refactor layout and structure

proxy/internal/roundtrip/netbird.go

@@ -0,0 +1,61 @@
+package roundtrip
+
+import (
+	"fmt"
+	"net/http"
+	"sync"
+
+	"github.com/netbirdio/netbird/client/embed"
+)
+
+const deviceNamePrefix = "ingress-"
+
+// NetBird provides an http.RoundTripper implementation
+// backed by underlying NetBird connections.
+type NetBird struct {
+	mgmtAddr string
+
+	clientsMux sync.RWMutex
+	clients    map[string]*http.Client
+}
+
+func NewNetBird(mgmtAddr string) *NetBird {
+	return &NetBird{
+		mgmtAddr: mgmtAddr,
+		clients:  make(map[string]*http.Client),
+	}
+}
+
+func (n *NetBird) AddPeer(domain, key string) error {
+	client, err := embed.New(embed.Options{
+		DeviceName:    deviceNamePrefix + domain,
+		ManagementURL: n.mgmtAddr,
+		SetupKey:      key,
+	})
+	if err != nil {
+		return fmt.Errorf("create netbird client: %w", err)
+	}
+	n.clientsMux.Lock()
+	defer n.clientsMux.Unlock()
+	n.clients[domain] = client.NewHTTPClient()
+	return nil
+}
+
+func (n *NetBird) RemovePeer(domain string) {
+	n.clientsMux.Lock()
+	defer n.clientsMux.Unlock()
+	delete(n.clients, domain)
+}
+
+func (n *NetBird) RoundTrip(req *http.Request) (*http.Response, error) {
+	n.clientsMux.RLock()
+	client, exists := n.clients[req.Host]
+	// Immediately unlock after retrieval here rather than defer to avoid
+	// the call to client.Do blocking other clients being used whilst one
+	// is in use.
+	n.clientsMux.RUnlock()
+	if !exists {
+		return nil, fmt.Errorf("no peer connection found for host: %s", req.Host)
+	}
+	return client.Do(req)
+}