ref: Only send 100 sessions in one envelope (#669)

sentry_sdk/client.py

@@ -2,6 +2,7 @@
 import uuid
 import random
 from datetime import datetime
+from itertools import islice
 import socket
 
 from sentry_sdk._compat import string_types, text_type, iteritems
@@ -99,10 +100,15 @@ def _init_impl(self):
         def _send_sessions(sessions):
             # type: (List[Any]) -> None
             transport = self.transport
-            if sessions and transport:
+            if not transport or not sessions:
+                return
+            sessions_iter = iter(sessions)
+            while True:
                 envelope = Envelope()
-                for session in sessions:
+                for session in islice(sessions_iter, 100):
                     envelope.add_session(session)
+                if not envelope.items:
+                    break
                 transport.capture_envelope(envelope)
 
         try:

sentry_sdk/sessions.py

@@ -170,6 +170,7 @@ def update(
         sid=None,  # type: Optional[Union[str, uuid.UUID]]
         did=None,  # type: Optional[str]
         timestamp=None,  # type: Optional[datetime]
+        started=None,  # type: Optional[datetime]
         duration=None,  # type: Optional[float]
         status=None,  # type: Optional[SessionStatus]
         release=None,  # type: Optional[str]
@@ -194,6 +195,8 @@ def update(
         if timestamp is None:
             timestamp = datetime.utcnow()
         self.timestamp = timestamp
+        if started is not None:
+            self.started = started
         if duration is not None:
             self.duration = duration
         if release is not None: