equipment_id for merged configs and routed nodes

Add a new custom module property 'original_id' indicating
the equipment_id the modules originally belongs to.
This property is only given, when distinct from the equipment_id
of the SEC node.
It happens when multiple config files are given, for all modules
but the ones given in the first file, and for routed modules,
when  multiple nodes are routed or own modules are given.

+ fix an issue in router: additional modules were ignore in case
of a single node.

+ small cosmetic changes in config.py reducing IDE complains

Change-Id: If846c47a06158629cef807d22b91f69e4f416563
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/35396
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

frappy/protocol/router.py

@@ -77,26 +77,30 @@ class SecopClient(frappy.client.SecopClient):
 
 
 class Router(frappy.protocol.dispatcher.Dispatcher):
-    singlenode = None
-
     def __init__(self, name, logger, options, srv):
         """initialize router
 
         Use the option node = <uri> for a single node or
         nodes = ["<uri1>", "<uri2>" ...] for multiple nodes.
-        If a single node is given, the node properties are forwarded transparently,
+        If a single node is given, and no more additional modules are given,
+        the node properties are forwarded transparently,
         else the description property is a merge from all client node properties.
         """
         uri = options.pop('node', None)
         uris = options.pop('nodes', None)
-        if uri and uris:
-            raise frappy.errors.ConfigError('can not specify node _and_ nodes')
+        try:
+            if uris is not None:
+                if isinstance(uris, str) or not all(isinstance(v, str) for v in uris) or uri:
+                    raise TypeError()
+            elif isinstance(uri, str):
+                uris = [uri]
+            else:
+                raise TypeError()
+        except Exception as e:
+            raise frappy.errors.ConfigError("a router needs either 'node' as a string'"
+                                            "' or 'nodes' as a list of strings") from e
         super().__init__(name, logger, options, srv)
-        if uri:
-            self.nodes = [SecopClient(uri, logger.getChild('routed'), self)]
-            self.singlenode = self.nodes[0]
-        else:
-            self.nodes = [SecopClient(uri, logger.getChild(f'routed{i}'), self) for i, uri in enumerate(uris)]
+        self.nodes = [SecopClient(uri, logger.getChild(f'routed{i}'), self) for i, uri in enumerate(uris)]
         # register callbacks
         for node in self.nodes:
             node.register_callback(None, node.updateEvent, node.descriptiveDataChange, node.nodeStateChange)
@@ -127,8 +131,8 @@ class Router(frappy.protocol.dispatcher.Dispatcher):
                 logger.warning('can not connect to node %r', node.nodename)
 
     def handle_describe(self, conn, specifier, data):
-        if self.singlenode:
-            return DESCRIPTIONREPLY, specifier, self.singlenode.descriptive_data
+        if len(self.nodes) == 1 and not self.secnode.modules:
+            return DESCRIPTIONREPLY, specifier, self.nodes[0].descriptive_data
         reply = super().handle_describe(conn, specifier, data)
         result = reply[2]
         allmodules = result.get('modules', {})
@@ -144,6 +148,7 @@ class Router(frappy.protocol.dispatcher.Dispatcher):
                     self.log.info('module %r is already present', modname)
                 else:
                     allmodules[modname] = moddesc
+                    moddesc.setdefault('original_id', equipment_id)
         result['modules'] = allmodules
         result['description'] = '\n\n'.join(node_description)
         return DESCRIPTIONREPLY, specifier, result