better handler registration and dispatch

v2/context.go

@@ -2,10 +2,11 @@ package serverevents
 
 import (
 	gocontext "context"
-	di "git.apihub24.de/admin/generic-di"
-	"github.com/coder/websocket"
 	"sync"
 	"time"
+
+	di "git.apihub24.de/admin/generic-di"
+	"github.com/coder/websocket"
 )
 
 func init() {
@@ -21,7 +22,7 @@ type IContext interface {
 	Get(key string) (any, bool)
 	RemoveMetaData(key string)
 	CleanupIn(lifetime time.Duration)
-	Dispatch(eventName string, data any, filter func(c IContext) bool)
+	Dispatch(event IEvent, filter func(c IContext) bool)
 	IsCaller(c IContext) bool
 }
 
@@ -84,9 +85,7 @@ func (context *context) RemoveMetaData(key string) {
 	context.mutex.Lock()
 	defer context.mutex.Unlock()
 
-	if _, ok := context.metadata[key]; ok {
+	delete(context.metadata, key)
-		delete(context.metadata, key)
-	}
 }
 
 func (context *context) CleanupIn(lifetime time.Duration) {
@@ -110,10 +109,10 @@ func (context *context) CleanupIn(lifetime time.Duration) {
 	}(context.id)
 }
 
-func (context *context) Dispatch(eventName string, data any, filter func(c IContext) bool) {
+func (context *context) Dispatch(event IEvent, filter func(c IContext) bool) {
 	ev := Event{
-		Type:          eventName,
+		Type:          event.GetEventName(),
-		Data:          data,
+		Data:          event.GetEventData(),
 		IsBackendOnly: filter == nil,
 		Filter:        filter,
 	}

v2/event.go

@@ -6,3 +6,8 @@ type Event struct {
 	IsBackendOnly bool                  `json:"-"`
 	Filter        func(c IContext) bool `json:"-"`
 }
+
+type IEvent interface {
+	GetEventName() string
+	GetEventData() any
+}

v2/handler.go

@@ -1,6 +1,7 @@
 package serverevents
 
 type IEventHandler interface {
+	GetConnectedEventName() string
 	CanExecute(IContext) bool
 	Handle(IContext, any)
 }

v2/implementation_test/data/dto/greeting.go

@@ -0,0 +1,5 @@
+package dto
+
+type Greeting struct {
+	Message string `json:"message"`
+}

v2/implementation_test/events/definitions/greet_event.go

@@ -0,0 +1,26 @@
+package definitions
+
+import (
+	serverevents "git.apihub24.de/admin/server_events/v2"
+	"git.apihub24.de/admin/server_events/v2/implementation_test/data/dto"
+)
+
+const GreeterEventName = "greet"
+
+type greetEvent struct {
+	data dto.Greeting
+}
+
+func NewGreetEvent(data dto.Greeting) serverevents.IEvent {
+	return &greetEvent{
+		data: data,
+	}
+}
+
+func (ev *greetEvent) GetEventName() string {
+	return GreeterEventName
+}
+
+func (ev *greetEvent) GetEventData() any {
+	return ev.data
+}

v2/implementation_test/events/definitions/greet_me_event.go

@@ -0,0 +1,23 @@
+package definitions
+
+import serverevents "git.apihub24.de/admin/server_events/v2"
+
+const GreetMeEventName = "greet me"
+
+type greetMeEvent struct {
+	data string
+}
+
+func NewGreetMeEvent(name string) serverevents.IEvent {
+	return &greetMeEvent{
+		data: name,
+	}
+}
+
+func (ev *greetMeEvent) GetEventName() string {
+	return GreetMeEventName
+}
+
+func (ev *greetMeEvent) GetEventData() any {
+	return ev.data
+}

