mirror of https://github.com/zulip/zulip.git
85 lines
3.3 KiB
Python
85 lines
3.3 KiB
Python
# Documented in https://zulip.readthedocs.io/en/latest/subsystems/queuing.html
|
|
import logging
|
|
from typing import Any, Dict, List, Tuple
|
|
|
|
from django.db import connection
|
|
from psycopg2.sql import SQL, Literal
|
|
from typing_extensions import override
|
|
|
|
from zerver.worker.base import LoopQueueProcessingWorker, assign_queue
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
@assign_queue("user_activity")
|
|
class UserActivityWorker(LoopQueueProcessingWorker):
|
|
"""The UserActivity queue is perhaps our highest-traffic queue, and
|
|
requires some care to ensure it performs adequately.
|
|
|
|
We use a LoopQueueProcessingWorker as a performance optimization
|
|
for managing the queue. The structure of UserActivity records is
|
|
such that they are easily deduplicated before being sent to the
|
|
database; we take advantage of that to make this queue highly
|
|
effective at dealing with a backlog containing many similar
|
|
events. Such a backlog happen in a few ways:
|
|
|
|
* In abuse/DoS situations, if a client is sending huge numbers of
|
|
similar requests to the server.
|
|
* If the queue ends up with several minutes of backlog e.g. due to
|
|
downtime of the queue processor, many clients will have several
|
|
common events from doing an action multiple times.
|
|
|
|
"""
|
|
|
|
client_id_map: Dict[str, int] = {}
|
|
|
|
@override
|
|
def start(self) -> None:
|
|
# For our unit tests to make sense, we need to clear this on startup.
|
|
self.client_id_map = {}
|
|
super().start()
|
|
|
|
@override
|
|
def consume_batch(self, user_activity_events: List[Dict[str, Any]]) -> None:
|
|
uncommitted_events: Dict[Tuple[int, int, str], Tuple[int, float]] = {}
|
|
|
|
# First, we drain the queue of all user_activity events and
|
|
# deduplicate them for insertion into the database.
|
|
for event in user_activity_events:
|
|
user_profile_id = event["user_profile_id"]
|
|
client_id = event["client_id"]
|
|
|
|
key_tuple = (user_profile_id, client_id, event["query"])
|
|
if key_tuple not in uncommitted_events:
|
|
uncommitted_events[key_tuple] = (1, event["time"])
|
|
else:
|
|
count, event_time = uncommitted_events[key_tuple]
|
|
uncommitted_events[key_tuple] = (count + 1, max(event_time, event["time"]))
|
|
|
|
rows = []
|
|
for key_tuple, value_tuple in uncommitted_events.items():
|
|
user_profile_id, client_id, query = key_tuple
|
|
count, event_time = value_tuple
|
|
rows.append(
|
|
SQL("({},{},{},{},to_timestamp({}))").format(
|
|
Literal(user_profile_id),
|
|
Literal(client_id),
|
|
Literal(query),
|
|
Literal(count),
|
|
Literal(event_time),
|
|
)
|
|
)
|
|
|
|
# Perform a single bulk UPSERT for all of the rows
|
|
sql_query = SQL(
|
|
"""
|
|
INSERT INTO zerver_useractivity(user_profile_id, client_id, query, count, last_visit)
|
|
VALUES {rows}
|
|
ON CONFLICT (user_profile_id, client_id, query) DO UPDATE SET
|
|
count = zerver_useractivity.count + excluded.count,
|
|
last_visit = greatest(zerver_useractivity.last_visit, excluded.last_visit)
|
|
"""
|
|
).format(rows=SQL(", ").join(rows))
|
|
with connection.cursor() as cursor:
|
|
cursor.execute(sql_query)
|