baseplate.frameworks.queue_consumer.deprecated
¶
Deprecated since version 1.1: This way of creating a Baseplate queue consumer is deprecated in favor of using a QueueConsumerServer and will be removed in the next major release. Instructions for ugrading are included below.
Upgrading to a QueueConsumerServer¶
To start, you will be running your queue consumer as a “server” now, so it will use baseplate-serve rather than baseplate-script as the entrypoint.
- baseplate-script run.ini consumer:run
+ baseplate-serve run.ini --bind 0.0.0.0:8080
This also means that you will need to update your config file with similar sections to what you would have for an HTTP or Thrift service.
[DEFAULT]
rabbitmq.hostname = amqp://rabbit.local:5672
rabbitmq.exchange_name = my-exchange
rabbitmq.exchange_type = direct
+ [app:main]
+ factory = my_service:make_consumer_factory
+
+ [server:main]
+ factory = baseplate.server.queue_consumer
+ max_concurrency = 1
You will also need to change your code to create a
KombuQueueConsumerFactory
with a make_consumer_factory function rather than using queue_consumer.consume
as you did for this.
from kombu import Connection, Exchange
-
- from baseplate import queue_consumer
-
- def process_links(context, msg_body, msg):
- print('processing %s' % msg_body)
-
- def run():
- queue_consumer.consume(
- baseplate=make_baseplate(cfg, app_config),
- exchange=Exchange('reddit_exchange', 'direct'),
- connection=Connection(
- hostname='amqp://guest:guest@reddit.local:5672',
- virtual_host='/',
- ),
- queue_name='process_links_q',
- routing_keys=[
- 'link_created',
- 'link_deleted',
- 'link_updated',
- ],
- handler=process_links,
- )
+
+ from baseplate import Baseplate
+ from baseplate.frameworks.queue_consumer.kombu import (
+ KombuQueueConsumerFactory,
+ )
+
+ def process_links(context, message):
+ body = message.decode()
+ print('processing %s' % body)
+
+ def make_consumer_factory(app_config):
+ baseplate = Baseplate()
+ exchange = Exchange('reddit_exchange', 'direct')
+ connection = Connection(
+ hostname='amqp://guest:guest@reddit.local:5672',
+ virtual_host='/',
+ )
+ queue_name = 'process_links_q'
+ routing_keys = ['link_created', 'link_deleted', 'link_updated']
+ return KombuQueueConsumerFactory.new(
+ baseplate=baseplate,
+ exchange=exchange,
+ connection=connection,
+ queue_name=queue_name,
+ routing_keys=routing_keys,
+ handler_fn=process_links,
+ )
Original docs¶
To create a long-running process to consume from a queue:
from kombu import Connection, Exchange
from baseplate import queue_consumer
def process_links(context, msg_body, msg):
print('processing %s' % msg_body)
def run():
queue_consumer.consume(
baseplate=make_baseplate(cfg, app_config),
exchange=Exchange('reddit_exchange', 'direct'),
connection=Connection(
hostname='amqp://guest:guest@reddit.local:5672',
virtual_host='/',
),
queue_name='process_links_q',
routing_keys=[
'link_created',
'link_deleted',
'link_updated',
],
handler=process_links,
)
This will create a queue named 'process_links_q'
and bind the routing keys
'link_created'
, 'link_deleted'
, and 'link_updated'
. It will then
register a consumer for 'process_links_q'
to read messages and feed them to
process_links
.
Register and run a queue consumer¶
-
baseplate.frameworks.queue_consumer.deprecated.
consume
(baseplate, exchange, connection, queue_name, routing_keys, handler)[source]¶ Create a long-running process to consume messages from a queue.
A queue with name
queue_name
is created and bound to therouting_keys
so messages published to therouting_keys
are routed to the queue.Next, the process registers a consumer that receives messages from the queue and feeds them to the
handler
.The
handler
function must take 3 arguments:context
: a baseplate contextmessage_body
: the text body of the messagemessage
:kombu.message.Message
The consumer will automatically
ack
each message after the handler method exits. If there is an error in processing and the message must be retried the handler should raise an exception to crash the process. This will prevent theack
and the message will be re-queued at the head of the queue.Parameters: - baseplate (
Baseplate
) – A baseplate instance for the service. - exchange (
Exchange
) – - connection (
Connection
) – - queue_name (
str
) – The name of the queue. - routing_keys (
Sequence
[str
]) – List of routing keys. - handler (
Callable
[[RequestContext
,str
,Message
],None
]) – The handler method.
Return type: _Specialform
-
class
baseplate.frameworks.queue_consumer.deprecated.
KombuConsumer
(base_consumer)[source]¶ Consumer for use in baseplate.
The
get_message()
andget_batch()
methods will automatically record diagnostic information.-
classmethod
new
(connection, queues, queue_size=100)[source]¶ Create and initialize a consumer.
Parameters: - connection (
Connection
) – The connection - queues (
Sequence
[Queue
]) – List of queues. - queue_size (
int
) – The maximum number of messages to cache in the internal queue.Queue worker queue. Defaults to 100. For an infinite size (not recommended), use queue_size=0.
Return type: - connection (
-
classmethod
If you require more direct control¶
-
class
baseplate.frameworks.queue_consumer.deprecated.
BaseKombuConsumer
(worker, worker_thread, work_queue)[source]¶ Base object for consuming messages from a queue.
A worker process accepts messages from the queue and puts them in a local work queue. The “real” consumer can then get messages with
get_message()
orget_batch()
. It is that consumer’s responsibility toack
orreject
messages.Can be used directly, outside of standard baseplate context.
-
classmethod
new
(connection, queues, queue_size=100)[source]¶ Create and initialize a consumer.
Parameters: - connection (
Connection
) – The connection - queues (
Sequence
[Queue
]) – List of queues. - queue_size (
int
) – The maximum number of messages to cache in the internal queue.Queue worker queue. Defaults to 100. For an infinite size (not recommended), use queue_size=0.
Return type: - connection (
-
classmethod