# `LatticeStripe.Webhook.SignatureVerificationError`
[🔗](https://github.com/szTheory/lattice_stripe/blob/v0.2.0/lib/lattice_stripe/webhook/signature_verification_error.ex#L1)

Exception raised when Stripe webhook signature verification fails.

This exception is raised by the bang variants `LatticeStripe.Webhook.verify_signature!/3`
and `LatticeStripe.Webhook.construct_event!/3` when verification fails. The `reason`
field contains a machine-matchable atom describing why verification failed.

## Reason Atoms

- `:missing_header` — the `Stripe-Signature` header was absent or empty
- `:invalid_header` — the `Stripe-Signature` header was present but malformed (missing `t=` or `v1=`)
- `:no_matching_signature` — none of the provided secrets produced a matching HMAC
- `:timestamp_expired` — the webhook timestamp is older than the configured tolerance (default 300s)

## Example

    try do
      LatticeStripe.Webhook.construct_event!(payload, sig_header, secret)
    rescue
      e in LatticeStripe.Webhook.SignatureVerificationError ->
        IO.inspect(e.reason)  # :no_matching_signature
    end

# `t`

```elixir
@type t() :: %LatticeStripe.Webhook.SignatureVerificationError{
  __exception__: true,
  message: String.t(),
  reason: verify_error()
}
```

# `verify_error`

```elixir
@type verify_error() ::
  :missing_header
  | :invalid_header
  | :no_matching_signature
  | :timestamp_expired
```

---

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