v2/implementation_test/events/definitions/ping_event.go

@@ -0,0 +1,19 @@
+package definitions
+
+import serverevents "git.apihub24.de/admin/server_events/v2"
+
+const PingEventName = "ping"
+
+type pingEvent struct{}
+
+func NewPingEvent() serverevents.IEvent {
+	return &pingEvent{}
+}
+
+func (ev *pingEvent) GetEventName() string {
+	return PingEventName
+}
+
+func (ev *pingEvent) GetEventData() any {
+	return nil
+}

v2/implementation_test/events/definitions/pong_event.go

@@ -0,0 +1,19 @@
+package definitions
+
+import serverevents "git.apihub24.de/admin/server_events/v2"
+
+const PongEventName = "pong"
+
+type pongEvent struct{}
+
+func NewPongEvent() serverevents.IEvent {
+	return &pongEvent{}
+}
+
+func (ev *pongEvent) GetEventName() string {
+	return PongEventName
+}
+
+func (ev *pongEvent) GetEventData() any {
+	return nil
+}

v2/implementation_test/events/greeter.go

@@ -1,39 +0,0 @@
-package events
-
-import (
-	"fmt"
-	serverevents "git.apihub24.de/admin/server_events/v2"
-)
-
-func withSameUserName(context serverevents.IContext) func(context serverevents.IContext) bool {
-	return serverevents.CreateMetaDataFilter(context, func(c serverevents.IContext) string {
-		userName, _ := serverevents.MetadataAs[string](context, "UserName")
-		return userName
-	}, func(a string, b string) bool {
-		return a == b
-	})
-}
-
-type greeting struct {
-	Message string
-}
-
-type greeterEventHandler struct{}
-
-func (handler greeterEventHandler) CanExecute(_ serverevents.IContext) bool {
-	return true
-}
-
-func (handler greeterEventHandler) Handle(context serverevents.IContext, data any) {
-	userName, ok := serverevents.ValueAs[string](data)
-	if !ok || len(userName) < 1 {
-		userName = "Anonymous"
-	}
-	context.Dispatch("greet", greeting{
-		Message: fmt.Sprintf("Hello, %s", userName),
-	}, withSameUserName(context))
-}
-
-func NewGreeterEventHandler() serverevents.IEventHandler {
-	return &greeterEventHandler{}
-}

v2/implementation_test/events/handler/greet_me_handler.go

@@ -0,0 +1,34 @@
+package handler
+
+import (
+	"fmt"
+
+	serverevents "git.apihub24.de/admin/server_events/v2"
+	"git.apihub24.de/admin/server_events/v2/implementation_test/data/dto"
+	"git.apihub24.de/admin/server_events/v2/implementation_test/events/definitions"
+	"git.apihub24.de/admin/server_events/v2/implementation_test/filter"
+)
+
+type greetMeEventHandler struct{}
+
+func NewGreetMeEventHandler() serverevents.IEventHandler {
+	return &greetMeEventHandler{}
+}
+
+func (handler *greetMeEventHandler) GetConnectedEventName() string {
+	return definitions.GreetMeEventName
+}
+
+func (handler *greetMeEventHandler) CanExecute(_ serverevents.IContext) bool {
+	return true
+}
+
+func (handler *greetMeEventHandler) Handle(context serverevents.IContext, data any) {
+	userName, ok := serverevents.ValueAs[string](data)
+	if !ok || len(userName) < 1 {
+		userName = "Anonymous"
+	}
+	context.Dispatch(definitions.NewGreetEvent(dto.Greeting{
+		Message: fmt.Sprintf("Hello, %s", userName),
+	}), filter.WithSameUserName(context))
+}

v2/implementation_test/events/handler/ping.go

@@ -0,0 +1,24 @@
+package handler
+
+import (
+	serverevents "git.apihub24.de/admin/server_events/v2"
+	"git.apihub24.de/admin/server_events/v2/implementation_test/events/definitions"
+)
+
+type pingEventHandler struct{}
+
+func NewPingEventHandler() serverevents.IEventHandler {
+	return &pingEventHandler{}
+}
+
+func (handler *pingEventHandler) GetConnectedEventName() string {
+	return definitions.PingEventName
+}
+
+func (handler *pingEventHandler) CanExecute(_ serverevents.IContext) bool {
+	return true
+}
+
+func (handler *pingEventHandler) Handle(context serverevents.IContext, _ any) {
+	context.Dispatch(definitions.NewPongEvent(), context.IsCaller)
+}

