Initial Commit

matrix/appservice_server.go

@@ -0,0 +1,171 @@
+package matrix
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+	"strings"
+
+	"local/sneedchatbridge/config"
+)
+
+// StartAppserviceServer starts the Appservice HTTP server on the configured
+// listen address. Synapse will POST room events here as transactions, and
+// GET user queries (ghost user checks).
+func (b *Bridge) StartAppserviceServer(cfg *config.Config) error {
+	mux := http.NewServeMux()
+
+	// -----------------------------------------------------------
+	// /transactions/<txn_id>  - Synapse pushes events here
+	// -----------------------------------------------------------
+	mux.HandleFunc("/_matrix/appservice/v1/transactions/", func(w http.ResponseWriter, r *http.Request) {
+		if !b.checkAppserviceAuth(r, cfg.MatrixAppserviceToken) {
+			http.Error(w, "unauthorized", http.StatusUnauthorized)
+			return
+		}
+		if r.Method != http.MethodPut && r.Method != http.MethodPost {
+			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+		b.handleTransaction(w, r)
+	})
+
+	// -----------------------------------------------------------
+	// /users/@user:domain  - Synapse asks if ghost user is allowed
+	// -----------------------------------------------------------
+	mux.HandleFunc("/_matrix/appservice/v1/users/", func(w http.ResponseWriter, r *http.Request) {
+		if !b.checkAppserviceAuth(r, cfg.MatrixAppserviceToken) {
+			http.Error(w, "unauthorized", http.StatusUnauthorized)
+			return
+		}
+		if r.Method != http.MethodGet {
+			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+		b.handleUserQuery(w, r, cfg)
+	})
+
+	addr := cfg.AppserviceListenAddr
+	log.Printf("🟢 Matrix Appservice HTTP server listening on %s", addr)
+	return http.ListenAndServe(addr, mux)
+}
+
+//
+// AUTHENTICATION
+//
+
+// checkAppserviceAuth enforces authorization using the appservice token
+// provided in registration.yaml as hs_token and in .env as MATRIX_APPSERVICE_TOKEN.
+func (b *Bridge) checkAppserviceAuth(r *http.Request, token string) bool {
+	// Try ?access_token=...
+	if q := r.URL.Query().Get("access_token"); q != "" {
+		return q == token
+	}
+	// Try Authorization: Bearer <token>
+	if h := r.Header.Get("Authorization"); h != "" {
+		if strings.HasPrefix(h, "Bearer ") {
+			return strings.TrimPrefix(h, "Bearer ") == token
+		}
+	}
+	return false
+}
+
+//
+// TRANSACTIONS
+//
+
+// handleTransaction receives a list of events from Synapse.
+// Synapse POSTs a JSON body like:
+//   { "events": [ { ... }, { ... } ] }
+func (b *Bridge) handleTransaction(w http.ResponseWriter, r *http.Request) {
+	var payload struct {
+		Events []map[string]interface{} `json:"events"`
+	}
+
+	if err := json.NewDecoder(r.Body).Decode(&payload); err != nil {
+		log.Printf("❌ Appservice transaction decode error: %v", err)
+		http.Error(w, "invalid json", http.StatusBadRequest)
+		return
+	}
+
+	for _, ev := range payload.Events {
+		b.routeEvent(ev)
+	}
+
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte("{}"))
+}
+
+// routeEvent takes a raw Matrix event (map[string]interface{})
+// and converts it into a strongly-typed RoomEvent struct,
+// then forwards it to the bridge core.
+func (b *Bridge) routeEvent(ev map[string]interface{}) {
+	evType, _ := ev["type"].(string)
+	roomID, _ := ev["room_id"].(string)
+	sender, _ := ev["sender"].(string)
+	eventID, _ := ev["event_id"].(string)
+
+	// Extract content if present
+	content := map[string]interface{}{}
+	if c, ok := ev["content"].(map[string]interface{}); ok {
+		content = c
+	}
+
+	// Extract unsigned if present
+	unsigned := map[string]interface{}{}
+	if u, ok := ev["unsigned"].(map[string]interface{}); ok {
+		unsigned = u
+	}
+
+	// Redaction ID if present
+	redacts, _ := ev["redacts"].(string)
+
+	// Assemble our internal event struct
+	re := RoomEvent{
+		RoomID:   roomID,
+		EventID:  eventID,
+		Sender:   sender,
+		Type:     evType,
+		Content:  content,
+		Unsigned: unsigned,
+		Redacts:  redacts,
+	}
+
+	b.HandleMatrixEvent(re)
+}
+
+//
+// USER QUERY ENDPOINT
+//
+
+// handleUserQuery answers the Appservice ghost-user existence query.
+// Synapse queries:
+//
+//   GET /_matrix/appservice/v1/users/@username:sneedchat.kiwifarms.net
+//
+// Returning `{}` approves ghost user creation.
+// Returning 404 denies.
+func (b *Bridge) handleUserQuery(w http.ResponseWriter, r *http.Request, cfg *config.Config) {
+	path := r.URL.Path
+	parts := strings.Split(path, "/")
+	if len(parts) == 0 {
+		http.Error(w, "bad request", http.StatusBadRequest)
+		return
+	}
+	mxid := parts[len(parts)-1]
+	if mxid == "" {
+		http.Error(w, "bad request", http.StatusBadRequest)
+		return
+	}
+
+	// Allow only the configured ghost-user domain
+	if !strings.HasSuffix(mxid, ":"+cfg.MatrixGhostUserDomain) {
+		http.NotFound(w, r)
+		return
+	}
+
+	// Approve creation
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte(`{}`))
+}