feat: inprogress

pkg/es/es.go

@@ -224,6 +224,10 @@ type PA[T any] interface {
 	event.Aggregate
 	*T
 }
+type PE[T any] interface {
+	event.Event
+	*T
+}
 
 // Create uses fn to create a new aggregate and store in db.
 func Create[A any, T PA[A]](ctx context.Context, es *EventStore, streamID string, fn func(context.Context, T) error) (agg T, err error) {
@@ -281,3 +285,30 @@ func Update[A any, T PA[A]](ctx context.Context, es *EventStore, streamID string
 
 	return
 }
+
+// Update uses fn to update an exsisting aggregate and store in db.
+func Upsert[A any, T PA[A]](ctx context.Context, es *EventStore, streamID string, fn func(context.Context, T) error) (agg T, err error) {
+	ctx, span := logz.Span(ctx)
+	defer span.End()
+
+	agg = new(A)
+	agg.SetStreamID(streamID)
+
+	if err = es.Load(ctx, agg); err != nil {
+		return
+	}
+
+	if err = fn(ctx, agg); err != nil {
+		return
+	}
+
+	if err = event.ShouldExist(agg); err != nil {
+		return
+	}
+
+	if _, err = es.Save(ctx, agg); err != nil {
+		return
+	}
+
+	return
+}

pkg/es/es.graphqls

@@ -4,4 +4,20 @@ type Meta @goModel(model: "github.com/sour-is/ev/pkg/es/event.Meta") {
     streamID: String!
     created: Time!
     position: Int!
+}
+
+extend type Query {
+    events(streamID: String! paging: PageInput): Connection!
+}
+extend type Subscription {
+    """after == 0 start from begining, after == -1 start from end"""
+    eventAdded(streamID: String! after: Int! = -1): Event
+}
+
+type Event implements Edge {
+    id: ID!
+
+    eventID: String!
+    values: Map!
+    eventMeta: Meta!
 }

pkg/es/event/aggregate.go

@@ -29,16 +29,16 @@ func Append(a Aggregate, lis ...Event) {
 
 // NotExists returns error if there are no events present.
 func NotExists(a Aggregate) error {
-	if a.StreamVersion() != 0 {
-		return fmt.Errorf("%w, got version == %d", ErrShouldNotExist, a.StreamVersion())
+	if a.Version() != 0 {
+		return fmt.Errorf("%w, got version == %d", ErrShouldNotExist, a.Version())
 	}
 	return nil
 }
 
 // ShouldExists returns error if there are no events present.
 func ShouldExist(a Aggregate) error {
-	if a.StreamVersion() == 0 {
-		return fmt.Errorf("%w, got version == %d", ErrShouldExist, a.StreamVersion())
+	if a.Version() == 0 {
+		return fmt.Errorf("%w, got version == %d", ErrShouldExist, a.Version())
 	}
 	return nil
 }

pkg/es/event/reflect.go

@@ -246,3 +246,12 @@ func embedJSON(s string) json.RawMessage {
 	}
 	return []byte(fmt.Sprintf(`"%s"`, strings.Replace(s, `"`, `\"`, -1)))
 }
+
+func values(e Event) map[string]any {
+	m := make(map[string]any)
+	v := reflect.ValueOf(e)
+	for _, idx := range reflect.VisibleFields(v) {
+		field := v.FieldByIndex(idx.Index)
+		m[field.]
+	}
+}