Package: kazoo-sasl
Kazoo-sasl=====![Travis Build](https://travis-ci.org/StephenSorriaux/kazoo-sasl.svg?branch=master)![Latest Version](https://img.shields.io/pypi/v/kazoo-sasl.svg)![Downloads](https://img.shields.io/pypi/dm/kazoo-sasl.svg)`kazoo-sasl` is a fork of `kazoo` that implements a higher level API to [ApacheZookeeper](http://zookeeper.apache.org/)  with SASL for Python clients.See [the full docs](http://kazoo.rtfd.org/) for more information.License-------`kazoo-sasl` is offered under the Apache License 2.0.Authors-------`kazoo` started under the [NimbusProject](http://www.nimbusproject.org/) and through collaboration withthe open-source community has been merged with code from[Mozilla](http://www.mozilla.org/) and the [ZopeCorporation](http://zope.com/). It has since gathered an activecommunity of over fifty contributors.<a name="2.6.0"></a>## 2.6.0 (2018-07-24)#### Features* **recipe:**  added SASL digest MD5 support ([533adbba](https://github.com/python-zk/kazoo/commit/533adbbafdfb41c1bf01fdf3c188c063847b542b))<a name="2.5.0"></a>## 2.5.0 (2018-06-01)#### Performance* **recipe:**  Give TreeCache standalone queue ([4456f180](https://github.com/python-zk/kazoo/commit/4456f180735a0f8520bfc42474de9d27fa01bb2c))#### Doc*   Correctly document supported versions ([f860de52](https://github.com/python-zk/kazoo/commit/f860de5284e8ba7d0ed4171d9e5c5bef41f6b64d))*   Add license to Wheel ([43d156de](https://github.com/python-zk/kazoo/commit/43d156de3d41173d7baf6e8edb4efa377b3732fc))*   minor tweaks to contributing.md (#464) ([5837d11b](https://github.com/python-zk/kazoo/commit/5837d11bb541be1296e1b3c1842b11ceb7e743d4))#### Features* **recipe:**  allow non ephemeral locking ([6f7a603d](https://github.com/python-zk/kazoo/commit/6f7a603de9f04ec46d9946c6f5b1cb6e2b913b63))#### Chore*   drop python 2.6 compatible gevent ([2e8dcd38](https://github.com/python-zk/kazoo/commit/2e8dcd3836d01640f07e8de911cdfb3639f97d20))*   remove debian packaging (#468) ([a28423aa](https://github.com/python-zk/kazoo/commit/a28423aac7f33111388372dec50653a3091b9045))*   stop bundling virtualenv ([af9b4cab](https://github.com/python-zk/kazoo/commit/af9b4cab39982d961647afca8119816ffe7bf5e6))*   remove python 3.3 from tox ([cf66474b](https://github.com/python-zk/kazoo/commit/cf66474b27b4efc9f65e292434c2fcffb697d34d))*   remove `easy_install` instructions ([6e6627d5](https://github.com/python-zk/kazoo/commit/6e6627d58628dec11d127fc5508f9a1d16e9c317))#### Bug Fixes*   Pass watch as keyword arg instead of positional arg (#495) ([23850792](https://github.com/python-zk/kazoo/commit/2385079267db0bea6793c4f20588644381803a98))*   need gevent >= 1.2, not > 1.1 ([18f3531b](https://github.com/python-zk/kazoo/commit/18f3531b605119a547cfc4d5a4223b4b3f185405))*   Remove use of "async" as a variable ([225d3369](https://github.com/python-zk/kazoo/commit/225d3369c7a0736125a9375951a079f70fbe9e79), closes [#455](https://github.com/python-zk/kazoo/issues/455))* **core:***  Fix gevent 1.3b1+ timeout import ([257b5896](https://github.com/python-zk/kazoo/commit/257b58961f7ddd9db04d6efa070739a1b0404487))*  Correctly fire multiple callbacks ([0905c47b](https://github.com/python-zk/kazoo/commit/0905c47bff3cfc42382daff0d5ac81189c8ba46d))*  resolve race in IAsyncResult.wait() (#487) ([4d268adf](https://github.com/python-zk/kazoo/commit/4d268adf9837836f05dde5ec81be0d7bbd759e78))* **recipe:***  conn hangs when TreeCache refreshing ([11194137](https://github.com/python-zk/kazoo/commit/111941371daec00a2ecb5d8c29b9b1d35d6aa4ff))*  Unexpected exceptions break TreeCache ([db0c2d4f](https://github.com/python-zk/kazoo/commit/db0c2d4f8ab5ecfb367b7b2accfd9c52c1c91fcd))#### Refactor*   Unify queue factory in various handlers ([cbd02f5c](https://github.com/python-zk/kazoo/commit/cbd02f5ccc6ea9e6dd6b5da01a0397ea649143a0))<a name="2.4.0"></a>## 2.4.0 (2017-06-14)**PYTHON SUPPORTED VERSIONS CHANGE**: Please note that Kazoo no longer testson Python 2.6 or 3.3. Tested versions are 2.7, 3.4, 3.5, 3.6, and PyPy. Themultiple endpoint support for KazooClient may not work correctly on 2.6.