default.go

package restapi

import (
	"net/http"
	"sync/atomic"
)

// defaultAPI holds the package-level [API] returned by [Default]. It is an
// atomic pointer so it can be hot-swapped via [SetDefault] without locks on
// the read path.
var defaultAPI atomic.Pointer[API]

func init() {
	defaultAPI.Store(NewAPI(WithErrorRegistry(newDefaultErrorRegistry())))
}

// newDefaultErrorRegistry builds the pre-populated [ErrorRegistry] used by
// the default [API]. Its fallback is [CodeInternal] with HTTP 500, and it
// pre-registers the eight remaining standard HTTP-aligned codes. It panics
// if the static entry list is malformed, which is by construction
// unreachable for the package's own codes but catches future typos.
func newDefaultErrorRegistry() *ErrorRegistry {
	fallback := ErrorRegistryEntry{
		StatusCode: http.StatusInternalServerError,
		ErrorCode:  CodeInternal,
		Message:    "internal error",
	}

	registry, err := NewErrorRegistry(
		fallback,
		ErrorRegistryEntry{StatusCode: http.StatusBadRequest, ErrorCode: CodeBadRequest, Message: "bad request"},
		ErrorRegistryEntry{StatusCode: http.StatusUnauthorized, ErrorCode: CodeUnauthorized, Message: "unauthorized"},
		ErrorRegistryEntry{StatusCode: http.StatusForbidden, ErrorCode: CodeForbidden, Message: "forbidden"},
		ErrorRegistryEntry{StatusCode: http.StatusNotFound, ErrorCode: CodeNotFound, Message: "resource not found"},
		ErrorRegistryEntry{StatusCode: http.StatusConflict, ErrorCode: CodeConflict, Message: "conflict"},
		ErrorRegistryEntry{StatusCode: http.StatusUnprocessableEntity, ErrorCode: CodeValidationFailed, Message: "validation failed"},
		ErrorRegistryEntry{StatusCode: http.StatusTooManyRequests, ErrorCode: CodeTooManyRequests, Message: "too many requests"},
		ErrorRegistryEntry{StatusCode: http.StatusServiceUnavailable, ErrorCode: CodeUnavailable, Message: "service unavailable"},
	)

	if err != nil {
		panic(err)
	}

	return registry
}