Use change from outbrain/golib PR

go/logic/migrator.go

@@ -20,6 +20,7 @@ import (
 	"github.com/github/gh-ost/go/sql"
 
 	"github.com/outbrain/golib/log"
+	"github.com/outbrain/golib/sqlutils"
 )
 
 type ChangelogState string
@@ -1225,6 +1226,7 @@ func (this *Migrator) finalCleanup() error {
 	this.finishedMigrating = true
 	this.applier.FinalCleanup()
 	this.eventsStreamer.FinalCleanup()
+	sqlutils.ResetDBCache()
 
 	return nil
 }

vendor/github.com/outbrain/golib/sqlutils/sqlutils.go

@@ -144,6 +144,17 @@ func GetDB(mysql_uri string) (*sql.DB, bool, error) {
 	return knownDBs[mysql_uri], exists, nil
 }
 
+// Resets the knownDBs cache, used when the DB connections have been closed,
+//   and new connections are needed to access the DB
+func ResetDBCache() {
+	knownDBsMutex.Lock()
+	defer func() {
+		knownDBsMutex.Unlock()
+	}()
+
+	knownDBs = make(map[string]*sql.DB)
+}
+
 // RowToArray is a convenience function, typically not called directly, which maps a
 // single read database row into a NullString
 func RowToArray(rows *sql.Rows, columns []string) []CellData {