v2/implementation_test/events/ping.go

@@ -1,19 +0,0 @@
-package events
-
-import (
-	serverevents "git.apihub24.de/admin/server_events/v2"
-)
-
-type pingEventHandler struct{}
-
-func NewPingEventHandler() serverevents.IEventHandler {
-	return &pingEventHandler{}
-}
-
-func (p pingEventHandler) CanExecute(_ serverevents.IContext) bool {
-	return true
-}
-
-func (p pingEventHandler) Handle(context serverevents.IContext, _ any) {
-	context.Dispatch("pong", nil, context.IsCaller)
-}

v2/implementation_test/filter/same_username.go

@@ -0,0 +1,12 @@
+package filter
+
+import serverevents "git.apihub24.de/admin/server_events/v2"
+
+func WithSameUserName(context serverevents.IContext) func(context serverevents.IContext) bool {
+	return serverevents.CreateMetaDataFilter(context, func(c serverevents.IContext) string {
+		userName, _ := serverevents.MetadataAs[string](context, "UserName")
+		return userName
+	}, func(a string, b string) bool {
+		return a == b
+	})
+}

v2/implementation_test/main.go

@@ -1,20 +1,21 @@
 package main
 
 import (
-	di "git.apihub24.de/admin/generic-di"
-	serverevents "git.apihub24.de/admin/server_events/v2"
-	"git.apihub24.de/admin/server_events/v2/implementation_test/events"
 	"log"
 	"net/http"
 	"time"
+
+	di "git.apihub24.de/admin/generic-di"
+	serverevents "git.apihub24.de/admin/server_events/v2"
+	"git.apihub24.de/admin/server_events/v2/implementation_test/events/handler"
 )
 
 func main() {
 	serverEventsMiddleware := di.Inject[serverevents.IMiddleware]()
 	eventRegistration := di.Inject[serverevents.IEventHandlerRegistration]()
 
-	eventRegistration.Add("ping", events.NewPingEventHandler)
+	eventRegistration.Use(handler.NewPingEventHandler)
-	eventRegistration.Add("greet me", events.NewGreeterEventHandler)
+	eventRegistration.Use(handler.NewGreetMeEventHandler)
 
 	router := http.NewServeMux()
 

v2/registration.go

@@ -2,8 +2,9 @@ package serverevents
 
 import (
 	"fmt"
-	di "git.apihub24.de/admin/generic-di"
 	"sync"
+
+	di "git.apihub24.de/admin/generic-di"
 )
 
 func init() {
@@ -11,7 +12,7 @@ func init() {
 }
 
 type IEventHandlerRegistration interface {
-	Add(eventType string, creator func() IEventHandler)
+	Use(creator func() IEventHandler)
 	GetHandler(eventType string) (IEventHandler, error)
 }
 
@@ -29,16 +30,14 @@ func newEventHandlerRegistration() IEventHandlerRegistration {
 	}
 }
 
-func (registration *eventHandlerRegistration) Add(eventType string, creator func() IEventHandler) {
+func (registration *eventHandlerRegistration) Use(creator func() IEventHandler) {
 	registration.mutex.Lock()
 	defer registration.mutex.Unlock()
 
-	if _, ok := registration.instances[eventType]; ok {
+	tmp := creator()
-		delete(registration.instances, eventType)
+	eventType := tmp.GetConnectedEventName()
-	}
+	delete(registration.instances, eventType)
-	if _, ok := registration.creators[eventType]; ok {
+	delete(registration.creators, eventType)
-		delete(registration.creators, eventType)
-	}
 	registration.creators[eventType] = creator
 }