CHANGELOG.md

v2.2.0 2018-01-14

• Added: Cache#clear now supports async, available on Redis 4.0+
• Added: Documentation for serializers and expanders
• Fixed: Preserve existing expiration value when incrementing or decrementing keys. There is also additional documentation about the non-atomicity of the increment and decrement methods. See readthis#59 for discussion.
• Fixed: Uniformly force key encodings to binary. Not all methods forced encoding of the key, which would cause incomatible encoding errors.
• Changed: Automatically duplicate frozen strings when expanding keys.

v2.1.0 2017-10-07

• Changed: Allow any redis client version between 3.0 and 5.0

v2.0.2 2016-12-12

• Fixed: Properly handle writing when the key and value are both UTF-8. Setting both the key and value to UTF-8 strings caused differing encodings to be sent to Redis. The key was UTF-8 but the value would be ASCII-8BIT, because it was compressed and then packed as 8bit integers. The workaround is to force the encoding of both strings to binary, something that will always be compatible.

  This makes Readthis actually usable with Non-English keys.

v2.0.1 2016-07-27

• Fixed: The 2.0.0 release had a typo that rendered it useless.

v2.0.0 2016-07-27

• Breaking: nil values are now rejected from read_multi output by default. Previously nil values were always preserved when fetching with read_multi. This differed from the ActiveSupport::Cache base behaviour and caused bugs in Rails 5.0. More details can be seen at readthis#39.

The old fetching behaviour, with nil intact, can be achieved by passing the retain_nils flag:

cache.read_multi('a', 'b', retain_nils: true)

This can also be set as a global option to retain backward compatibility:

config.cache_store = :readthis_store, { retain_nils: true }

v1.5.0 2016-07-18

• Added: Cache#delete_matched has been added in a resource efficient way that avoids using the "evil" KEYS command.

v1.4.1 2016-07-05

• Fixed: Require lua files relative to the Script file itself. This fixes loading scripts from Rails or other applications.

v1.4.0 2016-07-04

• Added: Readthis::Script, for dynamically loading and executing lua scripts.
• Added: Use custom mexpire to boost refresh performance with multiple keys. It is still slower than raw read performance, but much faster than naive multi expire (~1.5x faster).
• Changed: Generally tighten inline documentation.
• Fixed: Duplicate objects during dump operation when using the passthrough. When using fetch the original value was returned, including any encoding information that was prepended. From readthis#44 by @kagux
• Fixed: Only account for 3 bits when detecting serialized values, which fixes detection with 4 or more serializers configured. From readthis#45 by @kagux.
• Fixed: The max serializer guard would allow up to 8 serializers, which wasn't caught by an improper spec. From readthis#46 by @epilgrim.

v1.3.0 2016-06-08

• Added: Key expiration refreshing on read. When refresh: true is set as an instance or method option all read operations will refresh the expiration.
• Fixed: Convert float expires_in values to the nearest valid integer. Typically any value less than 1 was rounded down to 0, which is an invalid expiration. Now a value of 0.1 will be rounded up to 1, the lowest possible expiration.

v1.2.1 2016-04-06

• Fixed: Splat arguments passed to mget within Readthis::Cache#read_multi. From readthis#34 submitted by @kyohei-shimada.

v1.2.0 2015-12-16

• Added: Global connection fault tolerance. Any Redis connection error will raise be caught and a nil value will be returned instead. For fetch operations that means the block will yielded, if provided. readthis#26

v1.1.0 2015-12-07

• Fixed: Stop overwriting specific options with the default options. issue-28. Discovered and fixed by @tobinibot.
• Fixed: Handle the case when nil is explicitly passed as options to fetch.
• Changed: All errors now extend from a base ReadthisError.

v1.0.0 2015-10-05

• Changed: Remove internal Notifications module as part of instrumentation cleanup.

v1.0.0-rc.1 2015-09-27

• Fixed: Custom serializers would be encoded correcty, but would be ignored when the value was read back out, leaving the encoding flags prefixed to the value.
• Changed: There are no longer direct accessors for namespace and expires_in. Instead, the exposed options hash is used as the fallback for all operations. For ActiveSupport compliance options must be exposed, so this prevents configuration drift after initialization. readthis#21
• Added: More helpful errors are raised when attempting to use a serializer that hasn't been configured. readthis#22.

