Miniflare sets CF-Cache-Status to null on misses

[aeneasr]

Contrary to cloudflare's behavior, miniflare does not set CF-Cache-Status when the cache was a miss.

Cloudflare however returns the header with MISS:

CF-Cache-Status: miss

[mrbbot]

Hey! 👋 Could I clarify, is this when using the fetch API? Or the caches API? Would you be able to provide the code snippet where you're seeing this? Miniflare does not support cache with fetch, so this is potentially why you're seeing this.

[aeneasr]

Hey, sorry for being so sparse on detail in this issue. The code is essentially:

export async function handleRequest(request: Request, ctx: ExecutionContext) {
  // ... cache key computation ...

  // Try to fetch the item from the cache
  const cache = caches.default
  let response

  response = await cache.match(cacheKey)

  if (!response) {
    response = await fetchAndPotentiallyCache({
      request,
      cacheKey,
      ctx,
    })
  }

  response = new Response(response.body, response)

  // Done
  return response
}

export async function fetchAndPotentiallyCache({
  request,
  cacheKey,
  ctx,
}: {
  request: Request
  cacheKey: string
  ctx: ExecutionContext
}): Promise<Response> {
  let response = await fetch(request, {
    cf: {
      cacheEverything: true
    },
  })

  response = new Response(response.body, response)
  response.headers.set(
    "Cache-Control",
    `s-maxage=60`,
  )

  // This is a small workaround for miniflare
  // TODO remove once https://github.com/cloudflare/miniflare/issues/82 is fixed
  const cloned = response.clone()
  ctx.waitUntil(
    caches.default
      .delete(cacheKey)
      .then(() => caches.default.put(cacheKey, cloned)),
  )

  return response
}

When we get a cache hit in cache.match, the header is set to CF-Cache-Status: hit. If not, the header is unset.

[mrbbot]

Hey! 👋 Apologies for the delayed follow up. I'm going to transfer this to workers-sdk as that's the new home for Miniflare 3, and that will make it easier for us to track this. 👍