satellite/satellitedb: add utility for converting slices

Change-Id: I2654a9ef7c58016bd5af923c66f5f31819ab9b9d

satellite/satellitedb/database.go

@@ -398,13 +398,3 @@ func (dbc *satelliteDBCollectionTesting) ProductionMigration() *migrate.Migratio
 func (dbc *satelliteDBCollectionTesting) TestMigration() *migrate.Migration {
 	return dbc.getByName("").TestMigration()
 }
-
-func withRows(rows tagsql.Rows, err error) func(func(tagsql.Rows) error) error {
-	return func(callback func(tagsql.Rows) error) error {
-		if err != nil {
-			return err
-		}
-		err := callback(rows)
-		return errs.Combine(rows.Err(), rows.Close(), err)
-	}
-}

satellite/satellitedb/util.go

@@ -0,0 +1,36 @@
+// Copyright (C) 2023 Storj Labs, Inc.
+// See LICENSE for copying information.
+
+package satellitedb
+
+import (
+	"github.com/zeebo/errs"
+
+	"storj.io/private/tagsql"
+)
+
+// withRows ensures that rows get properly closed after the callback finishes.
+func withRows(rows tagsql.Rows, err error) func(func(tagsql.Rows) error) error {
+	return func(callback func(tagsql.Rows) error) error {
+		if err != nil {
+			return err
+		}
+		err := callback(rows)
+		return errs.Combine(rows.Err(), rows.Close(), err)
+	}
+}
+
+// convertSlice converts xs by applying fn to each element.
+// If there's an error during conversion, the function
+// returns an empty slice and the error.
+func convertSlice[In, Out any](xs []In, fn func(In) (Out, error)) ([]Out, error) {
+	rs := make([]Out, len(xs))
+	for i := range xs {
+		var err error
+		rs[i], err = fn(xs[i])
+		if err != nil {
+			return nil, err
+		}
+	}
+	return rs, nil
+}

satellite/satellitedb/util_test.go

@@ -0,0 +1,23 @@
+// Copyright (C) 2023 Storj Labs, Inc.
+// See LICENSE for copying information.
+
+package satellitedb
+
+import (
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestConvertSlice(t *testing.T) {
+	good := []string{"1", "2", "3", "4"}
+	out, err := convertSlice(good, strconv.Atoi)
+	require.NoError(t, err)
+	require.Equal(t, []int{1, 2, 3, 4}, out)
+
+	bad := []string{"1", "bad", "asdf", ""}
+	out, err = convertSlice(bad, strconv.Atoi)
+	require.Error(t, err)
+	require.Nil(t, out)
+}