# `LatticeStripe.Billing.MeterErrorReport.ErrorType`
[🔗](https://github.com/szTheory/lattice_stripe/blob/v2.2.2/lib/lattice_stripe/billing/meter_error_report/error_type.ex#L1)

One class of async meter-event failure: a `code`, how many events failed with
it, and a **sample** of those failures.

## `sample_errors` is a sample, not a list of every failure

`error_count` is the true number of events that failed with this `code`.
`sample_errors` holds only a subset Stripe chose to include — and on
high-volume failures it is routinely empty while `error_count` is in the
hundreds. Treating `length(sample_errors)` as the failure count under-reports,
usually by an order of magnitude. Read `error_count` for the count and
`sample_errors` for the examples.

## `code` is a String, and stays one

`code` is **never** converted to an atom. Three reasons, each sufficient:

1. **Stripe documents the enum as open.** The reference says "Open Enum."
   verbatim. New values arrive without a version bump.
2. **It is server-controlled and demonstrably growing.** Stripe has already
   *retired* one value (`meter_event_value_not_found`) that this repository's
   own metering guide still documents — the set churns in both directions.
3. **Atoms are never garbage collected on the BEAM.** Atomizing a value an
   external server chooses is an atom-table exhaustion vector, and the
   existing-atom variant merely converts that vector into a decode crash on
   the next code Stripe adds.

A closed union type would go stale the same way the Elixir peer library's
card-error union did. Match on the binary.

## Current values (non-exhaustive)

The ten values Stripe publishes today. This list is documentation, not a
contract — do not build a total `case` over it without a catch-all clause:

- `"archived_meter"`
- `"meter_event_customer_not_found"`
- `"meter_event_dimension_count_too_high"`
- `"meter_event_invalid_value"`
- `"meter_event_no_customer_defined"`
- `"meter_event_value_too_many_digits"`
- `"missing_dimension_payload_keys"`
- `"no_meter"`
- `"timestamp_in_future"`
- `"timestamp_too_far_in_past"`

Note that `"no_meter"` (a **code**) is a different thing from
`v1.billing.meter.no_meter_found` (an **event type**).

# `t`

```elixir
@type t() :: %LatticeStripe.Billing.MeterErrorReport.ErrorType{
  code: String.t() | nil,
  error_count: integer() | nil,
  sample_errors: [LatticeStripe.Billing.MeterErrorReport.SampleError.t()]
}
```

# `from_map`

```elixir
@spec from_map(map() | nil) :: t() | nil
```

Decode one wire `error_types[]` entry.

`from_map(nil)` returns `nil`. An absent or empty `sample_errors` array
yields `[]` — never `nil`, so callers can comprehend over it unconditionally.

---

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