feat: opentelemetry for tracing and metrics

api/gql_ev/resolver.go

@@ -5,24 +5,47 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/sour-is/ev/internal/logz"
 	"github.com/sour-is/ev/pkg/es"
 	"github.com/sour-is/ev/pkg/msgbus"
+	"go.opentelemetry.io/otel/metric/instrument/syncint64"
+	"go.uber.org/multierr"
 )
 
-// This file will not be regenerated automatically.
-//
-// It serves as dependency injection for your app, add any dependencies you require here.
-
 type Resolver struct {
 	es *es.EventStore
+
+	Mresolver_posts            syncint64.Counter
+	Mresolver_post_added       syncint64.Counter
+	Mresolver_post_added_event syncint64.Counter
 }
 
-func New(es *es.EventStore) *Resolver {
-	return &Resolver{es}
+func New(es *es.EventStore) (*Resolver, error) {
+	m := logz.Meter(context.Background())
+
+	var errs error
+
+	Mresolver_posts, err := m.SyncInt64().Counter("resolver_posts")
+	errs = multierr.Append(errs, err)
+
+	Mresolver_post_added, err := m.SyncInt64().Counter("resolver_post_added")
+	errs = multierr.Append(errs, err)
+
+	Mresolver_post_added_event, err := m.SyncInt64().Counter("resolver_post_added")
+	errs = multierr.Append(errs, err)
+
+	return &Resolver{
+		es,
+		Mresolver_posts,
+		Mresolver_post_added,
+		Mresolver_post_added_event,
+	}, errs
 }
 
 // Posts is the resolver for the events field.
 func (r *Resolver) Posts(ctx context.Context, streamID string, paging *PageInput) (*Connection, error) {
+	r.Mresolver_posts.Add(ctx, 1)
+
 	lis, err := r.es.Read(ctx, streamID, paging.GetIdx(0), paging.GetCount(30))
 	if err != nil {
 		return nil, err
@@ -66,6 +89,8 @@ func (r *Resolver) Posts(ctx context.Context, streamID string, paging *PageInput
 }
 
 func (r *Resolver) PostAdded(ctx context.Context, streamID string, after int64) (<-chan *PostEvent, error) {
+	r.Mresolver_post_added.Add(ctx, 1)
+
 	es := r.es.EventStream()
 	if es == nil {
 		return nil, fmt.Errorf("EventStore does not implement streaming")
@@ -90,6 +115,8 @@ func (r *Resolver) PostAdded(ctx context.Context, streamID string, after int64)
 			if err != nil {
 				break
 			}
+			r.Mresolver_post_added_event.Add(ctx, int64(len(events)))
+
 			for _, e := range events {
 				m := e.EventMeta()
 				if p, ok := e.(*msgbus.PostEvent); ok {