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Function: getCachedOrFetch()

getCachedOrFetch<T>(cache: TypedCache<string, T>, key: string, fetcher: () => Promise<T>, ttl?: number): Promise<T>

Defined in: src/utils/cache.ts:416

Retrieve a value from a cache or compute and store it on a cache miss.

Type Parameters​

T​

T

Type of the cached value.

Parameters​

cache​

TypedCache<string, T>

Cache instance to use for lookup and storage.

key​

string

Cache key to look up.

fetcher​

() => Promise<T>

Async function that computes or fetches the value on a cache miss.

ttl?​

number

Optional per-entry TTL in milliseconds to apply when storing the fetched value; when omitted the cache's default TTL (if any) applies.

Returns​

Promise<T>

A promise that resolves to the cached or freshly fetched value.

Remarks​

The function first attempts to read from the supplied TypedCache. If the key is absent or expired it invokes fetcher to obtain the value, stores the result in the cache (honoring an optional ttl), and returns the value. Any exception thrown by fetcher is propagated to the caller and no value is cached in that case.

Example​

const value = await getCachedOrFetch(
    AppCaches.general,
    "user:123",
    async () => {
        const resp = await apiClient.get("/user/123");
        return resp.data;
    },
    60_000
);

Throws​

Any error thrown by fetcher is propagated to the caller.