fix: add events.go back

Author: pan93412

graph/ent.resolvers.go

@@ -0,0 +1,133 @@
+package events
+
+import (
+	"context"
+	"log/slog"
+	"strconv"
+	"time"
+
+	"github.com/database-playground/backend-v2/ent"
+	"github.com/database-playground/backend-v2/internal/metrics"
+	"github.com/posthog/posthog-go"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	otelcodes "go.opentelemetry.io/otel/codes"
+	"go.opentelemetry.io/otel/trace"
+)
+
+var tracer = otel.Tracer("dbplay.events")
+
+// EventService is the service for triggering events.
+type EventService struct {
+	entClient     *ent.Client
+	posthogClient posthog.Client
+
+	handlers []EventHandler
+}
+
+// NewEventService creates a new EventService.
+func NewEventService(entClient *ent.Client, posthogClient posthog.Client) *EventService {
+	return &EventService{
+		entClient:     entClient,
+		posthogClient: posthogClient,
+		handlers:      []EventHandler{NewPointsGranter(entClient, posthogClient)},
+	}
+}
+
+// Event is the event to be triggered.
+type Event struct {
+	Type    EventType
+	Payload map[string]any
+	UserID  int
+}
+
+// EventHandler is the handler for the event.
+//
+// You can think it as the callback of the event.
+type EventHandler interface {
+	HandleEvent(ctx context.Context, event *ent.Event) error
+}
+
+// TriggerEvent triggers an event.
+func (s *EventService) TriggerEvent(ctx context.Context, event Event) {
+	ctx, span := tracer.Start(ctx, "TriggerEvent",
+		trace.WithAttributes(
+			attribute.String("event.type", string(event.Type)),
+			attribute.Int("user.id", event.UserID),
+		))
+	defer span.End()
+
+	err := s.triggerEvent(ctx, event)
+	if err != nil {
+		span.SetStatus(otelcodes.Error, "Failed to trigger event")
+		span.RecordError(err)
+		slog.Error("failed to trigger event", "error", err)
+	} else {
+		span.SetStatus(otelcodes.Ok, "Event triggered successfully")
+	}
+
+	if s.posthogClient != nil {
+		span.AddEvent("posthog.send", trace.WithAttributes(
+			attribute.String("event.type", string(event.Type)),
+			attribute.Int("user.id", event.UserID),
+		))
+		slog.Debug("sending event to PostHog", "event_type", event.Type, "user_id", event.UserID)
+		err = s.posthogClient.Enqueue(posthog.Capture{
+			DistinctId: strconv.Itoa(event.UserID),
+			Event:      string(event.Type),
+			Timestamp:  time.Now(),
+			Properties: event.Payload,
+		})
+		if err != nil {
+			span.RecordError(err)
+			slog.Error("failed to send event to PostHog", "error", err)
+		}
+	}
+}
+
+// triggerEvent triggers an event synchronously.
+func (s *EventService) triggerEvent(ctx context.Context, event Event) error {
+	ctx, span := tracer.Start(ctx, "triggerEvent",
+		trace.WithAttributes(
+			attribute.String("event.type", string(event.Type)),
+			attribute.Int("user.id", event.UserID),
+		))
+	defer span.End()
+
+	span.AddEvent("database.event.create")
+	eventEntity, err := s.entClient.Event.Create().
+		SetType(string(event.Type)).
+		SetPayload(event.Payload).
+		SetUserID(event.UserID).
+		SetTriggeredAt(time.Now()).
+		Save(ctx)
+	if err != nil {
+		span.SetStatus(otelcodes.Error, "Failed to create event")
+		span.RecordError(err)
+		return err
+	}
+
+	span.SetAttributes(attribute.Int("event.id", eventEntity.ID))
+
+	// Record metrics
+	metrics.RecordEvent(string(event.Type))
+
+	span.AddEvent("handlers.processing", trace.WithAttributes(
+		attribute.Int("handlers.count", len(s.handlers)),
+	))
+
+	for i, handler := range s.handlers {
+		span.AddEvent("handler.executing", trace.WithAttributes(
+			attribute.Int("handler.index", i),
+		))
+		err := handler.HandleEvent(ctx, eventEntity)
+		if err != nil {
+			span.SetStatus(otelcodes.Error, "Failed to handle event")
+			span.RecordError(err)
+			return err
+		}
+	}
+
+	span.SetStatus(otelcodes.Ok, "Event triggered successfully")
+	return nil
+}