@httpx/lru
v0.14.0
Published
LruCache implementations with O(1) complexity
Maintainers
s.vanvelthemReadme
@httpx/lru
LRU cache optimized for performance and low memory usage. 2x-4x times faster on get() than quick-lru
without memory overhead and 6 times smaller than
lru-cache. TimeLru is less than 700b. Lru less than 600b.
Install
$ npm install @httpx/lru
$ yarn add @httpx/lru
$ pnpm add @httpx/lruFeatures
- 🖖 Provides LruCache and TimeLruCache.
- 🚀 Fast
cache.get()in O(1) thx to doubly linked list. - 🦆 Expose
getOrSet()method to simplify cache usage patterns. - ✨ Provides convenience helpers to preserve single instance across your app.
- 📐 Lightweight (starts at ~600B)
- 🛡️ Tested on node 20-26, browser, bun, cloudflare, deno and runtime/edge.
- 🗝️ Available in ESM and CJS formats.
Documentation
TimeLruCache
TimeLruCache allows to work with expiry time (TTL). Time-to-live are expressed in milliseconds. The API is similar to LruCache.
| Method | Description |
|----------------------------------------------| ------------------------------------------------------------------------- |
| set(key, value, ttl?): boolean | Add a new entry and return true if entry was overwritten |
| get(key): TValue \| undefined | Retrieve an entry if exists and hasn't expired. |
| has(key): boolean | Check if an entry exist and hasn't expired |
| delete(key): boolean | Remove an entry, returns bool indicating if the entry was existing |
| getOrSet(key, valueOrFn, options?): TValue | Return the entry if exists otherwise save a new entry (value or callback) |
| clear(): number | Clear the cache and return the actual number of deleted entries |
TimeLruCache.getOrSet()
Get an item from the cache, if the item doesn't exist or has expired it will create a new entry with the provided value or function and returns it.
In case of a new entry (key either doesn't exist or has expired):
- the provided value or the result of the function will be used as value.
- it will be marked as most recently used.
- an eviction will be triggered if the maximum capacity is reached
In case the item exists and hasn't expired:
- the existing value will be returned.
- it will be marked as most recently used.
- the provider function is ignored and won't be executed
const lru = new TimeLruCache({ maxSize: 2, defaultTTL: 30_000 });
// The key exists and hasn't expired
lru.set("key1", "value1");
lru.getOrSet("key1", () => "value2"); // 👈 returns 'value1' (entry exists)
// The key doesn't exist, a new entry will be created from the function return value
lru.getOrSet("key2", () => "value2", {
ttl: 2_000,
forceRevalidate: false, // default
}); // 👈 returns 'value2'
lru.has("key2"); // 👈 true (it was added)
lru.get("key1"); // 👈 'value1'
// Will trigger an eviction as maxSize capacity (2) is reached.
lru.getOrSet("key3", () => "value3"); // 👈 returns 'value3'
lru.get("key1"); // 👈 undefined (first entry was evicted)TimeLruCache.has()
Checks whether an entry exist and hasn't expired. If the entry exists but has expired, it will be removed
automatically and trigger the onEviction callback if present.
import { TimeLruCache } from "@httpx/lru";
const oneSecondInMillis = 1000;
// 👉 As an alternative to constructor, consider using the helper
// `getOrCreateTimeLruCache` to ensure only one instance is created
const lru = new TimeLruCache({
maxSize: 1,
defaultTTL: oneSecondInMillis,
onEviction: () => {
console.log("evicted");
},
});
lru.set("key0", "value0", 2 * oneSecondInMillis);
// 👇 Will evict key0 as maxSize is 1
lru.set("key1", "value1", 2 * oneSecondInMillis);
lru.has("key0"); // 👈 false (item does not exists)
lru.has("key1"); // 👈 true (item is present and is not expired)
const value = lru.get("key1"); // 👈 'value1' (item is present and is not expired)
// 🕛 wait 3 seconds, time for the item to expire
lru.has("key1"); // 👈 false (item is present but expired - 👋 onEviction will be called)LruCache
LruCache provides a base LRU implementation. It is a simple cache with a fixed capacity.
