# (c) 2018, John Imison # GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt) from __future__ import (absolute_import, division, print_function) __metaclass__ = type DOCUMENTATION = ''' lookup: rabbitmq author: John Imison <@Im0> short_description: Retrieve messages from an AMQP/AMQPS RabbitMQ queue. description: - This lookup uses a basic get to retrieve all, or a limited number C(count), messages from a RabbitMQ queue. options: url: description: - An URI connection string to connect to the AMQP/AMQPS RabbitMQ server. - For more information refer to the URI spec U(https://www.rabbitmq.com/uri-spec.html). required: True queue: description: - The queue to get messages from. required: True count: description: - How many messages to collect from the queue. - If not set, defaults to retrieving all the messages from the queue. requirements: - The python pika package U(https://pypi.org/project/pika/). notes: - This lookup implements BlockingChannel.basic_get to get messages from a RabbitMQ server. - After retrieving a message from the server, receipt of the message is acknowledged and the message on the server is deleted. - Pika is a pure-Python implementation of the AMQP 0-9-1 protocol that tries to stay fairly independent of the underlying network support library. - More information about pika can be found at U(https://pika.readthedocs.io/en/stable/). - This plugin is tested against RabbitMQ. Other AMQP 0.9.1 protocol based servers may work but not tested/guaranteed. - Assigning the return messages to a variable under C(vars) may result in unexpected results as the lookup is evaluated every time the variable is referenced. - Currently this plugin only handles text based messages from a queue. Unexpected results may occur when retrieving binary data. ''' EXAMPLES = """ - name: Get all messages off a queue debug: msg: "{{ lookup('rabbitmq', url='amqp://guest:guest@192.168.0.10:5672/%2F', queue='hello') }}" # If you are intending on using the returned messages as a variable in more than # one task (eg. debug, template), it is recommended to set_fact. - name: Get 2 messages off a queue and set a fact for re-use set_fact: messages: "{{ lookup('rabbitmq', url='amqp://guest:guest@192.168.0.10:5672/%2F', queue='hello', count=2) }}" - name: Dump out contents of the messages debug: var: messages """ RETURN = """ _list: description: - A list of dictionaries with keys and value from the queue. type: list contains: content_type: description: The content_type on the message in the queue. type: str delivery_mode: description: The delivery_mode on the message in the queue. type: str delivery_tag: description: The delivery_tag on the message in the queue. type: str exchange: description: The exchange the message came from. type: str message_count: description: The message_count for the message on the queue. type: str msg: description: The content of the message. type: str redelivered: description: The redelivered flag. True if the message has been delivered before. type: bool routing_key: description: The routing_key on the message in the queue. type: str headers: description: The headers for the message returned from the queue. type: dict json: description: If application/json is specified in content_type, json will be loaded into variables. type: dict """ import json from ansible.errors import AnsibleError, AnsibleParserError from ansible.plugins.lookup import LookupBase from ansible.module_utils._text import to_native, to_text from ansible.utils.display import Display try: import pika from pika import spec HAS_PIKA = True except ImportError: HAS_PIKA = False display = Display() class LookupModule(LookupBase): def run(self, terms, variables=None, url=None, queue=None, count=None): if not HAS_PIKA: raise AnsibleError('pika python package is required for rabbitmq lookup.') if not url: raise AnsibleError('URL is required for rabbitmq lookup.') if not queue: raise AnsibleError('Queue is required for rabbitmq lookup.') display.vvv(u"terms:%s : variables:%s url:%s queue:%s count:%s" % (terms, variables, url, queue, count)) try: parameters = pika.URLParameters(url) except Exception as e: raise AnsibleError("URL malformed: %s" % to_native(e)) try: connection = pika.BlockingConnection(parameters) except Exception as e: raise AnsibleError("Connection issue: %s" % to_native(e)) try: conn_channel = connection.channel() except pika.exceptions.AMQPChannelError as e: try: connection.close() except pika.exceptions.AMQPConnectionError as ie: raise AnsibleError("Channel and connection closing issues: %s / %s" % to_native(e), to_native(ie)) raise AnsibleError("Channel issue: %s" % to_native(e)) ret = [] idx = 0 while True: method_frame, properties, body = conn_channel.basic_get(queue=queue) if method_frame: display.vvv(u"%s, %s, %s " % (method_frame, properties, to_text(body))) # TODO: In the future consider checking content_type and handle text/binary data differently. msg_details = dict({ 'msg': to_text(body), 'message_count': method_frame.message_count, 'routing_key': method_frame.routing_key, 'delivery_tag': method_frame.delivery_tag, 'redelivered': method_frame.redelivered, 'exchange': method_frame.exchange, 'delivery_mode': properties.delivery_mode, 'content_type': properties.content_type, 'headers': properties.headers }) if properties.content_type == 'application/json': try: msg_details['json'] = json.loads(msg_details['msg']) except ValueError as e: raise AnsibleError("Unable to decode JSON for message %s: %s" % (method_frame.delivery_tag, to_native(e))) ret.append(msg_details) conn_channel.basic_ack(method_frame.delivery_tag) idx += 1 if method_frame.message_count == 0 or idx == count: break # If we didn't get a method_frame, exit. else: break if connection.is_closed: return [ret] else: try: connection.close() except pika.exceptions.AMQPConnectionError: pass return [ret]