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

internal/services/observability/heartbeat.go

@@ -0,0 +1,119 @@
+// 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 (
+	"fmt"
+	"time"
+
+	"github.com/ProtonMail/gluon/async"
+	"github.com/ProtonMail/go-proton-api"
+)
+
+const genericHeartbeatSchemaName = "bridge_generic_user_heartbeat_total"
+
+type heartbeatData struct {
+	receivedSyncError      bool
+	receivedEventLoopError bool
+	receivedOtherError     bool
+}
+
+func (d *distinctionUtility) resetHeartbeatData() {
+	d.heartbeatData.receivedSyncError = false
+	d.heartbeatData.receivedOtherError = false
+	d.heartbeatData.receivedEventLoopError = false
+}
+
+func (d *distinctionUtility) updateHeartbeatData(errType DistinctionErrorTypeEnum) {
+	d.withUpdateHeartbeatDataLock(func() {
+		switch errType {
+		case SyncError:
+			d.heartbeatData.receivedSyncError = true
+		case EventLoopError:
+			d.heartbeatData.receivedEventLoopError = true
+		}
+	})
+}
+
+func (d *distinctionUtility) runHeartbeat() {
+	go func() {
+		defer async.HandlePanic(d.panicHandler)
+		defer d.heartbeatTicker.Stop()
+
+		for {
+			select {
+			case <-d.ctx.Done():
+				return
+			case <-d.heartbeatTicker.C:
+				d.sendHeartbeat()
+			}
+		}
+	}()
+}
+
+func (d *distinctionUtility) withUpdateHeartbeatDataLock(fn func()) {
+	d.heartbeatDataLock.Lock()
+	defer d.heartbeatDataLock.Unlock()
+	fn()
+}
+
+// sendHeartbeat - will only send a heartbeat if there is an authenticated client
+// otherwise we might end up polluting the cache and therefore our metrics.
+func (d *distinctionUtility) sendHeartbeat() {
+	d.withUpdateHeartbeatDataLock(func() {
+		d.sendMetricsWithGuard(d.generateHeartbeatUserMetric())
+		d.resetHeartbeatData()
+	})
+}
+
+func formatBool(value bool) string {
+	return fmt.Sprintf("%t", value)
+}
+
+// generateHeartbeatUserMetric creates the heartbeat user metric and includes the relevant data.
+func (d *distinctionUtility) generateHeartbeatUserMetric() proton.ObservabilityMetric {
+	return generateHeartbeatMetric(
+		d.getUserPlanSafe(),
+		d.getEmailClientUserAgent(),
+		getEnabled(d.settingsGetter.GetProxyAllowed()),
+		getEnabled(d.getBetaAccessEnabled()),
+		formatBool(d.heartbeatData.receivedOtherError),
+		formatBool(d.heartbeatData.receivedSyncError),
+		formatBool(d.heartbeatData.receivedEventLoopError),
+	)
+}
+
+func generateHeartbeatMetric(plan, mailClient, dohEnabled, betaAccess, otherError, syncError, eventLoopError string) proton.ObservabilityMetric {
+	return proton.ObservabilityMetric{
+		Name:      genericHeartbeatSchemaName,
+		Version:   1,
+		Timestamp: time.Now().Unix(),
+		Data: map[string]interface{}{
+			"Value": 1,
+			"Labels": map[string]string{
+				"plan":                   plan,
+				"mailClient":             mailClient,
+				"dohEnabled":             dohEnabled,
+				"betaAccessEnabled":      betaAccess,
+				"receivedOtherError":     otherError,
+				"receivedSyncError":      syncError,
+				"receivedEventLoopError": eventLoopError,
+			},
+		},
+	}
+}