#### Bug Fixes*   add missed parens to LockingQueue function call. ([88cf4aa7](https://github.com/python-zk/kazoo/commit/88cf4aa7bcd1437a44f6d3aeec34989c467fcf9d))* **core:**  revert PR #305 SetWatches which caused RuntimeError ([a7b45390](https://github.com/python-zk/kazoo/commit/a7b45390f3720a33c9ad3896a8a185bfb2628839))#### Features*   pep8 all the things ([92880342](https://github.com/python-zk/kazoo/commit/928803420721b81962e50d425610e62b0c12e438), closes [#445](https://github.com/python-zk/kazoo/issues/445))*   drop Python 2.6/3.3 official support, add 3.5/3.6 testing ([2faba9ff](https://github.com/python-zk/kazoo/commit/2faba9ff3bdeff151ac6c922bf65b2dcf9c7bd7b), closes [#441](https://github.com/python-zk/kazoo/issues/441))* **core:***  allow multiple endpoints in KazooClient hosts arg ([72a8d96c](https://github.com/python-zk/kazoo/commit/72a8d96ca188c3c2e93bd0243283539ebd6c16f1), closes [#411](https://github.com/python-zk/kazoo/issues/411))*  use epoll when available to support fds > 1023 ([267e61b4](https://github.com/python-zk/kazoo/commit/267e61b4323bc13505e8933fa9b89d0591af3a69), closes [#171](https://github.com/python-zk/kazoo/issues/171))* **recipe:**  Add TreeCache recipe ([ec8b337e](https://github.com/python-zk/kazoo/commit/ec8b337e6f1a4ff12e669f4b96ca98fb37ee5d8a))<a name="2.3.1"></a>## 2.3.1 (2017-06-01)#### Chore*   update MANIFEST.in to reflect changes to filenames ([c9a38c5d](https://github.com/python-zk/kazoo/commit/c9a38c5d650d6d92ff30fd3c1c792fc71db9ce02))*   add travis deployment and update ZK versions ([7d5d59cb](https://github.com/python-zk/kazoo/commit/7d5d59cb049244b89625d621c9d91d9a44c4b051), closes [#436](https://github.com/python-zk/kazoo/issues/436))2.3.0 (2017-05-31)------------------Please note, there have been a few dozen merges that failed to update thechangelog here. As such, the log here should not be considered conclusive asto the changes that are arriving in 2.3.0.Changes being made now to ensure more accuracy in the changelog will appearin all future versions going forward. Read the commit history for a betterunderstanding of changes merged between 2.2.1 and 2.3.0.All future commits must abide by the new CONTRIBUTING.md document describinghow to label commits so they can be automatically used to automaticallygenerate an accurate changelog.*WARNING:* THIS IS THE LAST KAZOO RELEASE THAT SUPPORTS PYTHON 2.6. ALL FUTUREVERSIONS WILL REQUIRE PYTHON 2.7 AND ABOVE.### Features-   allow having observers and different sized clusters### Bug Handling-   \#372: fully resolve multiple records for hosts in the zookeeperconnection string### Documentation-   Fix the recipe examples, so they actually work by connecting toZooKeeper. Without start() they just hang and can't be killed.2.2.1 (2015-06-17)------------------### Bug Handling-   handle NameError with basestring on py3k.### Documentation2.2 (2015-06-15)----------------### Documentation### Features-   Issue \#234: Add support for reconfig cluster membership operation### Bug Handling-   \#315: multiple acquires of a kazoo lock using the lock recipe wouldblock when using acquire even when non-blocking is specified (onlywhen the lock was/has been already acquired).-   \#318: At exit register takes `*args` and `**kwargs` not args andkargs### Documentation2.1 (2015-05-11)----------------### Features-   Start running tests against Zookeeper 3.5.0 alpha and explicitlyconfigure the admin.serverPort in tests to avoid port conflicts. TheZookeeper alpha version is not yet officially supported.-   Integrate eventlet *handler* support into kazoo so that along with[gevent, threading] handlers there can now be a dedicated eventlethandler for projects that need to (or want to) use eventlet (such asthose working in the openstack community). The`requirements_eventlet.txt` file lists the optional eventletrequirement(s) that needs to be satisfied when this new handler isused.