errors.go

package switchos

import (
	"errors"
	"fmt"
)

// ErrUnsupported is returned when a requested operation or whole endpoint
// isn't supported by the connected device's board (e.g. GetPoe on
// BoardCSS318G, which has no PoE hardware). Individual fields that a
// board doesn't support are simply left nil in the returned struct
// instead of returning an error.
var ErrUnsupported = errors.New("switchos: operation not supported on this board")

// StatusError is returned when a SwOS device responds with a non-200
// HTTP status, or with a 200 status but no decodable JSON body (which
// happens on some devices/firmware when hitting an endpoint that isn't
// actually implemented - see the RB260GS v1.17 firmware caveat in the
// README).
type StatusError struct {
	StatusCode int
	Body       []byte
}

func (e *StatusError) Error() string {
	return fmt.Sprintf("switchos: unexpected response (status %d): %s", e.StatusCode, e.Body)
}

func checkResponse(statusCode int, body []byte, json200 bool) error {
	if statusCode != 200 {
		return &StatusError{StatusCode: statusCode, Body: body}
	}
	if !json200 {
		return &StatusError{StatusCode: statusCode, Body: body}
	}
	return nil
}

// NameTooLongError is returned by PutLink/PutVlan when a name field
// (e.g. Link.Name, VlanEntry.Name) exceeds the connected board's
// firmware limit (see MaxNameLength). Without this check, an overlong
// name is silently truncated by the device instead of rejected, which
// otherwise only surfaces several layers away as a confusing "Provider
// produced inconsistent result after apply" error in Terraform.
type NameTooLongError struct {
	Board     Board
	Field     string
	Name      string
	MaxLength int
}

func (e *NameTooLongError) Error() string {
	return fmt.Sprintf(
		"switchos: %s %q is %d bytes long, but board %s allows at most %d bytes - the device would silently truncate it",
		e.Field, e.Name, len(e.Name), e.Board, e.MaxLength,
	)
}