Function Register

huma.go:711–1167

Register an operation handler for an API. The handler must be a function that takes a context and a pointer to the input struct and returns a pointer to the output struct and an error. The input struct must be a struct with fields for the request path/query/header/cookie parameters and/or body. The

(api API, op Operation, handler func(context.Context, *I) (*O, error))

//		return resp, nil
//	})
func Register[I, O any](api API, op Operation, handler func(context.Context, *I) (*O, error)) {
	oapi := api.OpenAPI()
	registry := oapi.Components.Schemas

	if op.Method == "" {
		panic("method must be specified in operation")
	}
	if op.Path == "" {
		if grp, ok := api.(*Group); !ok || len(grp.prefixes) == 0 {
			panic("path must be specified in operation")
		}
	}
	initResponses(&op)

	inputType := reflect.TypeFor[I]()
	if inputType.Kind() != reflect.Struct {
		panic("input must be a struct")
	}
	inputParams, inputBodyIndex, hasInputBody, rawBodyIndex, rbt, rawBodyDataT, inSchema := processInputType(inputType, &op, registry)

	outputType := reflect.TypeFor[O]()
	if outputType.Kind() != reflect.Struct {
		panic("output must be a struct")
	}
	outHeaders, outStatusIndex, outBodyIndex, outBodyFunc := processOutputType(outputType, &op, registry)

	if len(op.Errors) > 0 {
		if len(inputParams.Paths) > 0 || hasInputBody {
			op.Errors = append(op.Errors, http.StatusUnprocessableEntity)
		}
		op.Errors = append(op.Errors, http.StatusInternalServerError)
	}
	defineErrors(&op, registry)

	if documenter, ok := api.(OperationDocumenter); ok {
		// Enables customization of OpenAPI documentation behavior for operations.
		documenter.DocumentOperation(&op)
	} else if !op.Hidden {
		oapi.AddOperation(&op)
	}

	resolvers := findResolvers(resolverType, inputType)
	defaults := findDefaults(registry, inputType)

	// Pre-compute query parameter validation data to reduce per-request allocations.
	knownParams := make(map[string]struct{})
	var deepPrefixes []string
	for i := range inputParams.Paths {
		p := inputParams.Paths[i].Value
		if p == nil || p.Loc != "query" {
			continue
		}

		if p.Style == styleDeepObject {
			deepPrefixes = append(deepPrefixes, p.Name+"[")
			continue
		}