https://github.com/guojiex/expire_cache
A dart FIFO auto expire cache. Should be used in flutter search.
https://github.com/guojiex/expire_cache
cache dart fifo-cache flutter mutex searchdelegate
Last synced: 7 months ago
JSON representation
A dart FIFO auto expire cache. Should be used in flutter search.
- Host: GitHub
- URL: https://github.com/guojiex/expire_cache
- Owner: guojiex
- License: mit
- Created: 2019-01-18T21:35:11.000Z (over 7 years ago)
- Default Branch: master
- Last Pushed: 2021-07-11T03:52:18.000Z (almost 5 years ago)
- Last Synced: 2025-10-23T06:56:18.537Z (7 months ago)
- Topics: cache, dart, fifo-cache, flutter, mutex, searchdelegate
- Language: Dart
- Homepage: https://pub.dev/packages/expire_cache
- Size: 41 KB
- Stars: 15
- Watchers: 1
- Forks: 2
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
# expire_cache
A dart package provides FIFO cache and its entries will expire according to time. Also proviodes
mutex like method for search usage. Check out example/async_search_example.dart.
If you want to implement
[SearchDelegate](https://github.com/flutter/flutter/search?q=SearchDelegate&unscoped_q=SearchDelegate)
in your app, you will have to cache your search results. Otherwise your call to search backend might run multiple times for the same query.
See:
https://github.com/flutter/flutter/issues/11655#issuecomment-412413030
https://github.com/flutter/flutter/issues/26759
Because this is related to search, it is valuable to expire the cache after a period of time, to give user fresh search result.
And this package provide markAsInflight function, to make sure all the later get function gets the same result(if the key is the same).
## Getting Started
This project is a starting point for a Dart
[package](https://flutter.io/developing-packages/),
a library module containing code that can be shared easily across
multiple Flutter or Dart projects.
For help getting started with Flutter, view our
[online documentation](https://flutter.io/docs), which offers tutorials,
samples, guidance on mobile development, and a full API reference.
## Development
### Run test
```bash
pub run test test/
```
or
```bash
dart pub test test/
```
## Examples
find our test file to see how to use.
### Search Example
```
class CustomSearchDataSource {
// FIFO TTL cache to cache search result.
final ExpireCache _cache =
ExpireCache();
Future cachedSearch(final SearchQuery searchQuery) async {
if (!_cache.isKeyInFlightOrInCache(searchQuery)) {
_cache.markAsInFlight(searchQuery);
} else {
return await _cache.get(searchQuery);
}
// searchQuery.runSearch is the real search call to backend
final result = await searchQuery.runSearch(this.api);
_cache.set(searchQuery, result);
print('call search backend');
return result;
}
}
```
### Normal Cache Function
```dart
final sizeLimit = 3;
final expireDuration = Duration(seconds: 120);
ExpireCache cache = ExpireCache(expireDuration: expireDuration, sizeLimit: 3);
for (int i = 0; i < sizeLimit; i++) {
cache.set(i, i);
print(cache.get(0)); // 0
```
### Mutex like usage in Search
```dart
import 'package:expire_cache/expire_cache.dart';
class _SearchObjectWithMutex {
static int cacheSetCount = 0;
static void getInflightOrSet(
ExpireCache cache, String key, String value) async {
if (!cache.isKeyInFlightOrInCache(key)) {
cache.markAsInFlight(key);
} else {
await cache.get(key);
return;
}
cacheSetCount++;
await cache.set(key, value);
}
}
class _SearchObjectWithoutMutex {
static int cacheSetCount = 0;
static void getOrSet(
ExpireCache cache, String key, String value) async {
if (await cache.get(key) != null) {
return;
}
cacheSetCount++;
await cache.set(key, value);
}
}
void main() async {
ExpireCache cache = ExpireCache();
_SearchObjectWithMutex.getInflightOrSet(cache, 'key', 'value');
await _SearchObjectWithMutex.getInflightOrSet(cache, 'key', 'value');
// Cache should only be set once.
print(
'with mutex ${_SearchObjectWithMutex.cacheSetCount}'); // 1, set is called only once.
cache.clear();
_SearchObjectWithoutMutex.getOrSet(cache, 'key', 'value2');
await _SearchObjectWithoutMutex.getOrSet(cache, 'key', 'value2');
// Cache should only be set once.
print(
'without mutex ${_SearchObjectWithoutMutex.cacheSetCount}'); // 2, because the get/set pair are run at the same time, both get will get null.
}
```