Refactored Request/Reply and removed reflect dependency

ella-to · May 18, 2024 · dbee65e · dbee65e
1 parent b30e446
commit dbee65e
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Showing 4 changed files with 31 additions and 40 deletions.
diff --git a/examples/request-reply-single/main.go b/examples/request-reply-single/main.go
@@ -44,11 +44,12 @@ func main() {
 		return &Resp{Result: req.A / req.B}, nil
 	})
 
-	fn := bus.Request[*Req, *Resp](c, funcName)
+	fn := bus.Request(c, funcName)
 
 	for range 1000 {
 		req := &Req{A: 4, B: 2}
-		resp, err := fn(ctx, req)
+		resp := &Resp{}
+		err := fn(ctx, req, resp)
 		if err != nil {
 			fmt.Printf("%s = %s\n", req, err)
 		} else {

diff --git a/examples/request-reply/request/main.go b/examples/request-reply/request/main.go
@@ -19,11 +19,12 @@ func main() {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
-	fn := bus.Request[*data.Req, *data.Resp](c, "func.div")
+	fn := bus.Request(c, "func.div")
 
 	for range 1000 {
 		req := &data.Req{A: 4, B: 2}
-		resp, err := fn(ctx, req)
+		resp := &data.Resp{}
+		err := fn(ctx, req, resp)
 		if err != nil {
 			fmt.Printf("%s = %s\n", req, err)
 		} else {

diff --git a/request_reply.go b/request_reply.go
@@ -5,27 +5,27 @@ import (
 	"encoding/json"
 	"fmt"
 	"log/slog"
-	"reflect"
 	"time"
 )
 
-type RequestReplyFunc[Req, Resp any] func(context.Context, Req) (Resp, error)
+type RequestFunc func(ctx context.Context, req any, resp any) error
+type ReplyFunc[Req, Resp any] func(ctx context.Context, req Req) (Resp, error)
 
-func Request[Req, Resp any](stream Stream, subject string) RequestReplyFunc[Req, Resp] {
-	return func(ctx context.Context, req Req) (resp Resp, err error) {
+func Request(stream Stream, subject string) RequestFunc {
+	return func(ctx context.Context, req any, resp any) (err error) {
 		evt, err := NewEvent(
 			WithSubject(subject),
 			WithReply(),
 			WithJsonData(req),
 			WithExpiresAt(30*time.Second),
 		)
 		if err != nil {
-			return resp, err
+			return err
 		}
 
 		err = stream.Put(ctx, evt)
 		if err != nil {
-			return resp, err
+			return err
 		}
 
 		for msgs, err := range stream.Get(
@@ -34,11 +34,11 @@ func Request[Req, Resp any](stream Stream, subject string) RequestReplyFunc[Req,
 			WithFromOldest(),
 		) {
 			if err != nil {
-				return resp, err
+				return err
 			}
 
 			if len(msgs.Events) != 1 {
-				return resp, fmt.Errorf("expected one event")
+				return fmt.Errorf("expected one event but got %d", len(msgs.Events))
 			}
 
 			evt := msgs.Events[0]
@@ -50,31 +50,31 @@ func Request[Req, Resp any](stream Stream, subject string) RequestReplyFunc[Req,
 
 			err = json.Unmarshal(evt.Data, &replyMsg)
 			if err != nil {
-				return resp, err
+				return err
 			}
 
 			if replyMsg.Type == "error" {
 				var errMsg string
 				err = json.Unmarshal(replyMsg.Payload, &errMsg)
 				if err != nil {
-					return resp, err
+					return err
 				}
-				return resp, fmt.Errorf(errMsg)
+				return fmt.Errorf(errMsg)
 			}
 
-			resp, err = jsonUnmarshal[Resp](replyMsg.Payload)
+			err = json.Unmarshal(replyMsg.Payload, resp)
 			if err != nil {
-				return resp, err
+				return err
 			}
 
-			return resp, nil
+			return nil
 		}
 
 		return
 	}
 }
 
-func Reply[Req, Resp any](ctx context.Context, stream Stream, subject string, fn RequestReplyFunc[Req, Resp]) {
+func Reply[Req, Resp any](ctx context.Context, stream Stream, subject string, fn ReplyFunc[*Req, *Resp]) {
 	queueName := fmt.Sprintf("queue.%s", subject)
 	msgs := stream.Get(
 		ctx,
@@ -97,7 +97,8 @@ func Reply[Req, Resp any](ctx context.Context, stream Stream, subject string, fn
 
 			event := msg.Events[0]
 
-			req, err := jsonUnmarshal[Req](event.Data)
+			var req Req
+			err = json.Unmarshal(event.Data, &req)
 			if err != nil {
 				return
 			}
@@ -107,7 +108,7 @@ func Reply[Req, Resp any](ctx context.Context, stream Stream, subject string, fn
 				Payload any    `json:"payload"`
 			}
 
-			resp, err := fn(ctx, req)
+			resp, err := fn(ctx, &req)
 			if err != nil {
 				replyMsg.Type = "error"
 				replyMsg.Payload = err.Error()
@@ -133,17 +134,3 @@ func Reply[Req, Resp any](ctx context.Context, stream Stream, subject string, fn
 		}
 	}()
 }
-
-func jsonUnmarshal[T any](data json.RawMessage) (v T, err error) {
-	v = initializePointer(v)
-	err = json.Unmarshal(data, &v)
-	return v, err
-}
-
-func initializePointer[T any](v T) T {
-	t := reflect.TypeOf(v)
-	if t.Kind() != reflect.Ptr {
-		return v
-	}
-	return reflect.New(t.Elem()).Interface().(T)
-}
diff --git a/request_reply_test.go b/request_reply_test.go
@@ -21,24 +21,26 @@ func TestRequestReply(t *testing.T) {
 		Result int
 	}
 
-	bus.Reply(context.TODO(), client, "func.div", func(ctx context.Context, req *Req) (*Resp, error) {
+	bus.Reply(context.TODO(), client, "func.div", func(ctx context.Context, req *Req) (resp *Resp, err error) {
 		if req.B == 0 {
 			return nil, fmt.Errorf("division by zero")
 		}
 
 		return &Resp{Result: req.A / req.B}, nil
 	})
 
-	fn := bus.Request[*Req, *Resp](client, "func.div")
+	fn := bus.Request(client, "func.div")
 
 	req := &Req{A: 4, B: 2}
-	resp, err := fn(context.Background(), req)
+	resp := &Resp{}
+	err := fn(context.Background(), req, resp)
+
 	assert.NoError(t, err)
 	assert.Equal(t, 2, resp.Result)
 
 	req = &Req{A: 4, B: 0}
-	resp, err = fn(context.Background(), req)
+	resp = &Resp{}
+	err = fn(context.Background(), req, resp)
 	assert.Error(t, err)
 	assert.Equal(t, "division by zero", err.Error())
-	assert.Nil(t, resp)
 }