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import taos
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")
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 taosws_get_assignment_and_seek_demo():
prepare()
consumer = taosws.Consumer(conf={
"td.connect.websocket.scheme": "ws",
# should disable snapshot,
# otherwise it will cause invalid params error
"experimental.snapshot.enable": "false",
"group.id": "0",
})
consumer.subscribe(["tmq_assignment_demo_topic"])
# get topic assignment
assignments = consumer.assignment()
for assignment in assignments:
print(assignment.to_string())
# poll
consumer.poll(1)
consumer.poll(1)
# get topic assignment again
after_poll_assignments = consumer.assignment()
for assignment in after_poll_assignments:
print(assignment.to_string())
# seek to the beginning
for assignment in assignments:
for a in assignment.assignments():
consumer.seek(assignment.topic(), a.vg_id(), a.offset())
# now the assignment should be the same as before poll
assignments = consumer.assignment()
for assignment in assignments:
print(assignment.to_string())
if __name__ == '__main__':
taosws_get_assignment_and_seek_demo()
