XB8 Modems Only - Add unerrored codewords count (#5)

collect the downstream "unerrored" stat for XB8

This is available in the "CM Error Codewords" table and is useful to
know what ratio of corrected and errors you are getting to successful
codewords.

src/__main__.py

@@ -197,7 +197,7 @@ def send_to_influx(stats, config):
   current_time = datetime.now(UTC).strftime('%Y-%m-%dT%H:%M:%SZ')
 
   for stats_down in stats['downstream']:
-    series.append(Point.from_dict({
+    data = {
       'measurement': 'downstream_statistics',
       'time': current_time,
       'fields': {
@@ -211,7 +211,12 @@ def send_to_influx(stats, config):
         'channel_id': int(stats_down['channel_id']),
         'modulation': stats_down['modulation']
       }
-    }))
+    }
+    ## Only some modems, like the XB8, has the 'unerrored' value
+    if 'unerrored' in stats_down:
+      data['fields']['unerrored'] = int(stats_down['unerrored'])
+
+    series.append(Point.from_dict(data))
 
   for stats_up in stats['upstream']:
     series.append(Point.from_dict({

src/comcast_xb8_stats.py

@@ -119,6 +119,7 @@ def parse_html(html):
      # NOTE: Indexing by channel_id is important as this table might be ordered
      #       differently than the "Channel Bonding" table parsed above.
      channel = stats['downstream'][channel_id]
+     channel['unerrored'] = codeword_rows[1].find_all("td")[i].text.strip()
      channel['corrected'] = codeword_rows[2].find_all("td")[i].text.strip()
      channel['uncorrectables'] = codeword_rows[3].find_all("td")[i].text.strip()