Skip to content

Latest commit

 

History

History
181 lines (146 loc) · 7.15 KB

Changes.md

File metadata and controls

181 lines (146 loc) · 7.15 KB
Raw

1.0.0

** NOTE: This version of redis_failover requires that you upgrade your clients and Node Managers at the same time.

  • redis_failover now supports distributed monitoring among the Node Managers! Previously, the Node Managers were only used as a means of redundancy in case a particular node manager crashed. Starting with version 1.0 of redis_failover, the Node Managers will all periodically report their health report/snapshots. The primary Node Manager will utilize a configurable "node strategy" to determine if a particular node is available or unavailable.
  • redis_failover now supports a configurable "failover strategy" that's consulted when performing a failover. Currently, a single strategy is provided that takes into account the average latency of the last health check to the redis server.
  • Improved handling of underlying ZK client connection in RedisFailover::NodeManager
  • Add support for passing in an existing ZK client instance to RedisFailover::Cient.new
  • Reduce unnecessary writes to ZK

0.9.7.2

  • Add support for Redis#client's location method. Fixes a compatibility issue with redis_failover and Sidekiq.

0.9.7.1

  • Stop repeated attempts to acquire exclusive lock in Node Manager (#36)

0.9.7

  • Stubbed Client#client to return itself, fixes a fork reconnect bug with Resque (dbalatero)

0.9.6

  • Handle the node discovery error condition where the znode points to a master that is now a slave.

0.9.5

  • Introduce a safer master node discovery process for the Node Manager (#34)
  • Improved shutdown process for Node Manager

0.9.4

  • Preserve original master by reading from existing znode state.
  • Prevent Timeout::Error from bringing down the process (#32) (@eric)

0.9.3

  • Add lock assert for Node Manager.

0.9.2

  • Improved exception handling in NodeWatcher.

0.9.1

  • Improve nested exception handling.
  • Fix manual failover support when znode does not exist first.
  • Various fixes to work better with 1.8.7.

0.9.0

  • Make Node Manager's lock path vary with its main znode. (Bira)
  • Node Manager's znode for holding current list of redis nodes is no longer ephemeral. This is unnecessary since the current master should only be changed by redis_failover.
  • Introduce :master_only option for RedisFailover::Client (disabled by default). This option configures the client to direct all read/write operations to the master.
  • Introduce :safe_mode option (enabled by default). This option configures the client to purge its redis clients when a ZK session expires or when the client hasn't recently heard from the node manager.
  • Introduce RedisFailover::Client#on_node_change callback notification for when the currently known list of master/slave redis nodes changes.
  • Added #current_master and #current_slaves to RedisFailover::Client. This is useful for programmatically doing things based on the current master/slaves.
  • redis_node_manager should start if no redis servers are available (#29)
  • Better handling of ZK session expirations in Node Manager.

0.8.9

  • Handle errors raised by redis 3.x client (tsilen)

0.8.8

  • Use a stack for handling nested blocks in RedisFailover::Client (inspired by connection_pool gem)
  • Fix an issue with #multi and Redis 3.x.

0.8.7

  • Support TTL operation (#24)

0.8.6

  • No longer buffer output (kyohsuke)
  • Update redis/zk gem versions to latest (rudionrails)

0.8.5

  • Lock-down gemspec to version 1.1.x of redis-namespace to play nicely with redis 2.2.x.
  • Fix RedisFailover::Client#manual_failover regression (oleriesenberg)

0.8.4

  • Lock-down gemspec to redis 2.2.x in light of upcoming redis 3.x release. Once sufficient testing has been done with the 3.x release, I will relax the constraint in the gemspec.
  • Add environment-scoped configuration file support (oleriesenberg)

0.8.3

  • Added a way to gracefully shutdown/reconnect a RedisFailover::Client. (#13)
  • Upgraded to latest ZK version that supports forking.
  • Handle case where the same RedisFailover::Client is referenced by a #multi block (#14)

0.8.2

  • Fix method signature for RedisFailover::Client#respond_to_missing? (#12)

0.8.1

  • Added YARD documentation.
  • Improve ZooKeeper client connection management.
  • Upgrade to latest ZK gem stable release.

0.8.0

  • Added manual failover support (can be initiated via RedisFailover::Client#manual_failover)
  • Misc. cleanup

0.7.0

  • When new master promotion occurs, make existing slaves point to new candidate before promoting new master.
  • Add support for specifying command-line options in a config.yml file for Node Manager.
  • Upgrade to 0.9 version of ZK client and cleanup ZK connection error handling.

0.6.0

  • Add support for running multiple Node Manager processes for added redundancy (#4)
  • Add support for specifying a redis database in RedisFailover::Client (#5)
  • Improved Node Manager command-line option parsing

0.5.4

  • No longer use problematic ZK#reopen.

0.5.3

  • Handle more ZK exceptions as candidates for reconnecting the client on error.
  • Add safety check to actively purge redis clients if a RedisFailover::Client hasn't heard from the Node Manager in a certain time window.

0.5.2

  • Always try to create path before setting current state in Node Manager.
  • More explicit rescuing of exceptions.

0.5.1

  • More logging around exceptions
  • Handle re-watching on client session expirations / disconnections
  • Use an ephemeral node for the list of redis servers

0.5.0

  • redis_failover is now built on top of ZooKeeper! This means redis_failover enjoys all of the reliability, redundancy, and data consistency offered by ZooKeeper. The old fragile HTTP-based approach has been removed and will no longer be supported in favor of ZooKeeper. This does mean that in order to use redis_failover, you must have ZooKeeper installed and running. Please see the README for steps on how to do this if you don't already have ZooKeeper running in your production environment.

0.4.0

  • No longer force newly available slaves to master if already slaves of that master
  • Honor a node's slave-serve-stale-data configuration option; do not mark a sync-with-master-in-progress slave as available if its slave-serve-stale-data is disabled
  • Change reachable/unreachable wording to available/unavailable
  • Added node reconciliation, i.e. if a node comes back up, make sure that the node manager and the node agree on current role
  • More efficient use of redis client connections
  • Raise proper error for unsupported operations (i.e., those that don't make sense for a failover client)
  • Properly handle any hanging node operations in the failover server

0.3.0

  • Integrated travis-ci
  • Added background monitor to client for proactively detecting changes to current set of redis nodes

0.2.0

  • Added retry support for contacting failover server from client
  • Client now verifies proper master/slave role before attempting operation
  • General edge case cleanup for NodeManager

0.1.1

  • Fix option parser require

0.1.0

  • First release