHERE a.rolname = ANY($1)
 	 ORDER BY 1;`
 
-	getDatabasesSQL   = `SELECT datname, a.rolname AS owner FROM pg_database d INNER JOIN pg_authid a ON a.oid = d.datdba;`
+	getDatabasesSQL       = `SELECT datname, pg_get_userbyid(datdba) AS owner FROM pg_database;`
 	createDatabaseSQL     = `CREATE DATABASE "%s" OWNER "%s";`
+	alterDatabaseOwnerSQL = `ALTER DATABASE "%s" OWNER TO "%s";`
 )
 
 func (c *Cluster) pgConnectionString() string {
@@ -137,6 +138,8 @@ func (c *Cluster) readPgUsersFromDatabase(userNames []string) (users spec.PgUser
 	return users, nil
 }
 
+// getDatabases returns the map of current databases with owners
+// The caller is responsible for opening and closing the database connection
 func (c *Cluster) getDatabases() (map[string]string, error) {
 	var (
 		rows *sql.Rows
@@ -144,15 +147,6 @@ func (c *Cluster) getDatabases() (map[string]string, error) {
 	)
 	dbs := make(map[string]string)
 
-	if err = c.initDbConn(); err != nil {
-		return nil, fmt.Errorf("could not init db connection")
-	}
-	defer func() {
-		if err = c.closeDbConn(); err != nil {
-			c.logger.Errorf("could not close db connection: %v", err)
-		}
-	}()
-
 	if rows, err = c.pgDb.Query(getDatabasesSQL); err != nil {
 		return nil, fmt.Errorf("could not query database: %v", err)
 	}
@@ -176,49 +170,44 @@ func (c *Cluster) getDatabases() (map[string]string, error) {
 	return dbs, nil
 }
 
-func (c *Cluster) createDatabases() error {
-	c.setProcessName("creating databases")
-
-	newDbs := c.Spec.Databases
-	curDbs, err := c.getDatabases()
-	if err != nil {
-		return fmt.Errorf("could not get current databases: %v", err)
-	}
-	for datname := range curDbs {
-		delete(newDbs, datname)
-	}
-
-	if len(newDbs) == 0 {
+// executeCreateDatabase creates new database with the given owner.
+// The caller is responsible for openinging and closing the database connection.
+func (c *Cluster) executeCreateDatabase(datname, owner string) error {
+	if !c.databaseNameOwnerValid(datname, owner) {
 		return nil
 	}
+	c.logger.Infof("creating database %q with owner %q", datname, owner)
 
-	if err = c.initDbConn(); err != nil {
-		return fmt.Errorf("could not init database connection")
+	if _, err := c.pgDb.Query(fmt.Sprintf(createDatabaseSQL, datname, owner)); err != nil {
+		return fmt.Errorf("could not execute create database: %v", err)
 	}
-	defer func() {
-		if err = c.closeDbConn(); err != nil {
-			c.logger.Errorf("could not close database connection: %v", err)
-		}
-	}()
+	return nil
+}
 
-	for datname, owner := range newDbs {
+// executeCreateDatabase changes the owner of the given database.
+// The caller is responsible for openinging and closing the database connection.
+func (c *Cluster) executeAlterDatabaseOwner(datname string, owner string) error {
+	if !c.databaseNameOwnerValid(datname, owner) {
+		return nil
+	}
+	c.logger.Infof("changing database %q owner to %q", datname, owner)
+	if _, err := c.pgDb.Query(fmt.Sprintf(alterDatabaseOwnerSQL, datname, owner)); err != nil {
+		return fmt.Errorf("could not execute alter database owner: %v", err)
+	}
+	return nil
+}
+
+func (c *Cluster) databaseNameOwnerValid(datname, owner string) bool {
 	if _, ok := c.pgUsers[owner]; !ok {
 		c.logger.Infof("skipping creation of the %q database, user %q does not exist", datname, owner)
-			continue
+		return false
 	}
 
 	if !databaseNameRegexp.MatchString(datname) {
 		c.logger.Infof("database %q has invalid name", datname)
-			continue
+		return false
 	}
-		c.logger.Infof("creating database %q with owner %q", datname, owner)
-
-		if _, err = c.pgDb.Query(fmt.Sprintf(createDatabaseSQL, datname, owner)); err != nil {
-			return fmt.Errorf("could not query database: %v", err)
-		}
-	}
-
-	return nil
+	return true
 }
 
 func makeUserFlags(rolsuper, rolinherit, rolcreaterole, rolcreatedb, rolcanlogin bool) (result []string) {

pkg/cluster/resources.go

@@ -557,3 +557,27 @@ func (c *Cluster) GetStatefulSet() *v1beta1.StatefulSet {
 func (c *Cluster) GetPodDisruptionBudget() *policybeta1.PodDisruptionBudget {
 	return c.PodDisruptionBudget
 }
+
+func (c *Cluster) createDatabases() error {
+	c.setProcessName("creating databases")
+
+	if len(c.Spec.Databases) == 0 {
+		return nil
+	}
+
+	if err := c.initDbConn(); err != nil {
+		return fmt.Errorf("could not init database connection")
+	}
+	defer func() {
+		if err := c.closeDbConn(); err != nil {
+			c.logger.Errorf("could not close database connection: %v", err)
+		}
+	}()
+
+	for datname, owner := range c.Spec.Databases {
+		if err := c.executeCreateDatabase(datname, owner); err != nil {
+			return err
+		}
+	}
+	return nil
+}

pkg/cluster/sync.go

@@ -90,6 +90,11 @@ func (c *Cluster) Sync(newSpec *spec.Postgresql) (err error) {
 			err = fmt.Errorf("could not sync roles: %v", err)
 			return
 		}
+		c.logger.Debugf("syncing databases")
+		if err = c.syncDatabases(); err != nil {
+			err = fmt.Errorf("could not sync databases: %v", err)
+			return
+		}
 	}
 
 	c.logger.Debugf("syncing persistent volumes")
@@ -292,3 +297,50 @@ func (c *Cluster) samePDBWith(pdb *policybeta1.PodDisruptionBudget) (match bool,
 
 	return
 }
+
+func (c *Cluster) syncDatabases() error {
+	c.setProcessName("syncing databases")
+
+	createDatabases := make(map[string]string)
+	alterOwnerDatabases := make(map[string]string)
+
+	if err := c.initDbConn(); err != nil {
+		return fmt.Errorf("could not init database connection")
+	}
+	defer func() {
+		if err := c.closeDbConn(); err != nil {
+			c.logger.Errorf("could not close database connection: %v", err)
+		}
+	}()
+
+	currentDatabases, err := c.getDatabases()
+	if err != nil {
+		return fmt.Errorf("could not get current databases: %v", err)
+	}
+
+	for datname, newOwner := range c.Spec.Databases {
+		currentOwner, exists := currentDatabases[datname]
+		if !exists {
+			createDatabases[datname] = newOwner
+		} else if currentOwner != newOwner {
+			alterOwnerDatabases[datname] = newOwner
+		}
+	}
+
+	if len(createDatabases)+len(alterOwnerDatabases) == 0 {
+		return nil
+	}
+
+	for datname, owner := range createDatabases {
+		if err = c.executeCreateDatabase(datname, owner); err != nil {
+			return err
+		}
+	}
+	for datname, owner := range alterOwnerDatabases {
+		if err = c.executeAlterDatabaseOwner(datname, owner); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}