rc and message. __name__ check, so usable as module

minissdpd/submit_to_minissdpd.py

@@ -2,10 +2,11 @@
 # vim: sw=4 ts=4 expandtab
 # (c) 2021 Thomas BERNARD
 # Python 3 : code sample
-import socket
+import socket, os
 
 
 def codelength(s):
+    """ returns the given bytearray prepended with the 7-bit-encoded length """
     l = len(s)
     if l == 0:
         return b'\x00'
@@ -18,21 +19,32 @@ def codelength(s):
 
 
 def SubmitServicesToMiniSSDPD(st, usn, server, url, sockpath="/var/run/minissdpd.sock"):
+    """ submits the specified service to MiniSSDPD (if running)"""
+    # First check if sockpath exists i.e. MiniSSDPD is running
+    if not os.path.exists(sockpath):
+        return -1, f"Error: {sockpath} does not exist. Is minissdpd running?"
+    # OK, submit
     sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
     try:
         sock.connect(sockpath)
         sock.send(b'\x04' + codelength(st) + codelength(usn) + codelength(server) + codelength(url))
     except socket.error as msg:
         print(msg)
-        return -1
+        return -1, msg
     finally:
         sock.close()
-    return 0
+    return 0, "OK"
 
 
-SubmitServicesToMiniSSDPD(
+if __name__ == "__main__":
+    # Example usage
+    rc, message = SubmitServicesToMiniSSDPD(
         b'urn:schemas-upnp-org:device:InternetGatewayDevice:1',
         b'uuid:73616d61-6a6b-7a74-650a-0d24d4a5d636::urn:schemas-upnp-org:device:InternetGatewayDevice:1',
         b'MyServer/0.0',
         b'http://192.168.0.1:1234/rootDesc.xml',
-)
+    )
+    if rc == 0:
+        print("OK: submitting to MiniSSDPD went well")
+    else:
+        print("Not OK. Error message is:", message)