First commands with basic structure.

- Moves DBManager to common.

watchtower-plugin/arg_parser.py

@@ -0,0 +1,74 @@
+from common.tools import is_compressed_pk, is_locator
+from exceptions import InvalidParameter
+
+
+def parse_register_arguments(args, default_port):
+    # Sanity checks
+    if len(args) == 0:
+        raise InvalidParameter("missing required parameter: tower_id")
+
+    if len(args) > 3:
+        raise InvalidParameter("too many parameters: got {}, expected 3".format(len(args)))
+
+    tower_id = args[0]
+
+    if not isinstance(tower_id, str):
+        raise InvalidParameter("tower id must be a compressed public key (33-byte hex value) " + str(args))
+
+    # tower_id is of the form tower_id@[ip][:][port]
+    if "@" in tower_id:
+        if len(args) == 1:
+            tower_id, tower_endpoint = tower_id.split("@")
+
+            if not tower_endpoint:
+                raise InvalidParameter("no tower endpoint was provided")
+
+            # Only host was specified
+            if ":" not in tower_endpoint:
+                tower_endpoint = "{}:{}".format(tower_endpoint, default_port)
+
+            # Colons where specified but no port, defaulting
+            elif tower_endpoint.endswith(":"):
+                tower_endpoint = "{}{}".format(tower_endpoint, default_port)
+
+        else:
+            raise InvalidParameter("cannot specify host as both xxx@yyy and separate arguments")
+
+    # host was specified, but no port, defaulting
+    elif len(args) == 2:
+        tower_endpoint = "{}:{}".format(args[1], default_port)
+
+    # host and port specified
+    elif len(args) == 3:
+        tower_endpoint = "{}:{}".format(args[1], args[2])
+
+    else:
+        raise InvalidParameter("tower host is missing")
+
+    if not is_compressed_pk(tower_id):
+        raise InvalidParameter("tower id must be a compressed public key (33-byte hex value)")
+
+    return tower_id, tower_endpoint
+
+
+def parse_get_appointment_arguments(args):
+    # Sanity checks
+    if len(args) == 0:
+        raise InvalidParameter("missing required parameter: tower_id")
+
+    if len(args) == 1:
+        raise InvalidParameter("missing required parameter: locator")
+
+    if len(args) > 2:
+        raise InvalidParameter("too many parameters: got {}, expected 2".format(len(args)))
+
+    tower_id = args[0]
+    locator = args[1]
+
+    if not is_compressed_pk(tower_id):
+        raise InvalidParameter("tower id must be a compressed public key (33-byte hex value)")
+
+    if not is_locator(locator):
+        raise InvalidParameter("The provided locator is not valid", locator=locator)
+
+    return tower_id, locator