[MM-54288] Support Packet V2 (#29403)

server/public/utils/timeutils/time.go

@@ -0,0 +1,29 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package timeutils
+
+import (
+	"time"
+)
+
+const (
+	RFC3339Milli = "2006-01-02T15:04:05.999Z07:00"
+)
+
+func FormatMillis(millis int64) string {
+	return time.UnixMilli(millis).Format(RFC3339Milli)
+}
+
+func ParseFormatedMillis(s string) (millis int64, err error) {
+	if s == "" {
+		return 0, nil
+	}
+
+	t, err := time.Parse(RFC3339Milli, s)
+	if err != nil {
+		return 0, err
+	}
+
+	return t.UnixMilli(), nil
+}

server/public/utils/timeutils/time_test.go

@@ -0,0 +1,57 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package timeutils
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFormatMillis(t *testing.T) {
+	t.Run("zero time", func(t *testing.T) {
+		result := FormatMillis(0)
+		// The concrete time depends on the timezone, so we can't test the exact time
+		assert.Contains(t, result, "1970-01-01")
+		assert.Contains(t, result, "00:00")
+	})
+
+	t.Run("positive time", func(t *testing.T) {
+		result := FormatMillis(1609459200000) // 2021-01-01 00:00:00 UTC
+		assert.Contains(t, result, "2021-01-01")
+		assert.Contains(t, result, "00:00")
+	})
+
+	t.Run("negative time", func(t *testing.T) {
+		result := FormatMillis(-1609459200000) // 1919-01-01 00:00:00 UTC
+		assert.Contains(t, result, "1919-01-01")
+		assert.Contains(t, result, "00:00")
+	})
+}
+
+func TestParseFormatedMillis(t *testing.T) {
+	t.Run("empty string", func(t *testing.T) {
+		result, err := ParseFormatedMillis("")
+		assert.NoError(t, err)
+		assert.Equal(t, int64(0), result)
+	})
+
+	t.Run("valid timestamp", func(t *testing.T) {
+		result, err := ParseFormatedMillis("2021-01-01T00:00:00.000Z")
+		assert.NoError(t, err)
+		assert.Equal(t, int64(1609459200000), result)
+	})
+
+	t.Run("invalid format", func(t *testing.T) {
+		result, err := ParseFormatedMillis("2021-01-01")
+		assert.Error(t, err)
+		assert.Equal(t, int64(0), result)
+	})
+
+	t.Run("invalid date", func(t *testing.T) {
+		result, err := ParseFormatedMillis("2021-13-01T00:00:00.000Z")
+		assert.Error(t, err)
+		assert.Equal(t, int64(0), result)
+	})
+}