# Identity Cache Changelog

## Unreleased

## 1.6.0

- Introduce `.with_deferred_parent_expiration`, which takes a block and avoids duplicate parent cache expiry. (#569)

## 1.5.6

- Minor performance improvements on association read

## 1.5.5

- Minor performance improvements on association read


## 1.5.4

- Make `prefetch_associations` work as expected on associations that have been partially prefetched

## 1.5.3

- No longer call `should_use_cache?` on embedded/prefetched associations when reading values

## 1.5.2

- Add missing `should_use_cache?` to `fetch_multi` methods.

## 1.5.1

- Fix parent cache invalidation for custom foreign key associations

## 1.5.0

- Require Active Record 7+
- Require Ruby 3+
- Improve compatibility with Active Record 7.1.

## 1.4.1

### Fixes

- Fix `fetch_multi_by` bug for queries having a single field with distinct values. (#536)

## 1.4.0

### Features

- Add `fetch_multi_by` support for composite-key indexes. (#534)

## 1.3.1

### Fixes

- Remove N+1 queries from embedded associations when using `fetch` while `should_use_cache` is false. (#531)

## 1.3.0

### Features

- Return meaningful value from `expire_cache` indicating whenever it succeeded or failed in the process. (#523)

### Fixes

- Expire parents cache when when calling `expire_cache`. (#523)
- Avoid creating too many shapes on Ruby 3.2+. (#526)

## 1.2.0

### Fixes

- Fix mem_cache_store adapter with pool_size (#489)
- Fix dalli deprecation warning about requiring 'dalli/cas/client' (#511)
- Make transitionary method IdentityCache.with_fetch_read_only_records thread-safe (#503)

### Features

- Add support for fill lock with lock wait to avoid thundering herd problem (#373)

## 1.1.0

### Fixes

- Fix double debug logging of cache hits and misses (#474)
- Fix a Rails 6.1 deprecation warning for Rails 7.0 compatibility (#482)
- Recursively install parent expiry hooks when expiring parent caches (#476)
- Expire caches before other `after_commit` callbacks (#471)
- Avoid unnecessary record cache expiry on save with no DB update (#464)
- Fix an Active Record deprecation warning by not using `Connection#type_cast` (#459)
- Fix broken `prefetch_associations` of a polymorphic `cache_belongs_to` (#461)
- Fix `should_use_cache?` check to avoid calling it on the wrong class (#454)
- Fix fetch `has_many` embedded association on record after adding to it (#449)

### Features

- Support multiple databases and transactional tests in `IdentityCache.should_use_cache?` (#293)
- Add support for the default `MemCacheStore` from `ActiveSupport` (#465)

### Breaking Changes

- Drop ruby 2.4 support, since it is no longer supported upstream (#468)

## 1.0.1

- Fix expiry of cache_has_one association with scope and `embed: :id` (#442)

## 1.0.0

- Remove inverse_name option. Specify inverse_of on the Active Record association instead. (#439)
- Bump the minimum Active Record version to 5.2 (#438)
- Remove the default embed option value from cache_has_one (#437)
- Lazily evaluate nested includes to fetch blobs in batches (#427)
- Only cache embedded association IDs when present (#397)
- Add support for ID embedded `has_one` cached associations (#393)
- Add support for polymorphic `belongs_to` cached associations (#387)
- Add `fetch_multi_by_*` support for cache_index with a single field (#368)
- Remove support for rails 4.2 (#355)
- Type cast values using attribute types before using in cache key (#354)
- Set inverse cached association for cache_has_one on cache hit (#345)
- Use `ActiveSupport:Notifications` to notify subscribers of hydration events (#341)
- Remove disable_primary_cache_index (#335)
- Remove deprecated `embed: false` cache_has_many option (#335)
- Fix column name in the preload association query when using custom primary keys (#338)
- Raise when trying to cache a belong_to association with a scope. Previously the scope was ignored on a cache hit (#323)
- Remove deprecated `never_set_inverse_association` option (#319)
- Lazy load associated classes (#306)

## 0.5.1

- Fix bug in prefetch_associations for cache_has_one associations that may be nil

## 0.5.0

- `never_set_inverse_association` and `fetch_read_only_records` are now `true` by default (#315)
- Store the class name instead of the class itself (#311)

