LatticeStripe.Webhook.CacheBodyReader (LatticeStripe v2.2.0)

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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.

Summary

Functions

read_body(conn, opts)

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

Functions

read_body(conn, opts)

@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.