-   Use `six` to nicely handle the cross compatibility of kazoo withpython 2.x and 3.x (reducing/removing the need to have customcompatibility code that replicates what six already provides).-   Add `state_change_event` to`kazoo_sasl.recipe.partitioner.SetPartitioner` which is set on everystate change.-   Add a NonBlockingLease recipe. The recipe allows e.g. cron jobsscheduled on multiple machines to ensure that at most N instanceswill run a particular job, with lease timeout for graceful handoverin case of node failures.### Bug Handling-   \#291: Kazoo lock recipe was only partially re-entrant in thatmultiple calls to acquire would obtain the the lock but the firstcall to release would remove the underlying lock. This would leavethe X - 1 other acquire statements unprotected (and no longerholding there expected lock). To fix this the comment about thatlock recipe being re-entrant has been removed and multiple acquireswill now block when attempted.-   \#78: Kazoo now uses socketpairs instead of pipes making itcompatible with Windows.-   \#144, \#221: Let client.command work with IPv6 addresses.-   \#216: Fixed timeout for ConnectionHandler.\_invoke.-   \#261: Creating a sequential znode under / doesn't work.-   \#274: Add server\_version() retries (by default 4 attempts will bemade) to better handle flakey responses.-   \#271: Fixed handling of KazooState.SUSPENDED in SetPartitioner.-   \#283: Fixed a race condition in SetPartitioner when party changesduring handling of lock acquisition.-   \#303: don't crash on random input as the hosts string.### Documentation-   \#222: Document that committed on the transaction is used to ensureonly one commit and is not an indicator of whether operations in thetransaction returned desired results.2.0 (2014-06-19)----------------### Documentation-   Extend support to Python 3.4, deprecating Python 3.2.-   Issue \#198: Mention Zake as a sophisticated kazoo mock testinglibrary.-   Issue \#181: Add documentation on basic logging setup.2.0b1 (2014-04-24)------------------### API Changes-   Null or None data is no longer treated as "". Pull req \#165, patchby Raul Gutierrez S. This will affect how you should treat null datain a znode vs. an empty string.-   Passing acl=[] to create() now works properly instead of anInvalidACLError as it returned before. Patch by Raul Gutierrez S inPR \#164.-   Removed the dependency on zope.interface. The classes in theinterfaces module are left for documentation purposes only (issue\#131).### Features-   Logging levels have been reduced.-   Logging previously at the `logging.DEBUG` level is now logged atthe `kazoo_sasl.loggingsupport.BLATHER` level (5).-   Some low-level logging previously at the `logging.INFO` level isnow logged at the `logging.DEBUG` level.-   Issue \#133: Introduce a new environment variableZOOKEEPER\_PORT\_OFFSET for the testing support, to run the testingcluster on a different range.### Bug Handling-   When authenticating via add\_auth() the auth data will be saved toensure that the authentication happens on reconnect (as is the casewhen feeding auth data via KazooClient's constructor). PR \#172,patch by Raul Gutierrez S.-   Change gevent import to remove deprecation warning when newer geventis used. PR \#191, patch by Hiroaki Kawai.-   Lock recipe was failing to use the client's sleep\_func causingissues with gevent. Issue \#150.-   Calling a DataWatch or ChildrenWatch instance twice (decorator) nowthrows an exception as only a single function can be associated witha single watcher. Issue \#154.-   Another fix for atexit handling so that when disposing ofconnections the atexit handler is removed. PR \#190, patch by DevaevMaxim.-   Fix atexit handling for kazoo threading handler, PR \#183. Patch byBrian Wickman.-   Partitioner should handle a suspended connection properly andrestore an allocated state if it was allocated previously. Patch byManish Tomar.