improve set_instrument

- this still needs some checks

secop.py

@@ -3,6 +3,7 @@ import os
 import json
 import time
 import socket
+from collections import namedtuple
 from select import select
 from streams import Stream, Base, StreamDead
 
@@ -24,6 +25,9 @@ class TagsDict(dict):
         return self.default_value
 
 
+ParamInfo = namedtuple('ParamInfo', ['cvt', 'key', 'tags'])
+
+
 class SecopStream(Stream):
     ping_time = 0
 
@@ -57,17 +61,23 @@ class SecopStream(Stream):
         self.param_info = {}
         self.tags_dict = TagsDict(self.tags)
         for mod, moddesc in self.modules.items():
+            mod_tags = None
             for key in ('_original_id', 'original_id'):
                 value = moddesc.get(key)
                 if value:
-                    self.tags_dict[mod] = dict(self.tags, device=value)
+                    mod_tags = dict(self.tags, device=value)
                     break
             parameters = moddesc['accessibles']
             for param, desc in parameters.items():
                 dt = desc['datainfo']
                 if dt['type'] in ('double', 'int', 'enum'):
                     stripped = param[1:] if param.startswith('_') else param
-                    self.param_info[mod, param] = float, (mod, param if stripped in parameters else stripped)
+                    unit = dt.get('unit')
+                    tags = self.tags or mod_tags
+                    if unit:
+                        tags = dict(tags, unit=unit)
+                    key = mod, (param if stripped in parameters else stripped)
+                    self.param_info[mod, param] = ParamInfo(float, key, tags)
         self.send('activate')
 
     def ping(self):
@@ -83,27 +93,26 @@ class SecopStream(Stream):
                 if match:
                     cmd, ident, data = match.groups()
                     mod, _, param = ident.partition(':')
-                    cvt_key = self.param_info.get((mod, param or 'value'))
-                    if cvt_key:
-                        cvt, key = cvt_key
+                    pinfo = self.param_info.get((mod, param or 'value'))
+                    if pinfo:
                         data = json.loads(data)
-                        tags = self.tags_dict[key[0]]
+                        tags = self.tags_dict[pinfo.key[0]]
                         if cmd == 'error_update':
                             error = ': '.join(data[0:2])
-                            print(msg, repr(error))
+                            # print(msg, repr(error))
                             timestamp = data[2].get('t', time.time())
-                            yield 'error', error, key, tags, timestamp
+                            yield 'error', error, pinfo.key, pinfo.tags, timestamp
                         else:
-                            value = cvt(data[0])
+                            value = pinfo.cvt(data[0])
                             timestamp = data[1].get('t', time.time())
-                            yield 'value', value, key, tags, timestamp
+                            yield 'value', value, pinfo.key, pinfo.tags, timestamp
                 elif msg == 'active':
                     # from now on, no more waiting
                     self.notimeout()
 
         except Exception as e:
+            # probably other end closed
             print(self.uri, repr(e))
-            raise
 
 
 SECOP_UDP_PORT = 10767
@@ -118,6 +127,7 @@ class UdpStream(Base):
                 msg, addr = self.socket.recvfrom(1024)
             except socket.error:  # pragma: no cover
                 return None
+            addr = socket.getnameinfo(addr, socket.NI_NOFQDN)[0]
             msg = json.loads(msg.decode('utf-8'))
             kind = msg.pop('SECoP', None)
             if not kind:
@@ -128,7 +138,7 @@ class UdpStream(Base):
                 #     msg['device'] = uri.split('://', 1)[-1].split(':')[0]
                 kwargs = msg
             elif kind == 'node':
-                uri = f"{addr[0]}:{msg['port']}"
+                uri = f"{addr}:{msg['port']}"
                 kwargs = {'name': msg['equipment_id']}
             else:
                 continue