Synnefo

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from optparse import make_option

from synnefo.lib.amqp import AMQPClient

from snf_django.management.commands import SynnefoCommand

from synnefo.logic import queues

import json

import logging

log = logging.getLogger("")

class Command(SynnefoCommand):

    help = "Resend messages from dead letter queues to original exchange"""

    option_list = SynnefoCommand.option_list + (

        make_option(

            '--keep-zombies',

            action='store_true',

            dest='keep_zombies',

            default=False,

            help="Do not remove messages that died more than one times"),

    )

    def handle(self, *args, **options):

        verbose = (options["verbosity"] == "2")

        self.keep_zombies = options["keep_zombies"]

        log_level = logging.DEBUG if verbose else logging.WARNING

        log.setLevel(log_level)

        client = AMQPClient(confirms=False)

        client.connect()

        self.client = client

        for queue in queues.QUEUES:

            dead_queue = queues.convert_queue_to_dead(queue)

            while 1:

                message = client.basic_get(dead_queue)

                if not message:

                    break

                log.debug("Received message %s", message)

                self.handle_message(message)

        client.close()

        return 0

    def handle_message(self, message):

        try:

            body = message['body']

        except KeyError:

            log.warning("Received message without body: %s", message)

            return

        try:

            body = json.loads(body)

        except ValueError:

            log.error("Removed malformed message with body %s", body)

            self.client.basic_nack(message)

            return

        if "from-dead-letter" in message['headers']:

            if not self.keep_zombies:

                log.info("Removed message that died twice %s", body)

                self.client.basic_nack(message)

                return

        try:

            headers = message['headers']

            death = headers['x-death'][0]

        except KeyError:

            log.warning("Received message without death section %s."

                        "Removing..",

                        message)

            self.client.basic_nack(message)

        # Get Routing Info

        exchange = death['exchange']

        routing_key = death['routing-keys'][0]

        # Add after Death

        body = json.dumps(body)

        self.client.basic_publish(exchange, routing_key, body,

                                  headers={"from-dead-letter": True})

        self.client.basic_ack(message)