Overhaul database package

datahopper/go/buildbot_migratedb/main.go

+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 (
+        "flag"
+
+        "github.com/golang/glog"
+        "skia.googlesource.com/buildbot.git/go/buildbot"
+        "skia.googlesource.com/buildbot.git/go/common"
+        "skia.googlesource.com/buildbot.git/go/database"
+)
+
+var (
+        local = flag.Bool("local", false, "Running locally if true. As opposed to in production.")
+)
+
+func main() {
+        // Set up flags.
+        database.SetupFlags(buildbot.PROD_DB_HOST, buildbot.PROD_DB_PORT, database.USER_ROOT, buildbot.PROD_DB_NAME)
+
+        // Global init to initialize glog and parse arguments.
+        common.Init()
+
+        conf, err := database.ConfigFromFlagsAndMetadata(*local, buildbot.MigrationSteps())
+        if err != nil {
+                glog.Fatal(err)
+        }
+        vdb := database.NewVersionedDB(conf)
+
+        // Get the current database version
+        maxDBVersion := vdb.MaxDBVersion()
+        glog.Infof("Latest database version: %d", maxDBVersion)
+
+        dbVersion, err := vdb.DBVersion()
+        if err != nil {
+                glog.Fatalf("Unable to retrieve database version. Error: %s", err)
+        }
+        glog.Infof("Current database version: %d", dbVersion)
+
+        if dbVersion < maxDBVersion {
+                glog.Infof("Migrating to version: %d", maxDBVersion)
+                err = vdb.Migrate(maxDBVersion)
+                if err != nil {
+                        glog.Fatalf("Unable to retrieve database version. Error: %s", err)
+                }
+        }
+
+        glog.Infoln("Database migration finished.")
+}