endpoint

type ClientInfo struct {
	ID    string
	IP    string
	Model string
	Name  string
}

type ConnectInfo struct {
	Connect      bool
	ServerAddr   string
	ConnectTimes map[string]time.Duration
	Protocol     string
	TLSTime      time.Duration
	TLSVersion   string
}

type DNSEndpoint struct {
	// Addr use to contact the DNS server.
	Addr string
}

type DOHEndpoint struct {
	// Hostname use to contact the DoH server. If Bootstrap is provided,
	// Hostname is only used for TLS verification.
	Hostname string

	// Path to use with DoH HTTP requests. If empty, the path received in the
	// request by Transport is left untouched.
	Path string

	// Bootstrap is the IPs to use to contact the DoH server. When provided, no
	// DNS request is necessary to contact the DoH server. The fastest IP is
	// used.
	Bootstrap []string `json:"ips"`

	// ALPN is the list of alpn-id declared to be supported by the endpoint
	// through HTTPSSVC or Alt-Svc. If missing, h2 is assumed.
	ALPN []string
	// contains filtered or unexported fields
}

type Endpoint interface {
	fmt.Stringer

	// Protocol returns the protocol used by this endpoint to transport DNS.
	Protocol() Protocol

	// Equal returns true if e represent the same endpoint.
	Equal(e Endpoint) bool

	// Send a DNS payload and get the response in buf.
	Exchange(ctx context.Context, payload, buf []byte) (n int, err error)
}

type Manager struct {
	// Providers is a list of Endpoint providers listed in order of preference.
	// The first working provided is selected on each call to Test or internal
	// test performed on error or opportunistically.
	//
	// Calling Test with an empty Providers list will result in a panic.
	Providers []Provider

	// InitEndpoint defines the endpoint to use before Providers returned a
	// working endpoint.
	InitEndpoint Endpoint

	// ErrorThreshold is the number of consecutive errors with a endpoint
	// requires to trigger a test to fallback on another endpoint. If zero,
	// DefaultErrorThreshold is used.
	ErrorThreshold int

	// MinTestInterval is the minimum interval to keep between two opportunistic
	// tests. Opportunistic tests are scheduled only when a DNS request attempt
	// is performed and the last test happened at list TestMinInterval age.
	MinTestInterval time.Duration

	// GetMinTestInterval returns the MinTestInterval to use for e. If
	// GetMinTestInterval returns 0 or is unset, MinTestInterval is used.
	GetMinTestInterval func(e Endpoint) time.Duration

	// TestEndpoint specifies a custom tester for e. If not defined or nil
	// returned, Test is called on e.
	EndpointTester func(e Endpoint) Tester

	// OnChange is called whenever the active endpoint changes.
	OnChange func(e Endpoint)

	// OnConnect is called whenever an endpoint connects (for connected
	// endpoints).
	OnConnect func(*ConnectInfo)

	// OnError is called each time a test on e failed, forcing Manager to
	// fallback to the next endpoint. If e is nil, the error happened on the
	// Provider.
	OnError func(e Endpoint, err error)

	// OnProviderError is called when a provider returns an error.
	OnProviderError func(p Provider, err error)

	// DebugLog is getting verbose logs if set.
	DebugLog func(msg string)
	// contains filtered or unexported fields
}

type Protocol int

type Provider interface {
	fmt.Stringer
	GetEndpoints(ctx context.Context) ([]Endpoint, error)
}

type ProviderFunc func(ctx context.Context) ([]Endpoint, error)

type SourceHTTPSSVCProvider struct {
	Hostname string
	Source   Endpoint
}

type SourceURLProvider struct {
	// SourceURL is a URL pointing to a JSON resource listing one or more
	// Endpoints.
	SourceURL string

	// Client is the http.Client to use to fetch SourceURL. If not defined,
	// http.DefaultClient is used.
	Client *http.Client
	// contains filtered or unexported fields
}

type StaticProvider []Endpoint

type Tester func(ctx context.Context, testDomain string) error