refactor: merge CSV/JSON handler pairs into one handler per event type + serveCSVOrJSON helper

Co-authored-by: coolaj86 <122831+coolaj86@users.noreply.github.com>

cmd/smsapid/main.go

@@ -118,12 +118,12 @@ func main() {
 
 	// Protected routes under /api/smsgw, each guarded by its specific sms:* permission.
 	smsgw := mwpkg.WithMux(mux)
-	smsgw.With(requireSMSPermission("sms:received")).HandleFunc("GET /api/smsgw/received.csv", handlerReceivedCSV)
+	smsgw.With(requireSMSPermission("sms:received")).HandleFunc("GET /api/smsgw/received.csv", handlerReceived)
-	smsgw.With(requireSMSPermission("sms:received")).HandleFunc("GET /api/smsgw/received.json", handlerReceivedJSON)
+	smsgw.With(requireSMSPermission("sms:received")).HandleFunc("GET /api/smsgw/received.json", handlerReceived)
-	smsgw.With(requireSMSPermission("sms:sent")).HandleFunc("GET /api/smsgw/sent.csv", handlerSentCSV)
+	smsgw.With(requireSMSPermission("sms:sent")).HandleFunc("GET /api/smsgw/sent.csv", handlerSent)
-	smsgw.With(requireSMSPermission("sms:sent")).HandleFunc("GET /api/smsgw/sent.json", handlerSentJSON)
+	smsgw.With(requireSMSPermission("sms:sent")).HandleFunc("GET /api/smsgw/sent.json", handlerSent)
-	smsgw.With(requireSMSPermission("sms:ping")).HandleFunc("GET /api/smsgw/ping.csv", handlerPingCSV)
+	smsgw.With(requireSMSPermission("sms:ping")).HandleFunc("GET /api/smsgw/ping.csv", handlerPing)
-	smsgw.With(requireSMSPermission("sms:ping")).HandleFunc("GET /api/smsgw/ping.json", handlerPingJSON)
+	smsgw.With(requireSMSPermission("sms:ping")).HandleFunc("GET /api/smsgw/ping.json", handlerPing)
 
 	addr := "localhost:8088"
 	fmt.Printf("Listening on %s...\n\n", addr)
@@ -196,7 +196,7 @@ func parseSinceLimit(r *http.Request) (time.Time, int) {
 	return since, limit
 }
 
-func handlerReceivedCSV(w http.ResponseWriter, r *http.Request) {
+func handlerReceived(w http.ResponseWriter, r *http.Request) {
 	since, limit := parseSinceLimit(r)
 
 	webhookMux.Lock()
@@ -216,42 +216,10 @@ func handlerReceivedCSV(w http.ResponseWriter, r *http.Request) {
 	}
 	webhookMux.Unlock()
 
-	b, err := csvutil.Marshal(rows)
+	serveCSVOrJSON(w, r, rows)
-	if err != nil {
-		http.Error(w, `{"error":"failed to encode CSV"}`, http.StatusInternalServerError)
-		return
-	}
-	w.Header().Set("Content-Type", "text/csv; charset=utf-8")
-	_, _ = w.Write(b)
 }
 
-func handlerReceivedJSON(w http.ResponseWriter, r *http.Request) {
+func handlerSent(w http.ResponseWriter, r *http.Request) {
-	since, limit := parseSinceLimit(r)
-
-	webhookMux.Lock()
-	rows := make([]*androidsmsgateway.WebhookReceived, 0, min(len(webhookEvents), limit))
-	for _, event := range webhookEvents {
-		recv, ok := event.(*androidsmsgateway.WebhookReceived)
-		if !ok {
-			continue
-		}
-		if !since.IsZero() && !recv.Payload.ReceivedAt.After(since) {
-			continue
-		}
-		rows = append(rows, recv)
-		if len(rows) >= limit {
-			break
-		}
-	}
-	webhookMux.Unlock()
-
-	w.Header().Set("Content-Type", "application/json")
-	enc := json.NewEncoder(w)
-	enc.SetEscapeHTML(false)
-	_ = enc.Encode(rows)
-}
-
-func handlerSentCSV(w http.ResponseWriter, r *http.Request) {
 	since, limit := parseSinceLimit(r)
 
 	webhookMux.Lock()
@@ -271,42 +239,10 @@ func handlerSentCSV(w http.ResponseWriter, r *http.Request) {
 	}
 	webhookMux.Unlock()
 
