refactored heavily

transport_network.py

@@ -0,0 +1,30 @@
+# ---------------------------------------------------------------------------
+# Transport over Network
+# ---------------------------------------------------------------------------
+import socket
+
+from transport import GnssTransport
+
+
+class TcpTransport(GnssTransport):
+    def __init__(self, host: str, port: int, timeout: float = 5.0):
+        self._sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self._sock.settimeout(timeout)
+        self._sock.connect((host, port))
+        self._sock.settimeout(1.0)
+
+    def read(self, n: int) -> bytes:
+        try:
+            return self._sock.recv(n)
+        except socket.timeout:
+            return b""
+
+    def write(self, data: bytes) -> None:
+        self._sock.sendall(data)
+
+    def close(self) -> None:
+        try:
+            self._sock.shutdown(socket.SHUT_RDWR)
+        except OSError:
+            pass
+        self._sock.close()