Invalidation

Invalidation removes cached entries after data changes. Layeron Cache supports single-entry deletes and grouped purges.

Delete One Entry

Use delete(request) when you know the exact request to remove:

await apiCache.delete("https://api.example.com/api/products")

If the original entry used custom vary headers, pass the same vary options:

await apiCache.delete(request, {
  vary: ["accept-language"],
})

delete returns true when Cloudflare Cache reports that an entry was removed.

Purge by Request

Use purge({ request }) when a workflow already works with purge objects:

const result = await apiCache.purge({
  request: "https://api.example.com/api/products",
})

The result includes the count of removed entries:

{ "purged": 1 }

Purge by Tag

Tag purges are the most common application workflow:

await apiCache.put(request, response.clone(), {
  tags: ["products", "product:123"],
})

await apiCache.purge({
  tags: ["product:123"],
})

Use broad and precise tags together:

Tag	Purpose
products	Purge product list pages after bulk imports.
product:123	Purge one product detail page after editing it.
tenant:acme	Purge public tenant-scoped content after tenant changes.
cms:home	Purge a specific CMS page or slot.

Purge by Prefix

Prefix purges target keys that begin with a prefix:

await apiCache.purge({
  prefix: "https://api.example.com/api/products",
})

Prefix purges use Cache metadata stored in the internal Database product. They are useful for grouped URL structures such as /api/docs/ or /api/catalog/.

Invalidate After Writes

Write routes should purge the entries affected by the change:

app.post("/api/products/:id", async (request) => {
  const pathSegments = new URL(request.url).pathname.split("/")
  const id = pathSegments[3]
  const input = await request.json()

  await updateProduct(id, input)
  await apiCache.purge({
    tags: ["products", `product:${id}`],
  })

  return Response.json({ ok: true })
})

For webhook-driven content updates, purge inside the webhook handler after the event has been validated and persisted.

Choosing an Invalidation Strategy

Strategy	Use When
Delete by request	You can reconstruct one exact request key.
Purge by request	You want a consistent purge(...) call shape.
Purge by tag	Multiple URLs share the same data dependency.
Purge by prefix	URLs share a predictable path prefix.

Prefer tags for application data. Tags express the relationship between cached responses and the data that can invalidate them.