Add Manager and Provider structures with streaming capabilities

services/marketdata/internal/router/router.go

@@ -1 +1,59 @@
 package router
+
+import (
+	"gitlab.michelsen.id/phillmichelsen/tessera/services/marketdata/internal/identifier"
+	"sync"
+)
+
+type Message struct {
+	Identifier identifier.Identifier
+	Payload    any
+}
+
+type Router struct {
+	incoming <-chan Message
+	routes   map[identifier.Identifier][]chan<- Message
+	mu       sync.RWMutex
+}
+
+func NewRouter(incoming <-chan Message) *Router {
+	return &Router{
+		incoming: incoming,
+		routes:   make(map[identifier.Identifier][]chan<- Message),
+	}
+}
+
+func (r *Router) Run() {
+	for msg := range r.incoming {
+		r.mu.RLock()
+		chans := r.routes[msg.Identifier]
+		for _, ch := range chans {
+			ch <- msg
+		}
+		r.mu.RUnlock()
+	}
+}
+
+func (r *Router) Register(id identifier.Identifier, ch chan<- Message) {
+	r.mu.Lock()
+	r.routes[id] = append(r.routes[id], ch)
+	r.mu.Unlock()
+}
+
+func (r *Router) Deregister(id identifier.Identifier, ch chan<- Message) {
+	r.mu.Lock()
+	slice := r.routes[id]
+	for i := 0; i < len(slice); i++ {
+		if slice[i] == ch {
+			slice[i] = slice[len(slice)-1]
+			slice = slice[:len(slice)-1]
+			i--
+		}
+	}
+	if len(slice) == 0 {
+		delete(r.routes, id)
+	} else {
+		r.routes[id] = slice
+	}
+	r.mu.Unlock()
+}