When the cache is full, the least recently used item is removed. Under the hood it uses
a doubly linked list implementation to allow get() in O(1). If you're looking for a cache with
expiry time (TTL) consider using TimeLruCache instead.
API
| Method | Description |
| ---------------------------------- | ------------------------------------------------------------------ |
| set(key, value): boolean | Add a new entry and return true if entry was overwritten |
| get(key): TValue \| undefined | Retrieve a cache entry by key |
| has(key): boolean | Check if an entry exist |
| delete(key): boolean | Remove an entry, returns bool indicating if the entry was existing |
| getOrSet(key, valueOrFn): TValue | Return the entry if exists otherwise save a new entry |
| clear(): number | Clear the cache and return the actual number of deleted entries |
Usage
// bundle size: ~550B
import { LruCache } from "@httpx/lru";
// 👉 As an alternative to constructor, consider using the helper
// `getOrCreateLruCache` to ensure only one instance is created
const lru = new LruCache({ maxSize: 1000 });
lru.set("🦆", ["cool", "stuff"]);
if (lru.has("🦆")) {
console.log(lru.get("🦆"));
// ['cool', 'stuff']
}
lru.delete("🦆");
lru.clear();Helpers
As an alternative to using the constructors directly, the package provides helpers to ensure only one instance
of LruCache or TimeLruCache is created for a given name. This is particularly useful for hybrid application such as NextJs
that might loose their references due to their specific module loading strategy. Under the hood instances are
preserved on globalThis.
getOrCreateLruCache
import { getOrCreateLruCache } from "@httpx/lru";
const ttlLru = getOrCreateLruCache("main-cache", { maxSize: 500 });getOrCreateTimeLruCache
import { getOrCreateTimeLruCache } from "@httpx/lru";
const ttlLru = getOrCreateTimeLruCache("main-cache", {
maxSize: 500,
defaultTTL: 60000,
});API
Iterable
import { LruCache } from "@httpx/lru";
const lru = new LruCache({ maxSize: 2 });
// 👇 Fill the cache with 3 entries
lru.set("key1", "value1");
lru.set("key2", "value2");
lru.set("key3", "value3"); // 👈 Will evict key1 as maxSize is 2
lru.get("key2"); // 👈 Trigger a get to move key2 to the head
const results = [];
// 🖖 Iterate over the cache entries
for (const [key, value] of lru) {
results.push([key, value]);
}
expect(results).toStrictEqual([
["key3", "value3"], // 👈 Least recently used first
["key2", "value2"], // 👈 Most recently used last
]);Callbacks
onEviction callback
Can be useful to clean up resources or trigger side effects. onEviction callback is called right before an entry is evicted.
const fn = vi.fn();
const lru = new LruCache({
maxSize: 2,
onEviction: (key, value) => {
fn(key, value);
},
});
lru.set("key1", "value1");
lru.set("key2", "value2");
lru.set("key3", "value3"); // 👈 Will evict key1 due to capacity
expect(fn).toHaveBeenCalledExactlyOnceWith("key1", "value1");Benchmarks
Performance is continuously monitored thanks to codspeed.io.