-   Issue \#167: Closing a client that was never started throws a typeerror. Patch by Joshua Harlow.-   Passing dictionaries to KazooClient.\_\_init\_\_() wasn't actuallyworking properly. Patch by Ryan Uber.-   Issue \#119: Handler timeout takes the max of the random interval orthe read timeout to ensure a negative number isn't used for the readtimeout.-   Fix ordering of exception catches in lock.acquire as it wascapturing a parent exception before the child. Patch by ReneSac.-   Fix issue with client.stop() not always setting the client state toKeeperState.CLOSED. Patch by Jyrki Pulliainen in PR \#174.-   Issue \#169: Fixed pipes leaking into child processes.### Documentation-   Add section on contributing recipes, add maintainer/statusinformation for existing recipes.-   Add note about alternate use of DataWatch.1.3.1 (2013-09-25)------------------### Bug Handling-   \#118, \#125, \#128: Fix unknown variable in KazooClientcommand\_retry argument handling.-   \#126: Fix KazooRetry.copy to correctly copy sleep function.-   \#118: Correct session/socket timeout conversion (int vs. float).### Documentation-   \#121: Add a note about kazoo_sasl.recipe.queue.LockingQueue requiring aZookeeper 3.4+ server.1.3 (2013-09-05)----------------### Features-   \#115: Limit the backends we use for SLF4J during tests.-   \#112: Add IPv6 support. Patch by Dan Kruchinin.1.2.1 (2013-08-01)------------------### Bug Handling-   Issue \#108: Circular import fail when importingkazoo_sasl.recipe.watchers directly has now been resolved. Watchers andpartitioner properly import the KazooState fromkazoo_sasl.protocol.states rather than kazoo_sasl.client.-   Issue \#109: Partials not usable properly as a datawatch call cannow be used. All funcs will be called with 3 args and fall back to 2args if there's an argument error.-   Issue \#106, \#107: client.create\_async didn't strip change rootfrom the returned path.1.2 (2013-07-24)----------------### Features-   KazooClient can now be stopped more reliably even if its in themiddle of a long retry sleep. This utilizes the new interruptfeature of KazooRetry which lets the sleep be broken down intochunks and an interrupt function called to determine if the retryshould fail early.-   Issue \#62, \#92, \#89, \#101, \#102: Allow KazooRetry to have a maxdeadline, transition properly when connection fails to LOST, andsetup separate connection retry behavior from client command retrybehavior. Patches by Mike Lundy.-   Issue \#100: Make it easier to see exception context in threadingand connection modules.-   Issue \#85: Increase information density of logs and don't preventdynamic reconfiguration of log levels at runtime.-   Data-watchers for the same node are no longer 'stacked'. That is, ifa get and an exists call occur for the same node with the same watchfunction, then it will be registered only once. This change resultsin Kazoo behaving per Zookeeper client spec regarding repeat watchuse.### Bug Handling-   Issue \#53: Throw a warning upon starting if the chroot path doesn'texist so that it's more obvious when the chroot should be createdbefore performing more operations.-   Kazoo previously would let the same function be registered as adata-watch or child-watch multiple times, and then call it multipletimes upon being triggered. This was non-compliant Zookeeper clientbehavior, the same watch can now only be registered once for thesame znode path per Zookeeper client documentation.-   Issue \#105: Avoid rare import lock problems by moving moduleimports in client.py to the module scope.-   Issue \#103: Allow prefix-less sequential znodes.-   Issue \#98: Extend testing ZK harness to work with different filelocations on some versions of Debian/Ubuntu.-   Issue \#97: Update some docstrings to reflect current state ofhandlers.-   Issue \#62, \#92, \#89, \#101, \#102: Allow KazooRetry to have a maxdeadline, transition properly when connection fails to LOST, andsetup separate connection retry behavior from client command retrybehavior. Patches by Mike Lundy.