README
shm-lru-cache
A cache object that deletes the least-recently-used items.
Installation:
npm install shm-lru-cache --save
Usage:
// node.js exposition
Options
max
The maximum size of the cache, checked by applying the length function to all values in the cache. Not setting this is kind of silly, since that's the whole purpose of this lib, but it defaults toInfinity
.maxAge
Maximum age in ms. Items are not pro-actively pruned out as they age, but if you try to get an item that is too old, it'll drop it and return undefined instead of giving it to you.record_size
API
set(key, value, maxAge)
get(key) => value
Both of these will update the "recently used"-ness of the key. They do what you think.
maxAge
is optional and overrides the cachemaxAge
option if provided.If the key is not found,
get()
will returnundefined
.The key and val can be any value.
peek(key)
Returns the key value (or
undefined
if not found) without updating the "recently used"-ness of the key.(If you find yourself using this a lot, you might be using the wrong sort of data structure, but there are some use cases where it's handy.)
del(key)
Deletes a key out of the cache.
reset()
Clear the cache entirely, throwing away all values.
has(key)
Check if a key is in the cache, without updating the recent-ness or deleting it for being stale.
keys()
Return an array of the keys in the cache.
values()
Return an array of the values in the cache.
length
Return total length of objects in cache taking into account
length
options function.itemCount
Return total quantity of objects currently in cache. Note, that
stale
(see options) items are returned as part of this item count.dump()
Return an array of the cache entries ready for serialization and usage with 'destinationCache.load(arr)`.
load(cacheEntriesArray)
this is a test
prune()
Manually iterates over the entire cache proactively pruning old entries