# `LatticeStripe.Webhook.CacheBodyReader`
[🔗](https://github.com/szTheory/lattice_stripe/blob/v2.2.2/lib/lattice_stripe/webhook/cache_body_reader.ex#L2)

Preserves a Stripe webhook request's exact raw body while `Plug.Parsers` reads it.

This module is available only when your application includes `:plug`; LatticeStripe
keeps the module behind an optional-Plug compile guard.

Prefer mounting `LatticeStripe.Webhook.Plug` before `Plug.Parsers` for a Stripe
endpoint. Use this reader only as an advanced alternative when endpoint ordering
cannot change and `Plug.Parsers` must run first.

Configure it as `Plug.Parsers`' `:body_reader` callback. Every successful call
returns the same tag and current chunk as `Plug.Conn.read_body/2`. After its
terminal `{:ok, body, conn}` result, `conn.private[:raw_body]` contains the exact
complete request-body binary in its original byte order.

## Retention and scope

A parser-level body reader retains another copy of each request body for the
connection lifetime. Scope it narrowly to the webhook route where possible: raw
bodies can contain PII and must not be logged wholesale. This reader is not for
multipart parsing.

# `read_body`

```elixir
@spec read_body(
  Plug.Conn.t(),
  keyword()
) ::
  {:ok, binary(), Plug.Conn.t()}
  | {:more, binary(), Plug.Conn.t()}
  | {:error, term()}
```

Reads the current request-body chunk and caches raw bytes in
`conn.private[:raw_body]`.

This function is a drop-in replacement for `Plug.Conn.read_body/2` and is
intended to be used as the `:body_reader` option for `Plug.Parsers`.

After a terminal `{:ok, body, conn}` result, `conn.private[:raw_body]` contains
the exact complete body. On `{:more, body, conn}`, the private value contains all
chunks read so far. The fixed `:raw_body` key is intentionally not configurable.

---

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