[gold] Add ignore rule migration logic.

Bug: skia:10582
Change-Id: I2d084e806ba2d85026e8cb5f1b5df3bca335b26e
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/353438
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
diff --git a/golden/cmd/fsmigrator/fsmigrator.go b/golden/cmd/fsmigrator/fsmigrator.go
new file mode 100644
index 0000000..16cacde
--- /dev/null
+++ b/golden/cmd/fsmigrator/fsmigrator.go
@@ -0,0 +1,95 @@
+// The fsmigrator executable migrates various data from firestore to an SQL database.
+// It uses port forwarding, as that is the simplest approach and there shouldn't be
+// too much data.
+package main
+
+import (
+	"context"
+	"flag"
+	"net/url"
+	"time"
+
+	"github.com/jackc/pgx/v4/pgxpool"
+
+	ifirestore "go.skia.org/infra/go/firestore"
+	"go.skia.org/infra/go/skerr"
+	"go.skia.org/infra/go/sklog"
+	"go.skia.org/infra/golden/go/ignore"
+	"go.skia.org/infra/golden/go/ignore/fs_ignorestore"
+	"go.skia.org/infra/golden/go/sql"
+)
+
+func main() {
+	var (
+		fsProjectID    = flag.String("fs_project_id", "skia-firestore", "The project with the firestore instance. Datastore and Firestore can't be in the same project.")
+		oldFSNamespace = flag.String("old_fs_namespace", "", "Typically the instance id. e.g. 'chrome-gpu', 'skia', etc")
+		newSQLDatabase = flag.String("new_sql_db", "", "Something like the instance id (no dashes)")
+	)
+	flag.Parse()
+
+	if *oldFSNamespace == "" {
+		sklog.Fatalf("You must include fs_namespace")
+	}
+
+	if *newSQLDatabase == "" {
+		sklog.Fatalf("You must include new_sql_db")
+	}
+
+	ctx := context.Background()
+	fsClient, err := ifirestore.NewClient(ctx, *fsProjectID, "gold", *oldFSNamespace, nil)
+	if err != nil {
+		sklog.Fatalf("Unable to configure Firestore: %s", err)
+	}
+
+	u := sql.GetConnectionURL("root@localhost:26234", *newSQLDatabase)
+	conf, err := pgxpool.ParseConfig(u)
+	if err != nil {
+		sklog.Fatalf("error getting postgres config %s: %s", u, err)
+	}
+	db, err := pgxpool.ConnectConfig(ctx, conf)
+	if err != nil {
+		sklog.Info("You must run\nkubectl port-forward gold-cockroachdb-0 26234:26234")
+		sklog.Fatalf("error connecting to the database: %s", err)
+	}
+
+	old := fs_ignorestore.New(ctx, fsClient)
+	var rules []ignore.Rule
+	// Wait for initial fetch to complete
+	for len(rules) == 0 {
+		time.Sleep(1000)
+		rules, err = old.List(ctx)
+		if err != nil {
+			sklog.Fatalf("Loading old rules: %s", err)
+		}
+	}
+
+	err = storeToSQL(ctx, db, rules)
+	if err != nil {
+		sklog.Fatalf("Error storing to SQL: %s", err)
+	}
+	sklog.Infof("Done")
+}
+
+func storeToSQL(ctx context.Context, db *pgxpool.Pool, rules []ignore.Rule) error {
+	if len(rules) == 0 {
+		return skerr.Fmt("Rules cannot be empty")
+	}
+	const statement = `INSERT INTO IgnoreRules (creator_email, updated_email, expires, note, query) VALUES `
+	const valuesPerRow = 5
+	placeholders := sql.ValuesPlaceholders(valuesPerRow, len(rules))
+	arguments := make([]interface{}, 0, valuesPerRow*len(rules))
+	for _, rule := range rules {
+		query, err := url.ParseQuery(rule.Query)
+		if err != nil {
+			// Hopefully never happens
+			return skerr.Wrapf(err, "invalid ignore query %q", rule.Query)
+		}
+		arguments = append(arguments, rule.CreatedBy, rule.UpdatedBy, rule.Expires, rule.Note, query)
+	}
+
+	_, err := db.Exec(ctx, statement+placeholders, arguments...)
+	if err != nil {
+		return skerr.Wrapf(err, "storing %d rules", len(rules))
+	}
+	return nil
+}