Add versioning to perf SQL database

perf/go/migratedb/main.go

Index: perf/go/migratedb/main.go
diff --git a/perf/go/migratedb/main.go b/perf/go/migratedb/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..67c94aa109a248b32adabe302770c37db6413940
--- /dev/null
+++ b/perf/go/migratedb/main.go
@@ -0,0 +1,64 @@
+package main
+
+// Executes database migrations to the latest target version. In production this
+// requires the root password for MySQL. The user will be prompted for that so
+// it is not entered via the command line.
+
+import (
+	"bufio"
+	"flag"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/golang/glog"
+	"skia.googlesource.com/buildbot.git/perf/go/db"
+)
+
+// flags
+var (
+	dbConnString = flag.String("db_conn_string", "root:%s@tcp(173.194.104.24:3306)/skia?parseTime=true", "\n\tDatabase string to open connect to the MySQL database. "+
+		"\n\tNeeds to follow the format of the golang-mysql driver (https://github.com/go-sql-driver/mysql."+
+		"\n\tIf the string contains %s the user will be prompted to enter a password which will then be used for subtitution.")
+)
+
+func main() {
+	flag.Parse()
+
+	var connectionStr = *dbConnString
+
+	// if it contains formatting information read the password from stdin.
+	if strings.Contains(connectionStr, "%s") {
+		glog.Infof("Using connection string: %s", connectionStr)
+		reader := bufio.NewReader(os.Stdin)
+		fmt.Print("Enter password for MySQL: ")
+		password, err := reader.ReadString('\n')
+		if err != nil {
+			glog.Fatalf("Unable to read password. Error: %s", err.Error())
+		}
+		connectionStr = fmt.Sprintf(connectionStr, strings.TrimRight(password, "\n"))
+	}
+
+	// Initialize the database.
+	db.Init(connectionStr)
+
+	// Get the current database version
+	maxDBVersion := db.MaxDBVersion()
+	glog.Infof("Latest database version: %d", maxDBVersion)
+
+	dbVersion, err := db.DBVersion()
+	if err != nil {
+		glog.Fatalf("Unable to retrieve database version. Error: %s", err.Error())
+	}
+	glog.Infof("Current database version: %d", dbVersion)
+
+	if dbVersion < maxDBVersion {
+		glog.Infof("Migrating to version: %d", maxDBVersion)
+		err = db.Migrate(maxDBVersion)
+		if err != nil {
+			glog.Fatalf("Unable to retrieve database version. Error: %s", err.Error())
+		}
+	}
+
+	glog.Infoln("Database migration finished.")
+}