Files
medusa-store/packages/modules/cache-inmemory/src/services/inmemory-cache.ts
2024-09-26 11:14:35 +05:30

107 lines
2.5 KiB
TypeScript

import { ICacheService } from "@medusajs/framework/types"
import { CacheRecord, InMemoryCacheModuleOptions } from "../types"
const DEFAULT_TTL = 30 // seconds
type InjectedDependencies = {}
/**
* Class represents basic, in-memory, cache store.
*/
class InMemoryCacheService implements ICacheService {
protected readonly TTL: number
protected readonly store = new Map<string, CacheRecord<any>>()
protected readonly timoutRefs = new Map<string, NodeJS.Timeout>()
constructor(
deps: InjectedDependencies,
options: InMemoryCacheModuleOptions = {}
) {
this.TTL = options.ttl ?? DEFAULT_TTL
}
/**
* Retrieve data from the cache.
* @param key - cache key
*/
async get<T>(key: string): Promise<T | null> {
const now = Date.now()
const record: CacheRecord<T> | undefined = this.store.get(key)
const recordExpire = record?.expire ?? Infinity
if (!record || recordExpire < now) {
return null
}
return record.data
}
/**
* Set data to the cache.
* @param key - cache key under which the data is stored
* @param data - data to be stored in the cache
* @param ttl - expiration time in seconds
*/
async set<T>(key: string, data: T, ttl: number = this.TTL): Promise<void> {
if (ttl === 0) {
return
}
const record: CacheRecord<T> = { data, expire: ttl * 1000 + Date.now() }
const oldRecord = this.store.get(key)
if (oldRecord) {
clearTimeout(this.timoutRefs.get(key))
this.timoutRefs.delete(key)
}
const ref = setTimeout(async () => {
await this.invalidate(key)
}, ttl * 1000)
ref.unref()
this.timoutRefs.set(key, ref)
this.store.set(key, record)
}
/**
* Delete data from the cache.
* Could use wildcard (*) matcher e.g. `invalidate("ps:*")` to delete all keys that start with "ps:"
*
* @param key - cache key
*/
async invalidate(key: string): Promise<void> {
let keys = [key]
if (key.includes("*")) {
const regExp = new RegExp(key.replace("*", ".*"))
keys = Array.from(this.store.keys()).filter((k) => k.match(regExp))
}
keys.forEach((key) => {
const timeoutRef = this.timoutRefs.get(key)
if (timeoutRef) {
clearTimeout(timeoutRef)
this.timoutRefs.delete(key)
}
this.store.delete(key)
})
}
/**
* Delete the entire cache.
*/
async clear() {
this.timoutRefs.forEach((ref) => clearTimeout(ref))
this.timoutRefs.clear()
this.store.clear()
}
}
export default InMemoryCacheService