Metadata-Version: 1.1
Name: saferedisqueue
Version: 3.0.0
Summary: A small wrapper around Redis that provides access to a FIFO queue.
Home-page: https://github.com/hellp/saferedisqueue
Author: Fabian Neumann, ferret go GmbH
Author-email: neumann@ferret-go.com
License: Copyright (c) 2013, Fabian Neumann, ferret go GmbH
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
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    * Neither the name of the ferret go GmbH nor the names of its contributors
      may be used to endorse or promote products derived from this software
      without specific prior written permission.

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Description: ==============
        saferedisqueue
        ==============
        
        A small wrapper around `Redis <http://www.redis.io>`_ (using the "standard"
        `Python redis client lib <https://pypi.python.org/pypi/redis>`_) that provides
        access to a FIFO queue and allows upstream code to mark pop'ed items as
        processed successfully (ACK'ing) or unsucessfully (FAIL'ing).
        
        Failed items are automatically requeued. Addionally a backup is kept for items
        that were neither ack'ed nor fail'ed, i.e. in case the consumer crashes. The
        backup items will be requeued as soon as one of the consumer(s) comes up
        again.
        
        All actions are atomic and it is safe to have multiple producers and consumers
        accessing the same queue concurrently.
        
        
        Version compatibility with redis.py
        ------------------------------------
        
        ===============      ===============
        redis.py             saferedisqueue
        ===============      ===============
        2.4.10 - 2.6.x       1.x
        2.7.0 - 2.7.5        no compatible version
        2.7.6 - 2.10.x       2.x-3.x
        ===============      ===============
        
        
        Usage as a library
        ==================
        
        >>> queue = SafeRedisQueue(name='test')
        >>> queue.put("Hello World")
        '595d43b2-2e49-4e96-a1d2-0848d1c7f0d3'
        >>> queue.put("Foo bar")
        '1df060eb-b578-499d-bede-20db9da8184e'
        >>> queue.get()
        ('595d43b2-2e49-4e96-a1d2-0848d1c7f0d3', 'Hello World')
        >>> queue.get()
        ('1df060eb-b578-499d-bede-20db9da8184e', 'Foo bar')
        
        Note: to be compatible with previous versions, 2 aliases ``push/pop`` exist. Start using the new ``put/get`` terminology as soon as possible since ``push/pop`` will be deleted in a future version.
        
        
        ACK'ing and FAIL'ing
        --------------------
        
        >>> queue.put("Good stuff")
        >>> queue.put("Bad stuff")
        >>> uid_good, payload_good = queue.get()
        >>> uid_bad, payload_bad = queue.get()
        ...
        # process the payloads...
        ...
        >>> queue.ack(uid_good)  # done with that one
        >>> queue.fail(uid_bad)  # something didn't work out with that one, let's requeue
        >>> uid, payload = queue.get()  # get again; we get the requeued payload again
        >>> uid == uid_bad
        True
        ...
        # try again
        ...
        >>> queue.ack(uid)  # now it worked; ACK the stuff now
        
        
        get timeout
        -----------
        
        `SafeRedisQueue.get` accepts a timeout parameter:
        
        - 0 (the default) blocks forever, waiting for items
        - a positive number blocks that amount of seconds
        - a negative timeout disables blocking
        
        
        Constructor parameters
        ----------------------
        
        `SafeRedisQueue` accepts ``*args, **kwargs`` and passes them to
        `redis.StrictRedis`, so use whatever you need.
        
        *Three exceptions*, use these in the keyword arguments to configure
        `SafeRedisQueue` itself:
        
        `url`
            Shortcut to use instead of a host/port/db/password combinations.
            Accepts "redis URLs" just as the redis library does, for example:
        
            - redis://[:password]@localhost:6379/0
            - unix://[:password]@/path/to/socket.sock?db=0
        
            When using this keyword parameter, all positional arguments (usually
            one the host) are ignored. Those two are equivalent:
        
            - ``SafeRedisQueue('localhost', port=6379, db=7)``
            - ``SafeRedisQueue(url='redis://localhost:6379/7')``
        
        `name`
            A prefix used for the keys in Redis. Default: "0", which creates the
            following keys in your Redis DB:
        
            - srq:0:items
            - srq:0:queue
            - srq:0:ackbuf
            - srq:0:backup
            - srq:0:backuplock
        
        `autoclean_interval`
            An interval in seconds (default: 60) at which *unacknowledged* items are
            requeued automatically. (They are moved from the internal ackbuf and backup data
            structures to the queue again.)
        
