registry

Documentation

Overview

Package mdns is a multicast dns registry

Package registry is an interface for service discovery

Index

• Variables
• func Deregister(s *Service) error
• func Register(s *Service, opts ...RegisterOption) error
• func String() string
• type DeregisterOption
  • func DeregisterContext(ctx context.Context) DeregisterOption
• type DeregisterOptions
• type Endpoint
• type Event
• type EventType
  • func (t EventType) String() string
• type GetOption
  • func GetContext(ctx context.Context) GetOption
• type GetOptions
• type ListOption
  • func ListContext(ctx context.Context) ListOption
• type ListOptions
• type Node
• type Option
  • func Addrs(addrs ...string) Option
  • func Logger(l logger.Logger) Option
  • func Secure(b bool) Option
  • func Services(s map[string][]*Service) Option
  • func TLSConfig(t *tls.Config) Option
  • func Timeout(t time.Duration) Option
• type Options
  • func NewOptions(opts ...Option) *Options
• type RegisterOption
  • func RegisterContext(ctx context.Context) RegisterOption
  • func RegisterTTL(t time.Duration) RegisterOption
• type RegisterOptions
• type Registry
  • func NewMemoryRegistry(opts ...Option) Registry
  • func NewRegistry(opts ...Option) Registry
• type Result
• type Service
  • func GetService(name string) ([]*Service, error)
  • func ListServices() ([]*Service, error)
• type Value
• type WatchOption
  • func WatchContext(ctx context.Context) WatchOption
  • func WatchService(name string) WatchOption
• type WatchOptions
• type Watcher
  • func Watch(opts ...WatchOption) (Watcher, error)

Variables

var (
	DefaultRegistry = NewRegistry()

	// Not found error when GetService is called
	ErrNotFound = errors.New("service not found")
	// Watcher stopped error when watcher is stopped
	ErrWatcherStopped = errors.New("watcher stopped")
)

Functions

func Deregister

func Deregister(s *Service) error

Deregister a service node

func Register

func Register(s *Service, opts ...RegisterOption) error

Register a service node. Additionally supply options such as TTL.

func String

func String() string

Types

type DeregisterOption

type DeregisterOption func(*DeregisterOptions)

func DeregisterContext

func DeregisterContext(ctx context.Context) DeregisterOption

type DeregisterOptions

type DeregisterOptions struct {
	Context context.Context
}

type Endpoint

type Endpoint struct {
	Name     string            `json:"name"`
	Request  *Value            `json:"request"`
	Response *Value            `json:"response"`
	Metadata map[string]string `json:"metadata"`
}

type Event

type Event struct {
	// Id is registry id
	Id string
	// Type defines type of event
	Type EventType
	// Timestamp is event timestamp
	Timestamp time.Time
	// Service is registry service
	Service *Service
}

Event is registry event

type EventType

type EventType int

EventType defines registry event type

const (
	// Create is emitted when a new service is registered
	Create EventType = iota
	// Delete is emitted when an existing service is deregsitered
	Delete
	// Update is emitted when an existing servicec is updated
	Update
)

func (EventType) String

func (t EventType) String() string

String returns human readable event type

type GetOption

type GetOption func(*GetOptions)

func GetContext

func GetContext(ctx context.Context) GetOption

type GetOptions

type GetOptions struct {
	Context context.Context
}

type ListOption

type ListOption func(*ListOptions)

func ListContext

func ListContext(ctx context.Context) ListOption

type ListOptions

type ListOptions struct {
	Context context.Context
}

type Node

type Node struct {
	Id       string            `json:"id"`
	Address  string            `json:"address"`
	Metadata map[string]string `json:"metadata"`
}

type Option

type Option func(*Options)

func Addrs

func Addrs(addrs ...string) Option

Addrs is the registry addresses to use

func Logger

func Logger(l logger.Logger) Option

Logger sets the underline logger

func Secure

func Secure(b bool) Option

Secure communication with the registry

func Services

func Services(s map[string][]*Service) Option

Services is an option that preloads service data

func TLSConfig

func TLSConfig(t *tls.Config) Option

Specify TLS Config

func Timeout

func Timeout(t time.Duration) Option

type Options

type Options struct {
	Addrs     []string
	Timeout   time.Duration
	Secure    bool
	TLSConfig *tls.Config
	Logger    logger.Logger
	// Other options for implementations of the interface
	// can be stored in a context
	Context context.Context
}

func NewOptions

func NewOptions(opts ...Option) *Options

type RegisterOption

type RegisterOption func(*RegisterOptions)

func RegisterContext

func RegisterContext(ctx context.Context) RegisterOption

func RegisterTTL

func RegisterTTL(t time.Duration) RegisterOption

type RegisterOptions

type RegisterOptions struct {
	TTL time.Duration
	// Other options for implementations of the interface
	// can be stored in a context
	Context context.Context
}

type Registry

type Registry interface {
	Init(...Option) error
	Options() Options
	Register(*Service, ...RegisterOption) error
	Deregister(*Service, ...DeregisterOption) error
	GetService(string, ...GetOption) ([]*Service, error)
	ListServices(...ListOption) ([]*Service, error)
	Watch(...WatchOption) (Watcher, error)
	String() string
}

The registry provides an interface for service discovery and an abstraction over varying implementations {consul, etcd, zookeeper, ...}

func NewMemoryRegistry

func NewMemoryRegistry(opts ...Option) Registry

func NewRegistry

func NewRegistry(opts ...Option) Registry

NewRegistry returns a new default registry which is mdns

type Result

type Result struct {
	Action  string
	Service *Service
}

Result is returned by a call to Next on the watcher. Actions can be create, update, delete

type Service

type Service struct {
	Name      string            `json:"name"`
	Version   string            `json:"version"`
	Metadata  map[string]string `json:"metadata"`
	Endpoints []*Endpoint       `json:"endpoints"`
	Nodes     []*Node           `json:"nodes"`
}

func GetService

func GetService(name string) ([]*Service, error)

Retrieve a service. A slice is returned since we separate Name/Version.

func ListServices

func ListServices() ([]*Service, error)

List the services. Only returns service names

type Value

type Value struct {
	Name   string   `json:"name"`
	Type   string   `json:"type"`
	Values []*Value `json:"values"`
}

type WatchOption

type WatchOption func(*WatchOptions)

func WatchContext

func WatchContext(ctx context.Context) WatchOption

func WatchService

func WatchService(name string) WatchOption

Watch a service

type WatchOptions

type WatchOptions struct {
	// Specify a service to watch
	// If blank, the watch is for all services
	Service string
	// Other options for implementations of the interface
	// can be stored in a context
	Context context.Context
}

type Watcher

type Watcher interface {
	// Next is a blocking call
	Next() (*Result, error)
	Stop()
}

Watcher is an interface that returns updates about services within the registry.

func Watch

func Watch(opts ...WatchOption) (Watcher, error)

Watch returns a watcher which allows you to track updates to the registry.