plugins

type AgentHandler interface {
	// If the plugin doesn't handle the request, it should return false.
	HandleAgentRequest(w http.ResponseWriter, r *http.Request) bool
}

type BaseSpec struct {
	NameField string `json:"name"`
	KindField string `json:"kind"`
}

type Constructor struct {
	// Kind is the kind of the plugin.
	Kind string

	// DefaultSpec returns a default spec for the plugin, with default values.
	// The function should always return a new spec copy, since it will be
	// modified and used by next moves.
	//
	// NOTE1: The DefaultSpec must returns complete spec (including name) for system plugins.
	DefaultSpec func() Spec

	// SystemPlugin being true value indicates the plugin is system-level,
	// which means it will always be loaded even if not specified in the config.
	SystemPlugin bool

	// NewInstance creates a new plugin instance for the kind.
	// NOTE: The spec has the same type with the one which DefaultSpec returns.
	NewInstance func(spec Spec) (Plugin, error)
}

type ConstructorsByKind []*Constructor

type HTTPDoer interface {
	Do(req *http.Request) (*http.Response, error)
}

type Plugin interface {
	Close() error
	Name() string
}

type Spec interface {
	// Name returns name.
	Name() string

	// Kind returns kind.
	Kind() string

	// Validate validates the spec.
	Validate() error
}

type UserClientRequestWrapper interface {
	WrapUserClientRequest(parent context.Context, req *http.Request) *http.Request
}

type UserClientWrapper interface {
	WrapUserClient(client HTTPDoer) HTTPDoer
}

type UserHandlerFuncWrapper interface {
	// If the plugin doesn't wrap the user handler, it should not implement this method.
	WrapUserHandlerFunc(fn http.HandlerFunc) http.HandlerFunc
}