major improvements and rework

- add stream / instrument availability data
- events contain event kind for dispatching db methods

secop.py

@@ -16,6 +16,14 @@ class EnumConvert(dict):
         return float(self[value])
 
 
+class TagsDict(dict):
+    def __init__(self, default_value):
+        self.default_value = default_value
+
+    def __missing__(self, key):
+        return self.default_value
+
+
 class SecopStream(Stream):
     ping_time = 0
 
@@ -47,12 +55,12 @@ class SecopStream(Stream):
         self.tags['device'] = self.device
         self.modules = self.descr['modules']
         self.convert = {}
-        self.original_id = {}
+        self.tags_dict = TagsDict(self.tags)
         for mod, moddesc in self.modules.items():
             for key in ('_original_id', 'original_id'):
                 value = moddesc.get(key)
                 if value:
-                    self.original_id[mod] = value
+                    self.tags_dict[mod] = dict(self.tags, device=value)
                     break
             for param, desc in moddesc['accessibles'].items():
                 dt = desc['datainfo']
@@ -64,11 +72,10 @@ class SecopStream(Stream):
         self.send('ping')
 
     def get_tags(self, key):
-        return dict(self.tags, device=self.original_id.get(key[0], self.device))
+        return self.tags_dict[key[0]]
 
     def event_generator(self):
         try:
-            cnt = 0
             for msg in self.get_lines():
                 match = UPDATE.match(msg)
                 if match:
@@ -78,23 +85,23 @@ class SecopStream(Stream):
                     cvt = self.convert.get(key)
                     if cvt:
                         data = json.loads(data)
+                        tags = self.tags_dict[key[0]]
                         if cmd == 'error_update':
                             error = ': '.join(data[0:2])
                             print(msg, repr(error))
-                            ts = data[2].get('t', time.time())
-                            value = None
+                            timestamp = data[2].get('t', time.time())
+                            yield 'error', error, key, tags, timestamp
                         else:
-                            error = None
-                            ts = data[1].get('t', time.time())
                             value = cvt(data[0])
-                        cnt += 1
-                        yield key, value, error, ts, self.get_tags(key)
+                            timestamp = data[1].get('t', time.time())
+                            yield 'value', value, key, tags, timestamp
                 elif msg == 'active':
                     # from now on, no more waiting
                     self.notimeout()
 
         except Exception as e:
             print(self.uri, repr(e))
+            raise
 
 
 SECOP_UDP_PORT = 10767
@@ -115,6 +122,8 @@ class UdpStream(Base):
                 continue
             if kind == 'for_other_node':
                 uri = msg.pop('uri')
+                if 'device' not in msg:
+                    msg['device'] = uri.split('://', 1)[-1].split(':')[0]
                 kwargs = msg
             elif kind == 'node':
                 uri = f"{addr[0]}:{msg['port']}"
@@ -152,14 +161,17 @@ class ScanStream(UdpStream):
         self.select_dict[sock.fileno()] = self
 
 
-def send_fake_udp(uri, device='fake'):
+def send_fake_udp(uri, device=None, instrument=None):
     sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
     sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
-    msg = json.dumps({
+    msg = {
         'SECoP': 'for_other_node',
         'uri': uri,
-        'device': device,
-    }, ensure_ascii=False, separators=(',', ':')).encode('utf-8')
-    sock.sendto(msg, ('255.255.255.255', SECOP_UDP_PORT))
+    }
+    if device:
+        msg['device'] = device
+    msg['instrument'] = instrument or '0'
+    sock.sendto(json.dumps(msg, ensure_ascii=False, separators=(',', ':')).encode('utf-8'),
+                ('255.255.255.255', SECOP_UDP_PORT))