## 0.4.1

- Deprecated embedded associations on models that don't use IDC (#305)
- Remove a respond_to? check that hides mistakes in includes hash (#307)
- Drop ruby 2.1 support (#301)
- Avoid querying when no ids are passed to fetch_multi (#297)
- Fix fetching already loaded belongs_to association (#294)
- Move `should_use_cache?` calls to the model-level (#291)
- Clone instead of dup record when readonlyifying fetched records (#292)
- Consistently store the array for cached has many associations (#288)

## 0.4.0

- Return an array from fetched association to prevent chaining. Up to now, a relation was returned by default. (#287)

## 0.3.2

- Deprecate returning non read-only records when cache is used. Set IdentityCache.fetch_readonly_records to true to avoid this. (#282)
- Use loaded association first when fetching a cache_has_many id embedded association (#280)
- Deprecate setting the inverse active record association on cache hits. Set IdentityCache.never_set_inverse_association to true to avoid this. (#279)
- Fetch association returns relation or array depending on the configuration. It was only returning a relation for cache_has_many fetch association methods. (#276)
- Stop sharing the same attributes hash between the fetched record and the memoized cache, which could interfere with dirty tracking (#267)

## 0.3.1

- Fix cache_index for non-id primary key

## 0.3.0

- Add support for includes option on cache_index and fetch_by_id
- Use ActiveRecord instantiate
- Add association pre-fetching support for fetch_by_id
- Remove support for 3.2
- Fix N+1 from fetching embedded ids on a cache miss
- Raise when trying to cache a through association. Previously it wouldn't be invalidated properly.
- Raise if a class method is called on a scope. Previously the scope was ignored.
- Raise if a class method is called on a subclass of one that included IdentityCache. This never worked properly.
- Fix cache_belongs_to on polymorphic assocations.
- Fetching a cache_belongs_to association no longer loads the belongs_to association

## 0.2.5

- Fixed support for namespaced model classes
- Added some deduplication for parent cache expiry
- Fixed some deprecation warnings in rails 4.2

## 0.2.4

- Refactoring, documentation and test changes

## 0.2.3

- PostgreSQL support
- Rails 4.2 compatibility
- Fix: Don't connect to database when calling `IdentityCache.should_use_cache?`
- Fix: Fix invalid parent cache invalidation if object is embedded in different parents

## 0.2.2

- Change: memcached is no longer a runtime dependency
- Use cache for read-only models.

## 0.2.1

- Add a fallback backend using local memory.

## 0.2.0

- Memcache CAS support

## 0.1.0

- Backwards incompatible change: Stop expiring cache on after_touch callback.
- Change: fetch_multi accepts an array of keys as argument
- Change: :embed option value from false to :ids for cache_has_many for clarity
- Fix: Consistently use ActiveRecord / Arel APIs to build SQL queries
- Fix: `SystemStackError` when fetching more records than the max stack size
- Fix: Bug in `fetch_multi` in a transaction where results weren't compacted.
- Fix: Avoid unused preload on fetch_multi with :includes option for cache miss
- Fix: reload will invalidate the local instance cache

## 0.0.7

- Add support for non-integer primary keys
- Fix: Not implemented error for cache_has_one with embed: false
- Fix: cache key to change when adding a cache_has_many association with :embed => false
- Fix: Compatibility rails 4.1 for `quote_value`, which needs default column.

## 0.0.6

- Fix: bug where previously nil-cached attribute caches weren't expired on record creation
- Fix: cache key to not change when adding a non-embedded association.
- Perf: Rails 4 Only create `CollectionProxy` when using it

## 0.0.5

## 0.0.4

- Fix: only marshal attributes, embedded associations and normalized association IDs
- Add cache version number to cache keys
- Add test case to ensure version number is updated when the marshalled format changes

## 0.0.3

- Fix: memoization for multi hits actually work
- Fix: quotes `SELECT` projection elements on cache misses
- Add CPU performance benchmark
- Fix: table names are not hardcoded anymore
- Logger now differentiates memoized vs non memoized hits

## 0.0.2

- Fix: Existent embedded entries will no longer raise when `ActiveModel::MissingAttributeError` when accessing a newly created attribute.
- Fix: Do not marshal raw ActiveRecord associations