### API Changes-   The kazoo_sasl.testing.harness.KazooTestHarness class directly inheritsfrom unittest.TestCase and you need to ensure to call its\_\_init\_\_ method.-   DataWatch no longer takes any parameters besides for the optionalfunction during instantiation. The additional options are nowimplicitly True, with the user being left to ignore events as theychoose. See the DataWatch API docs for more information.-   Issue \#99: Better exception raised when the writer fails to close.A WriterNotClosedException that inherits from KazooException is nowraised when the writer fails to close in time.1.1 (2013-06-08)----------------### Features-   Issue \#93: Add timeout option to lock/semaphore acquire methods.-   Issue \#79 / \#90: Add ability to pass the WatchedEvent to DataWatchand ChildWatch functions.-   Respect large client timeout values when closing the connection.-   Add a max\_leases consistency check to the semaphore recipe.-   Issue \#76: Extend testing helpers to allow customization of theJava classpath by specifying the new ZOOKEEPER\_CLASSPATHenvironment variable.-   Issue \#65: Allow non-blocking semaphore acquisition.### Bug Handling-   Issue \#96: Provide Windows compatibility in testing harness.-   Issue \#95: Handle errors deserializing connection response.-   Issue \#94: Clean up stray bytes in connection pipe.-   Issue \#87 / \#88: Allow re-acquiring lock after cancel.-   Issue \#77: Use timeout in initial socket connection.-   Issue \#69: Only ensure path once in lock and semaphore recipes.-   Issue \#68: Closing the connection causes exceptions to be raised bywatchers which assume the connection won't be closed when runningcommands.-   Issue \#66: Require ping reply before sending another ping,otherwise the connection will be considered dead and aConnectionDropped will be raised to trigger a reconnect.-   Issue \#63: Watchers weren't reset on lost connection.-   Issue \#58: DataWatcher failed to re-register for changes afternon-existent node was created then deleted.### API Changes-   KazooClient.create\_async now supports the makepath argument.-   KazooClient.ensure\_path now has an async version,ensure\_path\_async.1.0 (2013-03-26)----------------### Features-   Added a LockingQueue recipe. The queue first locks an item andremoves it from the queue only after the consume() method is called.This enables other nodes to retake the item if an error occurs onthe first node.### Bug Handling-   Issue \#50: Avoid problems with sleep function in mixedgevent/threading setup.-   Issue \#56: Avoid issues with watch callbacks evaluating to false.1.0b1 (2013-02-24)------------------### Features-   Refactored the internal connection handler to use a single thread.It now uses a deque and pipe to signal the ZK thread that there's anew command to send, so that the ZK thread can send it, or retrievea response. Processing ZK requests and responses serially in asingle thread eliminates the need for a bunch of the locking, thepeekable queue and two threads working on the same underlyingsocket.-   Issue \#48: Added documentation for the retry helper module.-   Issue \#55: Fix os.pipe file descriptor leak and introduce aKazooClient.close method. The method is particular useful in tests,where multiple KazooClients are created and closed in the sameprocess.### Bug Handling-   Issue \#46: Avoid TypeError in GeneratorContextManager on processshutdown.-   Issue \#43: Let DataWatch return node data if allow\_missing\_nodeis used.0.9 (2013-01-07)----------------### API Changes-   When a retry operation ultimately fails, it now raises akazoo_sasl.retry.RetryFailedError exception, instead of a generalException instance. RetryFailedError also inherits from the baseKazooException.### Features-   Improvements to Debian packaging rules.### Bug Handling-   Issue \#39 / \#41: Handle connection dropped errors during sessionwrites. Ensure client connection is re-established to a new ZK nodeif available.