Refactored code and added some exceptions avogadro-remote.py (#406)

* Refactored/added some exceptions avogadro-remote.py

Refactored the complete code into connection class and added the check for socket connection
Future class not needed in python3, revc_msg bug fix, The file is now completely functional
resolved warnings by codacy

Signed-off-by: Omar <[email protected]>

---------

Signed-off-by: Omar <[email protected]>
Signed-off-by: aditya <[email protected]>

scripts/avogadro-remote.py

@@ -1,17 +1,11 @@
 #!/usr/bin/python
-
-from __future__ import print_function
-
 import sys
 import json
 import socket
 import struct
 import tempfile
-
-
 class Connection:
     '''Process a JSON-RPC request'''
-
     def __init__(self, name="avogadro"):
         """
         Connect to the local named pipe
@@ -20,85 +14,55 @@ def __init__(self, name="avogadro"):
         """
         # create socket
         self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
-
         # connect
-        self.sock.connect(tempfile.gettempdir() + "/" + name)
-
-    def send_json(self, obj):
+        try:
+            self.sock.connect(tempfile.gettempdir() + "/" + name)
+            # print the connection statement
+            print("CONNECTION ESTABLISHED SUCCESSFULLY")
+        except Exception as exception:
+            print("error while connecting: " + str(exception))
+            sys.exit(1)
+    def __json(self, method, file):
         """
         Send a JSON-RPC request to the named pipe.
-
-        :param obj: The JSON-RPC request object.
-        """
-        self.send_message(json.dumps(obj))
-
-    def send_message(self, msg):
-        """
+        :param method: The JSON-RPC request method.
         Send a message to the named pipe
+        :param file: file corresponding to method.
 
-        :param msg: The message to send.
         """
-        size = len(msg)
-        header = struct.pack(">I", size)
-        packet = header + msg.encode("ascii")
-        self.sock.send(packet)
-
-    def receive_message(self, size=1024):
-        """
-        Receive a message from the named pipe.
-
-        :param size: The maximum size of the message to receive.
-        """
-        packet = self.sock.recv(size)
-
-        return packet[4:]
-
-    def recv_json(self):
-        '''Receive a JSON-RPC response'''
-        msg = self.recv_message()
-
-        try:
-            return json.loads(msg)
-        except Exception as exception:
-            print("error: " + str(exception))
-            return {}
-
+        if method == "recv_msg":
+            size = 1024
+            packet = self.sock.recv(size)
+            print("reply:" + str(packet[4: ]))
+        else:
+            msg = {
+                "jsonrpc": "2.0",
+                "id": 0,
+                "method": method,
+                "params": {"fileName": file},
+                }
+            json_msg = json.dumps(msg)
+            size = len(json_msg)
+            header = struct.pack(">I", size)
+            packet = header + json_msg.encode("ascii")
+            self.sock.send(packet)
+    def open_file(self, file):
+        """Opens file"""
+        # param: file is filename input by the user in string
+        method = "openFile"
+        self.__json(method, file)
+        self.__json("recv_msg", None)
+    def save_graphic(self, file):
+        """Save Graphic"""
+        method = "saveGraphic"
+        self.__json(method, file)
+        self.__json("recv_msg", None)
+    def kill(self):
+        """To kill the current operation"""
+        method = "kill"
+        self.__json(method, None)
+        self.__json("recv_msg", None)
     def close(self):
         '''Close the socket to the named pipe'''
         self.sock.close()
-
-
-if __name__ == "__main__":
-    conn = Connection()
-
-    method = sys.argv[1]
-
-    if method == "openFile":
-        conn.send_json(
-            {
-                "jsonrpc": "2.0",
-                "id": 0,
-                "method": "openFile",
-                "params": {"fileName": str(sys.argv[2])},
-            }
-        )
-    elif method == "saveGraphic":
-        conn.send_json(
-            {
-                "jsonrpc": "2.0",
-                "id": 0,
-                "method": "saveGraphic",
-                "params": {"fileName": str(sys.argv[2])},
-            }
-        )
-
-    elif method == "kill":
-        conn.send_json({"jsonrpc": "2.0", "id": 0, "method": "kill"})
-
-    else:
-        print("unknown method: " + method)
-        conn.close()
-        sys.exit(-1)
-
-    print("reply: " + str(conn.receive_message()))
-    conn.close()
+        print("CONNECTION CLOSED SUCCESSFULLY")