v1.0.0-beta 2015-09-18

• Breaking: This change is necessary for the consistency and portability of values going forward. All entities are now written with a set of option flags as the initial byte. This flag is later used to determine whether the entity was compressed and what was used to marshal it. There are a number of advantages to this approach, consistency and reliability being the most important. See readthis#17 for additional background.
• Added: Per-entity options can be passed through to any cache method that writes a value (write, fetch, etc). For example, this allows certain entities to be cached as JSON while all other entities are cached using Marshal. Thanks to @fabn.
• Fixed: A hash containing the cache key is passed as the payload for ActiveSupport::Notifications instrumentation, rather than the key directly. This moves the implementation in-line with the tests for the code, and prevents errors from being masked when an error occurs inside an instrumented block. readthis#20. Discovered by @banister and fixed by @workmad3.

v0.8.1 2015-09-04

• Changed: Readthis::Cache now has an accessor for the options that were passed during initialization. This is primarily to support the session store middleware provided by ActionDispatch. See readthis#16.
• Fixed: Caching nil values is now possible. Previously the value would be converted into a blank string, causing a Marshal error when loading the data. There is still some non-standard handling of nil within fetch or fetch_multi, where a cached nil value will always result in a cache miss. See readthis#15.
• Fixed: Entity compression was broken, it wouldn't unload data when the compressed size was below the compression limit. Data is now decompressed when it can the value looks to be compressed, falling back to the initial value when decompression fails. See readthis#13 for details.

v0.8.0 2015-08-26

• Breaking: The initializer now takes a single options argument instead of a url and options separately. This allows the underlying redis client to accept any options, rather than just the driver. For example, it's now possible to use Readthis with sentinel directly through the configuration.
• Changed: The hiredis driver is no longer the default. In order to use the vastly faster hiredis driver you need to pass it in during construction. See readthis#9 for more discussion.

v0.7.0 2015-08-11

• Changed: Entity initialization uses an options hash rather than keyword arguments. This allows flexibility with older Ruby versions (1.9) that aren't officially supported.
• Changed: There is no longer a hard dependency on hiredis, though it is the default. The redis driver can be configured by passing a driver: :ruby option through to the constructor.

v0.6.2 2015-04-28

• Fixed: Set expiration during write_multi, primarily effecting fetch_multi. This fixes the real issue underlying the change in v0.6.1.

v0.6.1 2015-04-28

• Changed: Expiration values are always cast to an integer before use in write operations. This prevents subtle ActiveSupport bugs where the value would be ignored by setex.

v0.6.0 2015-03-09

• Fixed: Safely handle calling read_multi without any keys. [Michael Rykov]
• Fixed: Pointed redis-activesupport at master. Only effected development and testing.
• Added: A write_multi method is no available to bulk set keys and values. It is used by fetch_multi internally to ensure that there are at most two Redis calls.

v0.5.2 2015-01-09

• Fixed: Remove the pipeline around fetch_multi writing. This will slow down fetch_multi in cache miss situations for now. It prevents a difficult to track down exception in multi-threaded situations.

v0.5.1 2014-12-30

• Fixed: The clear method now accepts an argument for compatibility with other caches. The argument is not actually used for anything.
• Changed: The delete method will always return a boolean value rather than an integer.
• Changed: Avoid multiple instrumentation calls and pool checkouts within fetch_multi calls.

v0.5.0 2014-12-12

• Added: All read and write operations are marshalled to and from storage. This allows hashes, arrays, etc. to be restored instead of always returning a string. Unlike ActiveSupport::Store::Entity, no new objects are allocated for each entity, reducing GC and improving performance.
• Fixed: Increment/Decrement interface was only accepting two params instead of three. Now accepts amount as the second parameter.
• Changed: Increment/Decrement no longer use incby and decby, as they don't work with marshalled values. This means they are not entirely atomic, so race conditions are possible.

v0.4.0 2014-12-11

• Added: Force the use of hiredis as the adapter. It is dramatically faster, but prevents the project from being used in jruby. If we get interest from some jruby projects we can soften the requirement.
• Added: Compression! Adheres to the ActiveSupport::Store documentation.
• Fixed: Gracefully handle nil passed as options to any cache method.

v0.3.0 2014-12-01

• Added: Use to_param for key expansion, only when available. Makes it possible to extract a key from any object when ActiveSupport is loaded.
• Added: Expand hashes as cache keys.
• Changed: Use mget for read_multi, faster and more synchronous than relying on pipelined.
• Changed: Delimit compound objects with a slash rather than a colon.

v0.2.0 2014-11-24

• Added: Instrument all caching methods. Will use ActiveSupport::Notifications if available, otherwise falls back to a polyfill.
• Added: Expand objects with a cache_key method and arrays of strings or objects into consistent naespaced keys.

v0.1.0 2014-11-22

• Initial release! Working as a drop in replacement for redis_store.