Handle empty recording days and stale playback queries

app.py

@@ -310,6 +310,15 @@ def media_json(path, playback=False):
         req = urllib.request.Request(target, headers={'Authorization': MEDIA_AUTH})
         with urllib.request.urlopen(req, timeout=5) as r:
             return json.load(r)
+    except urllib.error.HTTPError as exc:
+        if playback and path.startswith('/list?') and exc.code == 404:
+            try:
+                detail = json.loads(exc.read(4096))
+                if detail.get('error') == 'no recording segments found':
+                    return []
+            except (ValueError, AttributeError):
+                pass
+        raise Problem('视频服务暂不可用，或该时段尚无可回放录像', 503)
     except Exception:
         raise Problem('视频服务暂不可用，或该时段尚无可回放录像', 503)
 
@@ -402,9 +411,9 @@ def storage_watch():
 def discover(network):
     def probe(ip):
         try:
-            with socket.create_connection((str(ip), 554), timeout=0.7) as s:
-                s.settimeout(1)
-                s.sendall(('OPTIONS rtsp://' + str(ip) + '/ RTSP/1.0\r\nCSeq: 1\r\n\r\n').encode())
+            with socket.create_connection((str(ip), 554), timeout=1.5) as s:
+                s.settimeout(3)
+                s.sendall(('OPTIONS rtsp://' + str(ip) + ':554/ RTSP/1.0\r\nCSeq: 1\r\nUser-Agent: ZhaoVision\r\n\r\n').encode())
                 response = s.recv(1024).decode(errors='replace').split('\r\n')[0]
                 if response.startswith('RTSP/'):
                     return {'host': str(ip), 'port': 554, 'response': response, 'authenticated': False}