Node 24
RUN v4.1.5 /home/sebastien/github/httpx/packages/lru
✓ bench/compare/lru-cache/eviction.bench.ts > LruCache.set() 1000 items / maxSize: 500 4270ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru.set() - ts files (dev) 8,164.50 0.0748 1.1611 0.1225 0.1332 0.3879 0.5215 0.8232 ±1.58% 4083
· @httpx/lru.set() - compiled (dist) 5,154.25 0.0642 5.1284 0.1940 0.2381 0.5406 0.7064 4.7523 ±3.94% 2578
· @httpx/time-lru.set() - ts file (dev) 4,765.06 0.1146 7.9617 0.2099 0.2292 0.5678 0.6428 2.2445 ±4.67% 2383
· @httpx/time-lru.set() - compiled (dist) 5,136.00 0.1049 7.6689 0.1947 0.2099 0.5983 0.6783 1.7387 ±4.40% 2568
· [email protected]() 10,552.56 0.0721 1.1122 0.0948 0.0974 0.2605 0.3649 0.7174 ±1.32% 5277
· [email protected]() 6,340.02 0.1020 13.0768 0.1577 0.1615 0.4104 0.5492 1.4058 ±5.82% 3171
· [email protected](/with ttl/) 5,705.81 0.1062 8.6892 0.1753 0.1893 0.5313 0.7838 1.4431 ±3.92% 2853
✓ bench/compare/lru-cache/get.bench.ts > LruCache.get() - 1000 items / maxSize: 1000 3730ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru.get() - ts files (dev) 41,351.14 0.0191 1.5688 0.0242 0.0232 0.0650 0.0914 0.1717 ±0.95% 20676
· @httpx/lru.get() - compiled (dist) 39,400.57 0.0194 0.5370 0.0254 0.0263 0.0757 0.1092 0.2226 ±0.83% 19701
· @httpx/time-lru.get() - ts files (dev) 13,219.86 0.0584 1.0197 0.0756 0.0826 0.1952 0.2641 0.5732 ±1.15% 6610
· @httpx/time-lru.get() - compiled (dist) 13,997.13 0.0573 0.9274 0.0714 0.0744 0.1690 0.2416 0.4840 ±1.03% 7000
· [email protected]() 6,597.95 0.1047 1.7666 0.1516 0.1608 0.4299 0.6131 1.0933 ±1.81% 3299
· [email protected]() 26,409.39 0.0264 1.1150 0.0379 0.0401 0.1224 0.1748 0.4350 ±1.37% 13205
✓ bench/compare/lru-cache/set.bench.ts > LruCache.set() 1000 items / maxSize: 1000 3106ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru.set() - ts files (dev) 31,205.40 0.0244 0.7861 0.0320 0.0338 0.0884 0.1266 0.2758 ±0.96% 15603
· @httpx/lru.set() - compiled (dist) 28,099.26 0.0253 0.9939 0.0356 0.0384 0.1053 0.1380 0.2679 ±1.06% 14050
· @httpx/time-lru.set() - compiled (dist) 11,239.33 0.0660 1.6308 0.0890 0.0975 0.2358 0.2958 0.6727 ±1.32% 5620
· [email protected]() 15,958.05 0.0396 1.1708 0.0627 0.0678 0.2002 0.5235 0.8776 ±1.96% 7980
· [email protected]() 12,827.77 0.0582 1.3904 0.0780 0.0814 0.2157 0.3121 0.6490 ±1.34% 6414
✓ bench/compare/lru-cache/iterate.bench.ts > LruCache iterator - 1000 items 2451ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru - forEach - ts files (dev) 19,766.95 0.0312 8.3407 0.0506 0.0534 0.1671 0.3045 0.5319 ±3.61% 9884
· @httpx/lru - forEach - compiled (dist) 20,465.83 0.0316 3.4000 0.0489 0.0488 0.1723 0.3159 0.5197 ±1.93% 10233
· [email protected] - forEach 7,865.58 0.1003 2.6077 0.1271 0.1234 0.4546 0.5854 1.2174 ±1.97% 3936
· [email protected] - forEach 11,708.66 0.0610 0.9167 0.0854 0.0872 0.2956 0.4017 0.6261 ±1.42% 5855
✓ bench/compare/lru-cache/peek.bench.ts > LruCache.peek() - 1000 items / maxSize: 1000 2537ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru.peek() - ts files (dev) 85,317.30 0.0094 0.6308 0.0117 0.0117 0.0352 0.0546 0.1219 ±0.76% 42659
