TDengine/docs/examples/python/tmq_assignment_example.py

56 lines
1.8 KiB
Python

import taos
from taos.tmq import Consumer
import taosws
def prepare():
conn = taos.connect()
conn.execute("drop topic if exists tmq_assignment_demo_topic")
conn.execute("drop database if exists tmq_assignment_demo_db")
conn.execute("create database if not exists tmq_assignment_demo_db wal_retention_period 3600 keep 36500")
conn.select_db("tmq_assignment_demo_db")
conn.execute(
"create table if not exists tmq_assignment_demo_table (ts timestamp, c1 int, c2 float, c3 binary(10)) tags(t1 int)")
conn.execute(
"create topic if not exists tmq_assignment_demo_topic as select ts, c1, c2, c3 from tmq_assignment_demo_table")
conn.execute("insert into d0 using tmq_assignment_demo_table tags (0) values (now-2s, 1, 1.0, 'tmq test')")
conn.execute("insert into d0 using tmq_assignment_demo_table tags (0) values (now-1s, 2, 2.0, 'tmq test')")
conn.execute("insert into d0 using tmq_assignment_demo_table tags (0) values (now, 3, 3.0, 'tmq test')")
def taos_get_assignment_and_seek_demo():
prepare()
consumer = Consumer(
{
"group.id": "0",
}
)
consumer.subscribe(["tmq_assignment_demo_topic"])
# get topic assignment
assignments = consumer.assignment()
for assignment in assignments:
print(assignment)
# poll
consumer.poll(1)
consumer.poll(1)
# get topic assignment again
after_pool_assignments = consumer.assignment()
for assignment in after_pool_assignments:
print(assignment)
# seek to the beginning
for assignment in assignments:
consumer.seek(assignment)
# now the assignment should be the same as before poll
assignments = consumer.assignment()
for assignment in assignments:
print(assignment)
if __name__ == '__main__':
taos_get_assignment_and_seek_demo()