improve set_instrument

- this still needs some checks

seinflux.py

@@ -132,8 +132,10 @@ class SEHistory(InfluxDBWrapper):
                 for merge_key, (col_idx, curves) in col_info.items():
                     tags = summarize_tags(curves)
                     primary = tags.get(merge[0], '_value')
-                    table = Table(tags, merge_key[0], ('_time', primary))
-                    result[primary if single_merge else merge_key[1][:len(merge)]] = table
+                    final_key = primary if single_merge else merge_key[1][:len(merge)]
+                    table = result.get(final_key)
+                    if table is None:
+                        result[final_key] = table = Table(tags, merge_key[0], ('_time', primary))
                     by_idx[col_idx] = table
                 for row in rows:
                     by_idx[row[2]].append((row[0], row[1]))
@@ -221,6 +223,7 @@ class SEHistory(InfluxDBWrapper):
         for stream in sorted(all_entries):
             entries = all_entries[stream]
             current = None
+            last = None
             instrument = None
             for entry in sorted(entries, key=lambda e: e[0][0]):
                 (ts, flag), tags = entry
@@ -232,10 +235,13 @@ class SEHistory(InfluxDBWrapper):
                         tags['instrument'] = instrument
                     current = [ts, tags]
                 elif current:
-                    if ts < current[0] + 60:
-                        # probably not containing real data
-                        current = None
-            if current or include_finished:
+                    if ts > current[0] + 60:
+                        # else its probably not containing real data
+                        last = current
+                    current = None
+            if include_finished:
+                current = last
+            if current:
                 tags = current[1]
                 ins = tags.get('instrument')
                 if ins == '0':
@@ -269,12 +275,15 @@ class SEHistory(InfluxDBWrapper):
         start, end = abs_range(start, end)
         inperiod = self.query(start, end, _measurement='_stream_', _field='on', interval=interval,
                               stream=stream, device=None, instrument=None, **tags)
+        # prepend previous to the items in period or create if not there
         for key, rows in previous.items():
             if key in inperiod:
                 inperiod[key].insert(0, rows[0])
             else:
                 inperiod[key] = rows
 
+        # append items after the ones in period, ignoring keys not present in period
+        # in the same go, create by_stream dict, joining tables with common stream
         by_stream = {}  # dict <stream> of [<ts>, <flag>, <instrument>, <device>]
         for key, table in inperiod.items():
             nextrow = nextrows.get(key)
@@ -284,12 +293,13 @@ class SEHistory(InfluxDBWrapper):
             elist = by_stream.setdefault(stream, [])
             for row in table:
                 elist.append([row[0], row[1], stream, device, instrument])
+        # combine now by either instrument or stream, if instrument is undefined (='0')
         by_key = {}
         for stream, rows in by_stream.items():
             rows.sort()
             instrument = '0'
             for row in rows:
-                if row[-1] is None:
+                if not row[-1]:
                     row[-1] = instrument
                 else:
                     instrument = row[-1]
@@ -364,7 +374,7 @@ class SEHistory(InfluxDBWrapper):
         :param value: instrument, "0" to unassign the instrument or None when switching the stream off
         :param ts: the time or None when now
         """
-        flag = bool(value)
+        flag = value is not None
         try:
             previns, prevts = self.get_instrument(stream, ts, **tags)
             if prevts is not None and (previns is None or (ts or 1e10) < prevts):