· @httpx/lru.peek() - compiled (dist) 85,178.41 0.0095 0.7511 0.0117 0.0125 0.0334 0.0508 0.1157 ±0.76% 42590
· [email protected]() 12,240.64 0.0621 1.0724 0.0817 0.0865 0.1857 0.2432 0.5161 ±1.09% 6121
· [email protected]() 36,763.90 0.0171 1.1830 0.0272 0.0293 0.0962 0.1333 0.3213 ±1.29% 18382
BENCH Summary
[email protected]() - bench/compare/lru-cache/eviction.bench.ts > LruCache.set() 1000 items / maxSize: 500
1.29x faster than @httpx/lru.set() - ts files (dev)
1.66x faster than [email protected]()
1.85x faster than [email protected](/with ttl/)
2.05x faster than @httpx/lru.set() - compiled (dist)
2.05x faster than @httpx/time-lru.set() - compiled (dist)
2.21x faster than @httpx/time-lru.set() - ts file (dev)
@httpx/lru.get() - ts files (dev) - bench/compare/lru-cache/get.bench.ts > LruCache.get() - 1000 items / maxSize: 1000
1.05x faster than @httpx/lru.get() - compiled (dist)
1.57x faster than [email protected]()
2.95x faster than @httpx/time-lru.get() - compiled (dist)
3.13x faster than @httpx/time-lru.get() - ts files (dev)
6.27x faster than [email protected]()
@httpx/lru - forEach - compiled (dist) - bench/compare/lru-cache/iterate.bench.ts > LruCache iterator - 1000 items
1.04x faster than @httpx/lru - forEach - ts files (dev)
1.75x faster than [email protected] - forEach
2.60x faster than [email protected] - forEach
@httpx/lru.peek() - ts files (dev) - bench/compare/lru-cache/peek.bench.ts > LruCache.peek() - 1000 items / maxSize: 1000
1.00x faster than @httpx/lru.peek() - compiled (dist)
2.32x faster than [email protected]()
6.97x faster than [email protected]()
@httpx/lru.set() - ts files (dev) - bench/compare/lru-cache/set.bench.ts > LruCache.set() 1000 items / maxSize: 1000
1.11x faster than @httpx/lru.set() - compiled (dist)
1.96x faster than [email protected]()
2.43x faster than [email protected]()
2.78x faster than @httpx/time-lru.set() - compiled (dist)Bun 1.3.13
RUN v4.1.5 /home/sebastien/github/httpx/packages/lru
✓ bench/compare/lru-cache/eviction.bench.ts > LruCache.set() 1000 items / maxSize: 500 4421ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru.set() - ts files (dev) 1,197.53 0.0790 14.9795 0.8351 1.3871 5.1009 8.9362 14.9795 ±11.75% 600
· @httpx/lru.set() - compiled (dist) 1,320.89 0.0787 198.40 0.7571 0.4753 4.6996 14.4950 198.40 ±69.83% 748
· @httpx/time-lru.set() - ts file (dev) 1,372.69 0.1298 24.0526 0.7285 1.1515 3.7973 5.4988 24.0526 ±12.14% 687
· @httpx/time-lru.set() - compiled (dist) 2,319.70 0.1211 16.8465 0.4311 0.2664 3.2391 5.8338 14.2897 ±12.01% 1160
· [email protected]() 7,782.81 0.0815 9.0347 0.1285 0.1104 0.3599 0.9572 6.3448 ±8.65% 3892
· [email protected]() 2,182.94 0.1220 22.3550 0.4581 0.2988 2.4610 13.2837 15.6275 ±16.71% 1119
· [email protected](/with ttl/) 2,942.14 0.1173 16.6449 0.3399 0.2224 2.3414 6.0788 14.9192 ±13.94% 1497
✓ bench/compare/lru-cache/get.bench.ts > LruCache.get() - 1000 items / maxSize: 1000 3735ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru.get() - ts files (dev) 31,637.83 0.0244 0.6594 0.0316 0.0309 0.0895 0.1195 0.2390 ±0.80% 15820
