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All topics›JavaScript›Offline & storage

A cache-first lookup, the shape a service worker uses

intermediatelayer I9 · Offline & storage2 tests

Write cacheFirst(cache, network, key) — a Map stands in for the Cache API, and network is an async function standing in for a real fetch. Return the cached value if it exists; otherwise call network(key), store the result in cache, and return it.

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