-	b, err := csvutil.Marshal(rows)
+	serveCSVOrJSON(w, r, rows)
-	if err != nil {
-		http.Error(w, `{"error":"failed to encode CSV"}`, http.StatusInternalServerError)
-		return
-	}
-	w.Header().Set("Content-Type", "text/csv; charset=utf-8")
-	_, _ = w.Write(b)
 }
 
-func handlerSentJSON(w http.ResponseWriter, r *http.Request) {
+func handlerPing(w http.ResponseWriter, r *http.Request) {
-	since, limit := parseSinceLimit(r)
-
-	webhookMux.Lock()
-	rows := make([]*androidsmsgateway.WebhookSent, 0, min(len(webhookEvents), limit))
-	for _, event := range webhookEvents {
-		sent, ok := event.(*androidsmsgateway.WebhookSent)
-		if !ok {
-			continue
-		}
-		if !since.IsZero() && !sent.Payload.SentAt.After(since) {
-			continue
-		}
-		rows = append(rows, sent)
-		if len(rows) >= limit {
-			break
-		}
-	}
-	webhookMux.Unlock()
-
-	w.Header().Set("Content-Type", "application/json")
-	enc := json.NewEncoder(w)
-	enc.SetEscapeHTML(false)
-	_ = enc.Encode(rows)
-}
-
-func handlerPingCSV(w http.ResponseWriter, r *http.Request) {
 	since, limit := parseSinceLimit(r)
 
 	webhookMux.Lock()
@@ -326,39 +262,25 @@ func handlerPingCSV(w http.ResponseWriter, r *http.Request) {
 	}
 	webhookMux.Unlock()
 
-	b, err := csvutil.Marshal(rows)
+	serveCSVOrJSON(w, r, rows)
+}
+
+// serveCSVOrJSON writes v as CSV when the request path ends with ".csv", otherwise as JSON.
+func serveCSVOrJSON[T any](w http.ResponseWriter, r *http.Request, v []T) {
+	if strings.HasSuffix(r.URL.Path, ".csv") {
+		b, err := csvutil.Marshal(v)
 		if err != nil {
 			http.Error(w, `{"error":"failed to encode CSV"}`, http.StatusInternalServerError)
 			return
 		}
 		w.Header().Set("Content-Type", "text/csv; charset=utf-8")
 		_, _ = w.Write(b)
-}
+		return
-
-func handlerPingJSON(w http.ResponseWriter, r *http.Request) {
-	since, limit := parseSinceLimit(r)
-
-	webhookMux.Lock()
-	rows := make([]*androidsmsgateway.WebhookPing, 0, min(len(pingEvents), limit))
-	for _, ping := range pingEvents {
-		pingedAt := ping.PingedAt
-		if pingedAt.IsZero() {
-			pingedAt = time.UnixMilli(ping.XTimestamp).UTC()
 	}
-		if !since.IsZero() && !pingedAt.After(since) {
-			continue
-		}
-		rows = append(rows, ping)
-		if len(rows) >= limit {
-			break
-		}
-	}
-	webhookMux.Unlock()
-
 	w.Header().Set("Content-Type", "application/json")
 	enc := json.NewEncoder(w)
 	enc.SetEscapeHTML(false)
-	_ = enc.Encode(rows)
+	_ = enc.Encode(v)
 }
 
 func HandleOK(w http.ResponseWriter, r *http.Request) {