· @httpx/lru.get() - compiled (dist) 29,521.29 0.0279 0.6894 0.0339 0.0336 0.0895 0.1187 0.2856 ±0.87% 14761
· @httpx/time-lru.get() - ts files (dev) 14,453.53 0.0559 1.3792 0.0692 0.0737 0.1803 0.2438 0.4244 ±1.12% 7227
· @httpx/time-lru.get() - compiled (dist) 15,003.41 0.0567 0.6732 0.0667 0.0642 0.1652 0.2276 0.4673 ±0.96% 7503
· [email protected]() 5,764.77 0.1054 6.4383 0.1735 0.1949 0.4753 0.5875 4.7629 ±4.32% 2883
· [email protected]() 18,771.88 0.0321 7.5666 0.0533 0.0600 0.1750 0.2274 0.4515 ±3.62% 9386
✓ bench/compare/lru-cache/set.bench.ts > LruCache.set() 1000 items / maxSize: 1000 3132ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru.set() - ts files (dev) 28,910.77 0.0286 0.6597 0.0346 0.0339 0.0875 0.1218 0.2933 ±0.85% 14456
· @httpx/lru.set() - compiled (dist) 28,137.41 0.0303 0.7425 0.0355 0.0330 0.0882 0.1278 0.3447 ±0.93% 14069
· @httpx/time-lru.set() - compiled (dist) 15,242.75 0.0570 2.1758 0.0656 0.0645 0.1456 0.2023 0.4559 ±1.20% 7622
· [email protected]() 12,044.40 0.0478 5.8957 0.0830 0.0780 0.3275 0.3754 4.4128 ±5.82% 6023
· [email protected]() 12,749.64 0.0547 3.3271 0.0784 0.0873 0.2146 0.2990 0.7256 ±2.21% 6375
✓ bench/compare/lru-cache/peek.bench.ts > LruCache.peek() - 1000 items / maxSize: 1000 2542ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru.peek() - ts files (dev) 87,391.64 0.0086 0.5211 0.0114 0.0106 0.0313 0.0541 0.1399 ±0.79% 43696
· @httpx/lru.peek() - compiled (dist) 77,536.90 0.0105 1.3749 0.0129 0.0110 0.0356 0.0578 0.1300 ±0.95% 38769
· [email protected]() 18,065.03 0.0473 1.0166 0.0554 0.0559 0.1335 0.1819 0.3078 ±0.85% 9033
· [email protected]() 28,496.70 0.0186 7.6128 0.0351 0.0390 0.1330 0.1789 0.4001 ±3.90% 14249
✓ bench/compare/lru-cache/iterate.bench.ts > LruCache iterator - 1000 items 2516ms
name hz min max mean p75 p99 p995 p999 rme samples
· @httpx/lru - forEach - ts files (dev) 22,130.73 0.0211 12.2012 0.0452 0.0411 0.1848 0.2452 0.7212 ±7.13% 11066
· @httpx/lru - forEach - compiled (dist) 28,602.83 0.0211 7.4535 0.0350 0.0331 0.1028 0.1327 0.3496 ±6.45% 14436
· [email protected] - forEach 10,469.20 0.0684 6.3822 0.0955 0.0941 0.2649 0.3710 1.2177 ±4.90% 5235
· [email protected] - forEach 17,421.94 0.0386 6.6090 0.0574 0.0608 0.1614 0.2096 0.5616 ±4.49% 8711
BENCH Summary
@httpx/lru.set() - ts files (dev) - bench/compare/lru-cache/set.bench.ts > LruCache.set() 1000 items / maxSize: 1000
1.03x faster than @httpx/lru.set() - compiled (dist)
1.90x faster than @httpx/time-lru.set() - compiled (dist)
2.27x faster than [email protected]()
2.40x faster than [email protected]()
@httpx/lru.peek() - ts files (dev) - bench/compare/lru-cache/peek.bench.ts > LruCache.peek() - 1000 items / maxSize: 1000
1.13x faster than @httpx/lru.peek() - compiled (dist)
3.07x faster than [email protected]()
4.84x faster than [email protected]()
[email protected]() - bench/compare/lru-cache/eviction.bench.ts > LruCache.set() 1000 items / maxSize: 500
