# `ExDisco.Error`
[🔗](https://github.com/bo1ta/ex_disco/blob/main/lib/ex_disco/error.ex#L1)

Structured error information from Discogs API requests.

When a request fails, the client returns an Error struct with details about
what went wrong. The `:type` field indicates the category of error, and
`:message` provides a human-readable description.

## Error Types

- `:invalid_argument` — Bad input (wrong type, out of range, etc.)
- `:unauthorized` — Missing or invalid authentication
- `:forbidden` — Authenticated but not authorized for this resource
- `:not_found` — Resource does not exist (HTTP 404)
- `:rate_limited` — Rate limit exceeded (HTTP 429)
- `:api_error` — Other API error (HTTP 4xx or 5xx)
- `:transport_error` — Network or connection error

## Fields

- `:message` — Human-readable error description
- `:status` — HTTP status code (if applicable)
- `:type` — Error category (atom)
- `:details` — Additional error details from the API

## Examples

Handle a 404:

    case ExDisco.Artists.get(999999) do
      {:ok, artist} -> IO.inspect(artist)
      {:error, error} ->
        if error.type == :not_found do
          IO.puts("Artist not found")
        else
          IO.puts("Error: #{error.message}")
        end
    end

Handle rate limiting:

    case ExDisco.Search.query([...]) do
      {:ok, results} -> results
      {:error, %ExDisco.Error{type: :rate_limited}} ->
        Process.sleep(3000)  # Wait before retrying
        ExDisco.Search.query([...])
      {:error, error} -> {:error, error}
    end

# `t`

```elixir
@type t() :: %ExDisco.Error{
  __exception__: true,
  details: term(),
  message: String.t(),
  status: pos_integer() | nil,
  type: atom()
}
```

# `auth_required`

# `invalid_argument`

```elixir
@spec invalid_argument(String.t()) :: {:error, t()}
```

Returns an `{:error, t()}` tuple for invalid arguments.

Use this as a catch-all clause on functions with guard constraints to return
a structured error instead of raising a `FunctionClauseError`.

## Examples

    def get(id) when is_integer(id) and id > 0, do: ...
    def get(_), do: Error.invalid_argument("id must be a positive integer")

    def put_rating(_, _, rating, _) when rating not in 1..5,
      do: Error.invalid_argument("rating must be between 1 and 5")
    def put_rating(_, _, _, _), do: Error.invalid_argument()

---

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