1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
#!/usr/bin/env python
# --------------------------------------------------------------------------------------------
# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License. See License.txt in the project root for license information.
# --------------------------------------------------------------------------------------------
"""
An example to show receiving events from Event Hub partitions with custom starting position.
"""
import os
from azure.eventhub import EventHubConsumerClient, EventHubProducerClient, EventData
from azure.identity import DefaultAzureCredential
FULLY_QUALIFIED_NAMESPACE = os.environ["EVENT_HUB_HOSTNAME"]
EVENTHUB_NAME = os.environ["EVENT_HUB_NAME"]
def on_partition_initialize(partition_context):
# Put your code here.
print("Partition: {} has been initialized.".format(partition_context.partition_id))
def on_partition_close(partition_context, reason):
# Put your code here.
print("Partition: {} has been closed, reason for closing: {}.".format(partition_context.partition_id, reason))
def on_error(partition_context, error):
# Put your code here. partition_context can be None in the on_error callback.
if partition_context:
print(
"An exception: {} occurred during receiving from Partition: {}.".format(
partition_context.partition_id, error
)
)
else:
print("An exception: {} occurred during the load balance process.".format(error))
def on_event(partition_context, event):
# Put your code here.
print("Received event: {} from partition: {}.".format(event.body_as_str(), partition_context.partition_id))
if __name__ == "__main__":
producer_client = EventHubProducerClient(
fully_qualified_namespace=FULLY_QUALIFIED_NAMESPACE,
eventhub_name=EVENTHUB_NAME,
credential=DefaultAzureCredential(),
)
with producer_client:
event_data_batch_to_partition_0 = producer_client.create_batch(partition_id="0")
event_data_batch_to_partition_0.add(EventData("First event in partition 0"))
event_data_batch_to_partition_0.add(EventData("Second event in partition 0"))
event_data_batch_to_partition_0.add(EventData("Third event in partition 0"))
event_data_batch_to_partition_0.add(EventData("Forth event in partition 0"))
producer_client.send_batch(event_data_batch_to_partition_0)
consumer_client = EventHubConsumerClient(
fully_qualified_namespace=FULLY_QUALIFIED_NAMESPACE,
consumer_group="$Default",
eventhub_name=EVENTHUB_NAME,
credential=DefaultAzureCredential(),
)
partition_0_prop = consumer_client.get_partition_properties("0")
partition_0_last_enqueued_sequence_number = partition_0_prop["last_enqueued_sequence_number"]
# client will receive messages from the position of the third from last event on partition 0.
starting_position = {
"0": partition_0_last_enqueued_sequence_number - 3,
}
try:
with consumer_client:
consumer_client.receive(
partition_id="0",
on_event=on_event,
on_partition_initialize=on_partition_initialize,
on_partition_close=on_partition_close,
on_error=on_error,
starting_position=starting_position,
)
except KeyboardInterrupt:
print("Stopped receiving.")
|
