Implement exchange of open transactions

list-open-transactions.py

@@ -0,0 +1,44 @@
+#! /usr/bin/env python3
+
+import base64, socket, sys
+
+def get_transaction(s, i):
+    request = b"\0\0\0\0\x05" + i.to_bytes(2, "big")
+    for _ in range(10):
+        s.sendto(request, ("::1", 62039))
+        try:
+            while True:
+                msg, sender = s.recvfrom(4096)
+                if sender[0:2] == ("::1", 62039) and len(msg) == 155 and msg[0:5] == b"\0\0\0\0\x06" and msg[5:7] == i.to_bytes(2, "big"):
+                    return msg[7:155]
+        except TimeoutError:
+            pass
+    return None
+
+def format_addr(raw_addr):
+    return base64.b64encode(raw_addr).decode()
+
+def format_amount(raw_amount):
+    int_amount = int.from_bytes(raw_amount, "big")
+    coins = int_amount // 100
+    cents = int_amount % 100
+    return f"{coins},{cents:02} cc"
+
+def main():
+    s = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM)
+    s.settimeout(1)
+    for i in range(1024):
+        transaction = get_transaction(s, i)
+        if transaction is None:
+            print("- no response from local node -", file=sys.stderr)
+            exit(1)
+        if transaction == 148 * b"\0":
+            return
+        sender = format_addr(transaction[4:36])
+        receiver = format_addr(transaction[36:68])
+        amount = format_amount(transaction[68:76])
+        fee = format_amount(transaction[76:84])
+        print(f"{sender}   {receiver}   {amount:>13} {fee:>10}")
+
+if __name__ == '__main__':
+    main()