Observability

Observability

Metrics (Micrometer + Prometheus)

All metrics are exposed at /actuator/prometheus.

Application Metrics

Metric	Type	Tags
syncflow.snapshot.duration	Timer	pipeline
syncflow.snapshot.rows	Counter	pipeline
syncflow.snapshot.errors	Counter	pipeline
syncflow.cdc.events	Counter	pipeline, table
syncflow.cdc.lag	Gauge	pipeline
syncflow.sync.duration	Timer	pipeline
syncflow.sync.events	Counter	pipeline
syncflow.sync.errors	Counter	pipeline
syncflow.dlq.count	Gauge	pipeline

Infrastructure Metrics

• JVM metrics (heap, GC, threads)
• HikariCP metrics (connections, pool usage)
• Tomcat metrics (requests, threads)
• Spring MVC metrics

Custom Tags

All metrics include application: syncflow tag (configurable via management.metrics.tags.application).

Distributed Tracing (OpenTelemetry)

Traces are exported to OTLP endpoint:

management:
  otlp:
    tracing:
      endpoint: http://localhost:4318/v1/traces

Trace Propagation

• MDC integration: traceId, correlationId, pipelineId in all log lines
• HTTP header propagation for inter-service calls
• Debezium engine traces

Log Pattern

%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] [%X{traceId}] [%X{correlationId}] [%X{pipelineId}] %-5level %logger{36} - %msg%n

Dashboards (Grafana)

Pre-configured dashboards in docker/grafana/:

Dashboard	Panels
Overview	Pipeline status, connection health, active captures
CDC	Event throughput, lag, error rate
Snapshot	Progress, duration, rows processed
System	JVM, CPU, memory, connections

Health Checks

# Basic health
GET /api/health

# Detailed with connector status
GET /api/health?show-details=always

# Kubernetes probes
GET /actuator/health/liveness
GET /actuator/health/readiness

Diagnostics

Endpoint	Description
GET /api/diagnostics/system	JVM/OS/Java info
GET /api/diagnostics/connectors	Connector health + latency
GET /api/diagnostics/pipelines	Pipeline status + metrics
GET /api/diagnostics/executions	Recent execution history

Alerting

Prometheus alerting rules in k8s/base/prometheusrule.yaml:

• High error rate (> 1% of events)
• CDC lag exceeding threshold (> 30s)
• Snapshot duration exceeding SLA (> 1h)
• DLQ depth growing
• Agent offline
• Memory usage > 80%

SSE (Server-Sent Events)

Live progress streaming for snapshots:

GET /api/snapshots/{id}/events

Events:

• snapshot-status — Progress updates (batches, rows, percentage)
• snapshot-complete — Terminal state (COMPLETED/CANCELLED/FAILED)