feat: add no publish handler

integration/watermill/gtag/messagehandler.go

@@ -8,7 +8,7 @@ import (
 	"github.com/pkg/errors"
 )
 
-func MessageHandler(handler func(payload *gtag.Payload, msg *message.Message) error) func(msg *message.Message) ([]*message.Message, error) {
+func MessageHandler(handler func(payload *gtag.Payload, msg *message.Message) error) message.HandlerFunc {
 	return func(msg *message.Message) ([]*message.Message, error) {
 		var payload *gtag.Payload
 

integration/watermill/gtag/nopublishmessagehandler.go

@@ -0,0 +1,23 @@
+package gtag
+
+import (
+	"encoding/json"
+
+	"github.com/ThreeDotsLabs/watermill/message"
+	"github.com/foomo/sesamy-go/pkg/encoding/gtag"
+	"github.com/pkg/errors"
+)
+
+func NoPublishMessageHandler(handler func(payload *gtag.Payload, msg *message.Message) error) func(msg *message.Message) error {
+	return func(msg *message.Message) error {
+		var payload *gtag.Payload
+
+		// unmarshal payload
+		if err := json.Unmarshal(msg.Payload, &payload); err != nil {
+			return errors.Wrap(err, "failed to unmarshal payload")
+		}
+
+		// handle payload
+		return handler(payload, msg)
+	}
+}

integration/watermill/mpv2/messagehandler.go

@@ -8,7 +8,7 @@ import (
 	"github.com/pkg/errors"
 )
 
-func MessageHandler(handler func(payload *mpv2.Payload[any], msg *message.Message) error) func(msg *message.Message) ([]*message.Message, error) {
+func MessageHandler(handler func(payload *mpv2.Payload[any], msg *message.Message) error) message.HandlerFunc {
 	return func(msg *message.Message) ([]*message.Message, error) {
 		var payload *mpv2.Payload[any]
 

integration/watermill/mpv2/nopublishmessagehandler.go

@@ -0,0 +1,23 @@
+package mpv2
+
+import (
+	"encoding/json"
+
+	"github.com/ThreeDotsLabs/watermill/message"
+	"github.com/foomo/sesamy-go/pkg/encoding/mpv2"
+	"github.com/pkg/errors"
+)
+
+func NoPublishMessageHandler(handler func(payload *mpv2.Payload[any], msg *message.Message) error) message.NoPublishHandlerFunc {
+	return func(msg *message.Message) error {
+		var payload *mpv2.Payload[any]
+
+		// unmarshal payload
+		if err := json.Unmarshal(msg.Payload, &payload); err != nil {
+			return errors.Wrap(err, "failed to unmarshal payload")
+		}
+
+		// handle payload
+		return handler(payload, msg)
+	}
+}