# `Wiztchta.Store`
[🔗](https://github.com/darth-jorge/wiztcha/blob/v0.1.0/lib/wiztchta/store.ex#L1)

Behaviour for replay protection: remembers which challenge tokens were
already submitted until they expire.

The default, `Wiztchta.Store.ETS`, is started automatically and keeps
used ids in memory on the local node. In a multi-node cluster a token could
be replayed once per node; plug in a shared store (Redis, Nebulex, a
database...) to prevent that:

    config :wiztchta, store: MyApp.WiztchtaRedisStore

Set `store: nil` to disable replay protection.

# `consume`

```elixir
@callback consume(id :: String.t(), expires_at :: integer(), opts :: keyword()) ::
  :ok | {:error, :already_used}
```

Atomically marks `id` as used until `expires_at` (unix seconds).

Must return `{:error, :already_used}` if `id` was already consumed.

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*Consult [api-reference.md](api-reference.md) for complete listing*