example: add socket scripts again

examples/protocols/sockets/scripts/run_udp_server.py

@@ -0,0 +1,80 @@
+# SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: Unlicense OR CC0-1.0
+import argparse
+import socket
+from threading import Event, Thread
+
+DEF_PORT = 3333
+
+
+class UdpServer:
+
+    def __init__(self, port, family_addr, persist=False, timeout=60):  # type: ignore
+        self.port = port
+        self.family_addr = family_addr
+        self.socket = socket.socket(family_addr, socket.SOCK_DGRAM)
+        self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        self.socket.settimeout(timeout)
+        self.shutdown = Event()
+        self.persist = persist
+        self.server_thread = None
+
+    def __enter__(self):  # type: ignore
+        try:
+            self.socket.bind(('', self.port))
+        except socket.error as e:
+            print('Bind failed:{}'.format(e))
+            raise
+
+        print('Starting server on port={} family_addr={}'.format(self.port, self.family_addr))
+        self.server_thread = Thread(target=self.run_server)
+        self.server_thread.start()
+        return self
+
+    def __exit__(self, exc_type, exc_value, traceback):  # type: ignore
+        if self.persist:
+            sock = socket.socket(self.family_addr, socket.SOCK_DGRAM)
+            sock.sendto(b'Stop', ('localhost', self.port))
+            sock.close()
+            self.shutdown.set()
+        self.server_thread.join()
+        self.socket.close()
+
+    def run_server(self) -> None:
+        while not self.shutdown.is_set():
+            try:
+                data, addr = self.socket.recvfrom(1024)
+                print(addr)
+                if not data:
+                    return
+                data = data.decode()
+                print('Reply[' + addr[0] + ':' + str(addr[1]) + '] - ' + data)
+                reply = 'OK: ' + data
+                self.socket.sendto(reply.encode(), addr)
+            except socket.timeout:
+                print(f'socket recvfrom timeout ({self.socket.timeout}s)')
+            except socket.error as e:
+                print('Running server failed:{}'.format(e))
+                raise
+            if not self.persist:
+                break
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--port', default=DEF_PORT, type=int, help='UDP server port')
+    parser.add_argument('--ipv6', action='store_true', help='Create IPv6 server.')
+    parser.add_argument('--timeout', default=10, type=int, help='socket recvfrom timeout.')
+    args = parser.parse_args()
+
+    if args.ipv6:
+        family = socket.AF_INET6
+    else:
+        family = socket.AF_INET
+
+    with UdpServer(args.port, family, persist=True, timeout=args.timeout):
+        input('Server Running. Press Enter or CTRL-C to exit...\n')
+
+
+if __name__ == '__main__':
+    main()