            Pass ``None`` to disable autocleaning. It's enabled by default!
        
        `serializer`
            An optional serializer to use on the items. Default: None
        
            Feel free to write your own serializer. It only requires a ``dumps``
            and ``loads`` methods. Modules like ``pickle``, ``json``,
            ``simplejson`` can be used out of the box.
        
            Note however, that when using Python 3 the ``json`` module has to be
            wrapped as it by default does not handle the ``bytes`` properly that
            is emitted by the underlying redis.py networking code. This should
            work::
        
                class MyJSONSerializer(object):
                    @staticmethod
                    def loads(bytes):
                        return json.loads(bytes.decode('utf-8'))
        
                    @staticmethod
                    def dumps(data):
                        return json.dumps(data)
        
                queue = SafeRedisQueue(name='foobar',serializer=MyJSONSerializer)
        
            *Added in version 3.0.0*
        
        
        Command line usage
        ==================
        
        For quick'n'dirty testing, you can use the script from the command line to put stuff into the queue::
        
            $ echo "Hello World" | python saferedisqueue.py producer
        
        ...and get it out again::
        
            $ python saferedisqueue.py consumer
            cbdabbc8-1c0f-4eb0-8733-fdb62a9c0fa6 Hello World
        
        
        =======
        Changes
        =======
        
        3.0.0 - 2014-11-13
        ------------------
        
        - BREAKING CHANGE (very unlikely, though): `push`/`put` now returns the
          uid of the just added item. Before it always returned `None`.
        - `push` has been renamed to `put`; `push` stays as an alias, but is
          deprecated and will be removed in version 4.
        - `pop` has been renamed to `get`; `pop` stays as an alias, but is
          deprecated and will be removed in version 4.
        - Increased version compatibility with redis.py to "<2.11".
        - Python 3.4 support
        - More tests. Introduced tox for testing.
        - Added `serializer` parameter to support custom serializers,
          e.g. for automatic JSON conversion. See README for details, especially
          when using Python 3.
        
        
        2.0.0 - 2014-06-26
        ------------------
        
        - SafeRedisQueue is now officially compatible with recent versions
          (roughly speaking 2.7-2.10) of redis.py.
        
          For versions 2.4 and 2.6 please continue using the 1.x development
          line.
        
          See README.rst for details on compatibility.
        
        
        1.2.0 - 2014-06-26
        ------------------
        
        - Raise compatible redis.py version up to 2.6.x. Updated README with
          compatibility details.
        
        
        
        1.1.0 - 2014-06-20
        ------------------
        
        - The constructor now accepts a "url" keyword parameter that supports
          typical redis URL a la "redis://[:password]@localhost:6379/0". See
          README for details.
        
        
        1.0.1 - 2013-06-26
        ------------------
        
        - Changed dependency on redis to require at least version 2.4.10 as
          redis.StrictRedis, which we use, was only introduced in that version.
          This should not affect anyone negatively as you wouldn't have to be able
          to use saferedisqueue at all if your project or package used an older
          version so far.
          (Thanks Telofy!)
        
        
        1.0.0 - 2013-06-05
        ------------------
        
        - Released as open-source under 3-clause BSD license. Code identical to 0.3.0.
        
        
        0.3.0 - 2012-05-22
        ------------------
        
        - The constructor now accepts an "autoclean_interval" value to set the interval
          at which the ackbuf -> backup rotation and backup requeuing happens.
          Setting the value to `None` disables autoclean completely.
          Default: 60 (seconds).
        
        
        0.2.2 - 2012-03-29
        ------------------
        
        - Negative timeout makes .pop() non-blocking.
        
        
        0.2.1 - 2012-03-09
        ------------------
        
        - Added setup.py and publish it on our internal package directory.
        
        
        0.2.0 - 2012-03-08
        ------------------
        
        - Renamed methods ("push_item" -> "push" etc.)
        - New autoclean method that is called on every .pop()
        - Internal: New names for keys in the redis db.
        
Keywords: Redis,key-value store,queue,queueing,Storm
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: BSD License
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.4
Classifier: Topic :: Internet