-   Issue \#38: Set CLOEXEC flag on all sockets when available.-   Issue \#37 / \#40: Handle timeout errors during select calls onsockets.-   Issue \#36: Correctly set ConnectionHandler.writer\_stopped even ifan exception is raised inside the writer, like a retry operationfailing.0.8 (2012-10-26)----------------### API Changes-   The KazooClient.\_\_init\_\_ took as watcher argument as its secondkeyword argument. The argument had no effect anymore since version0.5 and was removed.### Bug Handling-   Issue \#35: KazooClient.\_\_init\_\_ didn't pass onretry\_max\_delay to the retry helper.-   Issue \#34: Be more careful while handling socket connection errors.0.7 (2012-10-15)----------------### Features-   DataWatch now has a allow\_missing\_node setting that allows a watchto be set on a node that doesn't exist when the DataWatch iscreated.-   Add new Queue recipe, with optional priority support.-   Add new Counter recipe.-   Added debian packaging rules.### Bug Handling-   Issue \#31 fixed: Only catch KazooExceptions in catch-all calls.-   Issue \#15 fixed again: Force sleep delay to be a float to appeasegevent.-   Issue \#29 fixed: DataWatch and ChildrenWatch properly re-registertheir watches on server disconnect.0.6 (2012-09-27)----------------### API Changes-   Node paths are assumed to be Unicode objects. Under Python 2pure-ascii strings will also be accepted. Node values are consideredbytes. The byte type is an alias for str under Python 2.-   New KeeperState.CONNECTED\_RO state for Zookeeper servers connectedin read-only mode.-   New NotReadOnlyCallError exception when issuing a write changeagainst a server thats currently read-only.### Features-   Add support for Python 3.2, 3.3 and PyPy (only for the threadinghandler).-   Handles connecting to Zookeeper 3.4+ read-only servers.-   Automatic background scanning for a Read/Write server when connectedto a server in read-only mode.-   Add new Semaphore recipe.-   Add a new retry\_max\_delay argument to the client and by defaultlimit the retry delay to at most an hour regardless of exponentialbackoff settings.-   Add new randomize\_hosts argument to KazooClient, allowing one todisable host randomization.### Bug Handling-   Fix bug with locks not handling intermediary lock contendersdisappearing.-   Fix bug with set\_data type check failing to catch unicode values.-   Fix bug with gevent 0.13.x backport of peekable queue.-   Fix PatientChildrenWatch to use handler specific sleep function.0.5 (2012-09-06)----------------Skipping a version to reflect the magnitude of the change. Kazoo is nowa pure Python client with no C bindings. This release should run withouta problem on alternate Python implementations such as PyPy and Jython.Porting to Python 3 in the future should also be much easier.### Documentation-   Docs have been restructured to handle the new classes and locationsof the methods from the pure Python refactor.### Bug HandlingThis change may introduce new bugs, however there is no longer thepossibility of a complete Python segfault due to errors in the C libraryand/or the C binding.-   Possible segfaults from the C lib are gone.-   Password mangling due to the C lib is gone.-   The party recipes didn't set their participating flag to False afterleaving.### Features-   New client.command and client.server\_version API, exposingZookeeper's four letter commands and giving access to structuredversion information.-   Added 'include\_data' option for get\_children to include the node'sStat object.-   Substantial increase in logging data with debug mode. Allcorrespondence with the Zookeeper server can now be seen to help indebugging.### API Changes-   The testing helpers have been moved from testing.\_\_init\_\_ into atesting.harness module. The official API's of KazooTestCase andKazooTestHarness can still be directly imported from testing.-   The kazoo_sasl.handlers.util module was removed.-   Backwards compatible exception class aliases are provided for now inkazoo exceptions for the prior C exception names.