New web relay manager object

Author: hoffmabc

net/web_relay_manager.go

@@ -0,0 +1,116 @@
+package net
+
+import (
+	"crypto/sha256"
+	"encoding/binary"
+	"encoding/json"
+	"fmt"
+	"github.com/gorilla/websocket"
+	"github.com/mr-tron/base58/base58"
+	"github.com/multiformats/go-multihash"
+)
+
+type WebRelayManager struct {
+	webrelays []string
+	peerID string
+}
+
+type EncryptedMessage struct {
+	Message   string `json:"encryptedMessage"`
+	Recipient string `json:"recipient"`
+}
+
+type TypedMessage struct{
+	Type string
+	Data json.RawMessage
+}
+
+type SubscribeMessage struct {
+	UserID          string `json:"userID"`
+	SubscriptionKey string `json:"subscriptionKey"`
+}
+
+func NewWebRelayManager(webrelays []string, sender string) *WebRelayManager {
+	return &WebRelayManager{webrelays, sender}
+}
+
+func (wrm *WebRelayManager) SendRelayMessage(ciphertext string, recipient string) {
+	encryptedmessage := EncryptedMessage{
+		Message: ciphertext,
+		Recipient: recipient,
+	}
+
+	data, _ := json.Marshal(encryptedmessage)
+
+	typedmessage := TypedMessage{
+		Type: "EncryptedMessage",
+		Data: data,
+	}
+
+	outgoing, _ := json.Marshal(typedmessage)
+	fmt.Println(string(outgoing))
+
+	// Transmit the encrypted message to the webrelay
+	wrm.authToWebRelay(wrm.webrelays[0], outgoing)
+
+}
+
+func (wrm *WebRelayManager) authToWebRelay(server string, msg []byte) {
+
+	// Generate subscription key for web relay
+	peerIDMultihash, _ := multihash.FromB58String(wrm.peerID)
+	decoded, _ := multihash.Decode(peerIDMultihash)
+	digest := decoded.Digest
+	prefix := digest[:8]
+
+	prefix64 := binary.BigEndian.Uint64(prefix)
+
+	// Then shifting
+	shiftedPrefix64 := prefix64>>uint(48)
+
+	// Then converting back to a byte array
+	shiftedBytes := make([]byte, 8)
+	binary.BigEndian.PutUint64(shiftedBytes, shiftedPrefix64)
+
+	hashedShiftedPrefix := sha256.Sum256(shiftedBytes)
+
+	subscriptionKey, _ := multihash.Encode(hashedShiftedPrefix[:], multihash.SHA2_256)
+
+	// Generate subscribe message
+	subscribeMessage := SubscribeMessage{
+		UserID: wrm.peerID,
+		SubscriptionKey: base58.Encode([]byte(subscriptionKey)),
+	}
+
+	data, _ := json.Marshal(subscribeMessage)
+	typedmessage := TypedMessage{
+		Type: "SubscribeMessage",
+		Data: data,
+	}
+	fmt.Println(typedmessage)
+
+	socketmessage, _ := json.Marshal(typedmessage)
+
+	// Connect to websocket server
+	fmt.Printf("connecting to %s", server)
+
+	c, _, err := websocket.DefaultDialer.Dial(server, nil)
+	if err != nil {
+		log.Fatal("dial:", err)
+	}
+	defer c.Close()
+
+	err = c.WriteMessage(websocket.TextMessage, socketmessage)
+	if err != nil {
+		fmt.Println("write:", err)
+		return
+	}
+
+	err = c.WriteMessage(websocket.TextMessage, msg)
+	if err != nil {
+		fmt.Println("write:", err)
+		return
+	}
+
+}
+