Qpid Hawk

Bash-based Apache Qpid incremental re/configurator.

Library uses qpid-config and qpid-stat under the hood so they must present in your environment path. Import to your codebase with . "$(dirname "$(readlink -f "$0")")/qpid-hawk" snippet.

Contents

1. Targeting Broker
   1. use
2. Creating Entities 2. queue 3. binding 1. amq_topic_binding 2. amq_match_binding 2. amq_direct_binding 4. exchange 1. topic_exchange 2. direct_exchange
3. Cleanup
   1. cleanup_queues
   2. cleanup_bindings
   3. cleanup_exchanges
4. License

Targeting Broker

use

Read and cache required Qpid broker info for further usage. Subsequent invokations of other API functions are forwarded to broker selected by latest use function.

Parameter

• broker_address Host and port of broker instance to connect to.

Targeting local broker:

use '127.0.0.1'

Creating Entities

queue

Create queue if it does not exist. If queue with given name already exist command is omitted.

Parameters

• queue_name Name of the queue to create.
• Any options of qpid-config add queue can be specified:
  • --durable Queue is durable.
  • --cluster-durable Queue becomes durable if there is only one functioning cluster node.
  • --file-count N (8) Number of files in queue's persistence journal.
  • --file-size N (24) File size in pages (64Kib/page).
  • --max-queue-size N Maximum in-memory queue size as bytes.
  • --max-queue-count N Maximum in-memory queue size as a number of messages.
  • --limit-policy Action taken when queue limit is reached:
    
    • none Default value. Use broker's default policy.
    • reject Reject enqueued messages.
    • flow-to-disk Page messages to disk.
    • ring Replace oldest unacquired message with new.
    • ring-strict Replace oldest message, reject if oldest is acquired.
  • --order Set queue ordering policy:
    
    • fifo Default value. First in, first out.
    • lvq Last Value Queue ordering, allows queue browsing.
    • lvq-no-browse Last Value Queue ordering, browsing clients may lose data.
  • --generate-queue-events N If set to 1, every enqueue will generate an event that can be processed by registered listeners (e.g. for replication). If set to 2, events will be generated for enqueues and dequeues.

Creating two queues parameters reuse:

default='--durable --cluster-durable'
queue 'test.queue.1' $default
queue 'test.queue.2' $default

binding

Create new binding if it does not exist.

Implemetation Quirk. Renaming amq.match binding key that does not change of any of its parameters requires running script two times sequentially! This issue is planned to be fixed in future releases.

Parameters

• exchange_name Name of exchange to create.
• queue_name Name of queue to bind.
• binding_key Binding key name, empty by default.

Creating amq.direct binding to test.queue.2 queue:

binding 'amq.direct' 'test.queue.2' 'my_binding'

Shortcuts
binding function can be replaced with several shortcuts to omit explicit exchange name specification: amq_topic_binding, amq_match_binding and amq_direct_binding which create bindings for amq.topic, amq.match and amq.direct respectively.

amq_direct_binding 'test.message.2' 'test.queue.2'

exchange

Create new exchange if it does not exist.

Parameters

• type Type of exchange to use: topic, direct or other custom type.
• exchange_name Name of exchange to create.
• Any options of qpid-config add exchange can be specified:
  • --durable Exchange is durable.
  • --sequence Exchange will insert a qpid.msg_sequence field in the message header with a value that increments for each message forwarded.
  • --ive Exchange will behave as an initial-value-exchange, keeping a reference to the last message forwarded and enqueuing that message to newly bound queues.

Shortcuts
exchange function can be replaced with several shortcuts to omit explicit exchange type specification: topic_exchange and direct_exchange which create topic and direct exchanges respectively.

Cleanup

cleanup_queues

Remove queues from Qpid which were not touched during current configuration session.

Parameter

• skip_pattern Queues matching provided Perl pattern are preserved during cleanup, empty by default.

Excluding system queues from cleanup process:

cleanup_queues 'topic-|qmfc-|bridge_queue|qmfagent|reply|Temp|Qpid'

cleanup_bindings

Remove bindings from Qpid which were not touched during current configuration session.

Parameter

• skip_pattern Bindings matching provided pattern are preserved during cleanup, empty by default. Each binding is a sting exchnage_name queue_name binding_key wich is matched against provided pattern.

Excluding system bindings from cleanup process:

cleanup_bindings 'qpid.management|qmf.default|qmfagent|reply|bridge|Temp|Qpid'

cleanup_exchanges

Remove exchnages from Qpid which were not touched during current configuration session.

Parameter

• skip_pattern Exchnages matching provided pattern are preserved during cleanup, empty by default.

Excluding system exchanges from cleanup process:

cleanup_exchanges '^amq\.|^qpid\.|^qmf\.'

License

The code is available under MIT licence.