2.65x faster than [email protected](/with ttl/)
3.36x faster than @httpx/time-lru.set() - compiled (dist)
3.57x faster than [email protected]()
5.67x faster than @httpx/time-lru.set() - ts file (dev)
5.89x faster than @httpx/lru.set() - compiled (dist)
6.50x faster than @httpx/lru.set() - ts files (dev)
@httpx/lru - forEach - compiled (dist) - bench/compare/lru-cache/iterate.bench.ts > LruCache iterator - 1000 items
1.29x faster than @httpx/lru - forEach - ts files (dev)
1.64x faster than [email protected] - forEach
2.73x faster than [email protected] - forEach
@httpx/lru.get() - ts files (dev) - bench/compare/lru-cache/get.bench.ts > LruCache.get() - 1000 items / maxSize: 1000
1.07x faster than @httpx/lru.get() - compiled (dist)
1.69x faster than [email protected]()
2.11x faster than @httpx/time-lru.get() - compiled (dist)
2.19x faster than @httpx/time-lru.get() - ts files (dev)
5.49x faster than [email protected]()See benchmark file for details.
Bundle size
Bundle size is tracked by a size-limit configuration
| Scenario (esm) | Size (brotli) |
| ----------------------------------------------------- | ------------: |
| import { LruCache } from '@httpx/lru | ~ 570B |
| import { TimeLruCache } from '@httpx/lru | ~ 670B |
| import { getOrCreateLruCache } from '@httpx/lru | ~ 695B |
| import { getOrCreateTimeLruCache } from '@httpx/lru | ~ 750B |
For CJS usage (not recommended) track the size on bundlephobia.
Compatibility
| Level | CI | Description | |--------------| --- |--------------------------------------------------------------------------------------------------------------------------------------------------| | Node | ✅ | CI for 20.x, 22.x, 24.x & 26.x. | | Browser | ✅ | Tested with latest chrome (vitest/playwright) | | Browserslist | ✅ | defaults, > 0.26%, last 2 versions, Firefox ESR, not dead | | Bun | ✅ | Tested with latest (at time of writing >= 1.3.3) | | Deno | ✅ | Tested with latest lts | | Edge | ✅ | Ensured on CI with @vercel/edge-runtime. | | Cloudflare | ✅ | Ensured with @cloudflare/vitest-pool-workers (see wrangler.toml | | Typescript | ✅ | TS 5.0 + / are-the-type-wrong checks on CI. | | ES2022 | ✅ | Dist files checked with es-check | | Performance | ✅ | Monitored with codspeed.io |
For older browsers: most frontend frameworks can transpile the library (ie: nextjs...)
Comparison with other libraries
| Name | Import | Size | (gzip) | BundleJs |
| ---------- | ------------------ | -------: | ------: | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| @httpx/lru | { LruCache } | 1.49 KB | 0.65 KB | |
| @httpx/lru |
{ TimeLruCache } | 1.91 KB | 0.78 KB | |
| lru-cache |
{ LruCache } | 17.30 KB | 5.71 KB | |
| quick-lru |
{ default } | 3.36 KB | 1.17 KB | |
Contributors
Contributions are welcome. Have a look to the CONTRIBUTING document.
Sponsors
If my OSS work brightens your day, let's take it to new heights together! Sponsor, coffee, or star – any gesture of support fuels my passion to improve. Thanks for being awesome! 🙏❤️
Special thanks to
License
MIT © Sébastien Vanvelthem and contributors.