-   Unicode strings now work fine for node names and are properlyconverted to and from unicode objects.-   The data value argument for the create and create\_async methods ofthe client was made optional and defaults to an empty byte string.The data value must be a byte string. Unicode values are no longerallowed and will raise a TypeError.0.3 (2012-08-23)----------------### API Changes-   Handler interface now has an rlock\_object for use by recipes.### Bug Handling-   Fixed password bug with updated zc-zookeeper-static release, whichretains null bytes in the password properly.-   Fixed reconnect hammering, so that the reconnection follows retryjitter and retry backoff's.-   Fixed possible bug with using a threading.Condition in the setpartitioner. Set partitioner uses new rlock\_object handler API toget an appropriate RLock for gevent.-   Issue \#17 fixed: Wrap timeout exceptions with staticmethod so theycan be used directly as intended. Patch by Bob Van Zant.-   Fixed bug with client reconnection looping indefinitely using anexpired session id.0.2 (2012-08-12)----------------### Documentation-   Fixed doc references to start\_async using an AsyncResult object, ituses an Event object.### Bug Handling-   Issue \#16 fixed: gevent zookeeper logging failed to handle a monkeypatched logging setup. Logging is now setup such that a greenlet isused for logging messages under gevent, and the thread one is usedotherwise.-   Fixed bug similar to \#14 for ChildrenWatch on the session listener.-   Issue \#14 fixed: DataWatch had inconsistent handling of the node itwas watching not existing. DataWatch also properly spawns its\_get\_data function to avoid blocking session events.-   Issue \#15 fixed: sleep\_func for SequentialGeventHandler was notset on the class appropriately leading to additional arguments beingpassed to gevent.sleep.-   Issue \#9 fixed: Threads/greenlets didn't gracefully shut down.Handler now has a start/stop that is used by the client when callingstart and stop that shuts down the handler workers. This addresseserrors and warnings that could be emitted upon process shutdownregarding a clean exit of the workers.-   Issue \#12 fixed: gevent 0.13 doesn't use the samestart\_new\_thread as gevent 1.0 which resulted in a fullymonkey-patched environment halting due to the wrong thread. Updatedto use the older kazoo method of getting the real thread moduleobject.### API Changes-   The KazooClient handler is now officially exposed asKazooClient.handler so that the appropriate sync objects can be usedby end-users.-   Refactored ChildrenWatcher used by SetPartitioner into a publiclyexposed PatientChildrenWatch under recipe.watchers.### Deprecations-   connect/connect\_async has been renamed to start/start\_async tobetter match the stop to indicate connection handling. The priornames are aliased for the time being.### Recipes-   Added Barrier and DoubleBarrier implementation.0.2b1 (2012-07-27)------------------### Bug Handling-   ZOOKEEPER-1318: SystemError is caught and rethrown as the properinvalid state exception in older zookeeper python bindings wherethis issue is still valid.-   ZOOKEEPER-1431: Install the latest zc-zookeeper-static library oruse the packaged ubuntu one for ubuntu 12.04 or later.-   ZOOKEEPER-553: State handling isn't checked via this method, wetrack it in a simpler manner with the watcher to ensure we know theright state.### Features-   Exponential backoff with jitter for retrying commands.-   Gevent 0.13 and 1.0b support.-   Lock, Party, SetPartitioner, and Election recipe implementations.-   Data and Children watching API's.-   State transition handling with listener registering to handlesession state changes (choose to fatal the app on sessionexpiration, etc.)-   Zookeeper logging stream redirected into Python logging channelunder the name 'Zookeeper'.-   Base client library with handler support for threading and geventasync environments.