feat(BRIDGE-150): Observability service modification; user distinction utility & heartbeat; various observbility metrics & relevant integration tests

internal/services/observability/utils.go

@@ -0,0 +1,68 @@
+// Copyright (c) 2024 Proton AG
+//
+// This file is part of Proton Mail Bridge.
+//
+// Proton Mail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package observability
+
+import (
+	"strings"
+
+	"github.com/ProtonMail/proton-bridge/v3/internal/updater"
+)
+
+// settingsGetter - interface that maps to bridge object methods such that we
+// can pass the whole object instead of individual function callbacks.
+type settingsGetter interface {
+	GetCurrentUserAgent() string
+	GetProxyAllowed() bool
+	GetUpdateChannel() updater.Channel
+}
+
+// User agent mapping.
+const (
+	emailAgentAppleMail   = "apple_mail"
+	emailAgentOutlook     = "outlook"
+	emailAgentThunderbird = "thunderbird"
+	emailAgentOther       = "other"
+	emailAgentUnknown     = "unknown"
+)
+
+func matchUserAgent(userAgent string) string {
+	if userAgent == "" {
+		return emailAgentUnknown
+	}
+
+	userAgent = strings.ToLower(userAgent)
+	switch {
+	case strings.Contains(userAgent, "outlook"):
+		return emailAgentOutlook
+	case strings.Contains(userAgent, "thunderbird"):
+		return emailAgentThunderbird
+	case strings.Contains(userAgent, "mac") && strings.Contains(userAgent, "mail"):
+		return emailAgentAppleMail
+	case strings.Contains(userAgent, "mac") && strings.Contains(userAgent, "notes"):
+		return emailAgentUnknown
+	default:
+		return emailAgentOther
+	}
+}
+
+func getEnabled(value bool) string {
+	if !value {
+		return "disabled"
+	}
+	return "enabled"
+}