Ember Data Filter Deprecation
Summary
Deprecate the store.filter API. This API was previously gated
behind a private ENV variable that was enabled by the addon
ember-data-filter.
Motivation
The filter API was a "memory leak by design". Patterns exist
with no-worse ergonomics that have better performance and do not incur memory leak penalties.
While the change in ergonomics for end consumers in minimal, the change to ember-data is substantial.
The code for this feature required significant amounts of confusing internal plumbing to ensure that
filters were rerun every time any form of mutation (update, addition, deletion) occurred to any record.
In addition to maintenance costs, this plumbing negatively affects the performance of all RecordArrays,
and slow any operations that count as mutations (such as pushing new records into the store).
By removing this feature, we significantly simplify and streamline the core of Ember Data.
Detailed design
We will provide 3 new deprecations with links to a guide on how to refactor.
These deprecations will target 3.5, meaning that the ember-data-filter addon will continue to
work and be supported through the release of ember-data 3.4.
Deprecation: ember-data-filter:filter
Deprecate the primary case (store.filter('posts', filterFn)).
Instead, users can combine store.peekAll with a computed property.
Deprecation: ember-data-filter:query-for-filter
This deprecation is specific to folks providing a query to be requested the
first time a filter is run. To do this better, users can separate their usage
of filter from their usage of query.
Deprecation: ember-data-filter:empty-filter
In the case that users were creating a filter with no method for filtering by,
a deprecation is printed letting them know that the easiest path forward is to
use peekAll, which would return the same record result set.
How we teach this
The filter API is rarely used, having been discouraged for many years. A simple post
alerting users to it's deprecation should be sufficient. The refactoring guide is
sufficiently simple that teaching folks a better way should not be much of a hurdle.
Drawbacks
Minor churn for folks that did use this API; however, the end result will improve the performance of apps using filters more so than anyone else.
Alternatives
There's been some talk of an API for local querying; however, said alternative RFC would only result in deprecating this API as well.
Unresolved questions
None