# `Teya.Reversal`
[🔗](https://github.com/sgerrand/ex_teya/blob/v0.4.0/lib/teya/reversal.ex#L1)

Void a transaction before settlement.

A reversal cancels a transaction that has not yet settled with the card
network. For transactions that have already settled, use `Teya.Refund`
instead.

Required OAuth scope: `reversals/create`.

# `create`

```elixir
@spec create(
  map(),
  keyword()
) :: {:ok, map()} | {:error, Teya.Error.t()}
```

Creates a reversal.

Either `transaction_id` or `idempotency_key` (the key from the original
transaction request) must be included in `params` to identify the transaction.

Returns `{:ok, response}` where `response["status"]` is `"SUCCESS"`,
`"FAILURE"`, `"PENDING"`, or `"ACKNOWLEDGED"`. An `"ACKNOWLEDGED"` response
(HTTP 202) means the reversal has been accepted but processing is not yet
complete.

## Required params

- `reversal_reason` — `"CARD_REVERSAL"`, `"CARD_REMOVED"`, or
  `"COMMUNICATION_REVERSAL"`

One of:
- `transaction_id` — ID of the transaction to reverse
- `idempotency_key` — idempotency key used when creating the original transaction

## Options

- `idempotency_key` — override the auto-generated idempotency key for *this*
  reversal request (distinct from the `idempotency_key` body field used to
  reference the original transaction)

## Examples

    {:ok, response} = Teya.Reversal.create(%{
      "reversal_reason" => "CARD_REVERSAL",
      "transaction_id"  => transaction_id
    })

    response["status"]           # "SUCCESS" | "FAILURE" | "PENDING" | "ACKNOWLEDGED"
    response["reversal_amount"]  # %{"amount" => 1000, "currency" => "GBP"}

---

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