feat(storage): read only transactions for queries (#6415)

* fix: tests

* bastle wie en grosse

* fix(database): scan as callback

* fix tests

* fix merge failures

* remove as of system time

* refactor: remove unused test

* refacotr: remove unused lines

internal/database/cockroach/config.go

@@ -2,7 +2,6 @@ package cockroach
 
 import (
 	"database/sql"
-	"fmt"
 	"strconv"
 	"strings"
 	"time"
@@ -94,12 +93,7 @@ func (c *Config) Type() string {
 }
 
 func (c *Config) Timetravel(d time.Duration) string {
-	// verify that it is at least 1 micro second
-	if d < time.Microsecond {
-		d = time.Microsecond
-	}
-
-	return fmt.Sprintf(" AS OF SYSTEM TIME '-%d µs' ", d.Microseconds())
+	return ""
 }
 
 type User struct {

internal/database/cockroach/config_test.go

@@ -1,61 +0,0 @@
-package cockroach
-
-import (
-	"testing"
-	"time"
-)
-
-func TestConfig_Timetravel(t *testing.T) {
-	type args struct {
-		d time.Duration
-	}
-	tests := []struct {
-		name string
-		args args
-		want string
-	}{
-		{
-			name: "no duration",
-			args: args{
-				d: 0,
-			},
-			want: " AS OF SYSTEM TIME '-1 µs' ",
-		},
-		{
-			name: "less than microsecond",
-			args: args{
-				d: 100 * time.Nanosecond,
-			},
-			want: " AS OF SYSTEM TIME '-1 µs' ",
-		},
-		{
-			name: "10 microseconds",
-			args: args{
-				d: 10 * time.Microsecond,
-			},
-			want: " AS OF SYSTEM TIME '-10 µs' ",
-		},
-		{
-			name: "10 milliseconds",
-			args: args{
-				d: 10 * time.Millisecond,
-			},
-			want: " AS OF SYSTEM TIME '-10000 µs' ",
-		},
-		{
-			name: "1 second",
-			args: args{
-				d: 1 * time.Second,
-			},
-			want: " AS OF SYSTEM TIME '-1000000 µs' ",
-		},
-	}
-	for _, tt := range tests {
-		c := &Config{}
-		t.Run(tt.name, func(t *testing.T) {
-			if got := c.Timetravel(tt.args.d); got != tt.want {
-				t.Errorf("Config.Timetravel() = %q, want %q", got, tt.want)
-			}
-		})
-	}
-}

internal/database/database.go

@@ -1,9 +1,12 @@
 package database
 
 import (
+	"context"
 	"database/sql"
 	"reflect"
 
+	"github.com/zitadel/logging"
+
 	_ "github.com/zitadel/zitadel/internal/database/cockroach"
 	"github.com/zitadel/zitadel/internal/database/dialect"
 	_ "github.com/zitadel/zitadel/internal/database/postgres"
@@ -24,6 +27,66 @@ type DB struct {
 	dialect.Database
 }
 
+func (db *DB) Query(scan func(*sql.Rows) error, query string, args ...any) error {
+	return db.QueryContext(context.Background(), scan, query, args...)
+}
+
+func (db *DB) QueryContext(ctx context.Context, scan func(rows *sql.Rows) error, query string, args ...any) (err error) {
+	tx, err := db.BeginTx(ctx, &sql.TxOptions{ReadOnly: true})
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if err != nil {
+			rollbackErr := tx.Rollback()
+			logging.OnError(rollbackErr).Info("commit of read only transaction failed")
+			return
+		}
+		err = tx.Commit()
+	}()
+
+	rows, err := tx.QueryContext(ctx, query, args...)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		closeErr := rows.Close()
+		logging.OnError(closeErr).Info("rows.Close failed")
+	}()
+
+	if err = scan(rows); err != nil {
+		return err
+	}
+	return rows.Err()
+}
+
+func (db *DB) QueryRow(scan func(*sql.Row) error, query string, args ...any) (err error) {
+	return db.QueryRowContext(context.Background(), scan, query, args...)
+}
+
+func (db *DB) QueryRowContext(ctx context.Context, scan func(row *sql.Row) error, query string, args ...any) (err error) {
+	tx, err := db.BeginTx(ctx, &sql.TxOptions{ReadOnly: true})
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if err != nil {
+			rollbackErr := tx.Rollback()
+			logging.OnError(rollbackErr).Info("commit of read only transaction failed")
+			return
+		}
+		err = tx.Commit()
+	}()
+
+	row := tx.QueryRowContext(ctx, query, args...)
+
+	err = scan(row)
+	if err != nil {
+		return err
+	}
+	return row.Err()
+}
+
 func Connect(config Config, useAdmin bool) (*DB, error) {
 	client, err := config.connector.Connect(useAdmin)
 	if err != nil {