in

Documentation

Index

• func NormalizeForID(addr string) string
• type AdminHTTPConfig
• type FrontendHTTPConfig
• type Manager
  • func NewManager(config *ServerConfig, dialer common.BackendDialer) *Manager
  • func (mgr *Manager) AddSessionListener(sessionListener common.SessionListener)
  • func (mgr *Manager) AddValveProvider(vp common.ValveProvider)
  • func (mgr *Manager) RegisterHTTPHandlers(http *http.ServeMux)
  • func (mgr *Manager) ServeWs(w http.ResponseWriter, r *http.Request)
  • func (mgr *Manager) Start()
  • func (mgr *Manager) Stop()
• type ServerConfig

Functions

func NormalizeForID

func NormalizeForID(addr string) string

NormalizeForID builds a normalized ID from given url or listen address so that it can be used in the system as unique identifier for various IDs. The returned value will not have any special character apart from alphabets and numbers. All other characters will be replaced with hyphen (-) in the result.

Types

type AdminHTTPConfig

type AdminHTTPConfig struct {
	Addr           string        `yaml:"address" env:"ADM_ADDR" env-description:"Admin server listen address" env-default:":8081"`
	ReadTimeout    time.Duration `yaml:"read-timeout" env:"ADM_READ_TIMEOUT" env-description:"Admin server read timeout" env-default:"10s"`
	WriteTimeout   time.Duration `yaml:"wite-timeout" env:"ADM_WRITE_TIMEOUT" env-description:"Admin server write timeout" env-default:"10s"`
	MaxHeaderBytes int           `yaml:"max-header-bytes" env:"ADM_MAX_HDR_BYTES" env-description:"Admin server Max Header Size" env-default:"524288"`
}

AdminHTTPConfig is the HTTP server config for receiving admin API requests. This endpoint MUST NOT be exposed to outside world. As of now, the admin interface DO NOT have any security in place and it is designed to be used within a trusted environment. Future version of balancer may add security controls to admin interface.

type FrontendHTTPConfig

type FrontendHTTPConfig struct {
	Addr           string        `yaml:"address" env:"FE_ADDR" env-description:"Frontend server listen address" env-default:":8080"`
	ReadTimeout    time.Duration `yaml:"read-timeout" env:"FE_READ_TIMEOUT" env-description:"Frontend server read timeout" env-default:"10s"`
	WriteTimeout   time.Duration `yaml:"wite-timeout" env:"FE_WRITE_TIMEOUT" env-description:"Frontend server write timeout" env-default:"10s"`
	MaxHeaderBytes int           `yaml:"max-header-bytes" env:"FE_MAX_HDR_BYTES" env-description:"Frontend server Max Header Size" env-default:"524288"`
}

FrontendHTTPConfig is the HTTP server config for incoming websocket requests. This endpoint must be exposed to outside world using appropriate means (via another reverse-proxy or firewall or cloud balancer etc)

type Manager

type Manager struct {
	// contains filtered or unexported fields
}

Manager is a pool of incoming frontend client connections along with mapped outgoing backend connections. It's responsible for housekeeping of all proxy sessions in the system.

func NewManager

func NewManager(config *ServerConfig, dialer common.BackendDialer) *Manager

NewManager creates a new initialized Manager with given configuration and given backend dialer. The manager is only initialized and it's registration and de-registration loops are NOT started automatically yet. The caller MUST call Start() method on the newly created Manager instance before using the Manager for any balancer purposes.

func (*Manager) AddSessionListener

func (mgr *Manager) AddSessionListener(sessionListener common.SessionListener)

AddSessionListener adds a new SessionListener to list of existing sessionsListeners of this manager.

func (*Manager) AddValveProvider

func (mgr *Manager) AddValveProvider(vp common.ValveProvider)

AddValveProvider adds new ValveProvider at end of the chain. Each session will receive it's valves by calling AddValves method of all of the available ValveProviders with the Manager.

func (*Manager) RegisterHTTPHandlers

func (mgr *Manager) RegisterHTTPHandlers(http *http.ServeMux)

RegisterHTTPHandlers registers actionable endpoints to supplied mux

func (*Manager) ServeWs

func (mgr *Manager) ServeWs(w http.ResponseWriter, r *http.Request)

ServeWs is the main handler function for incoming websocket requests. This can be used in any

func (*Manager) Start

func (mgr *Manager) Start()

Start the registration and de-registration loop in separate goroutine

func (*Manager) Stop

func (mgr *Manager) Stop()

Stop the Manager and associated sessions by (a) closing all active sessions and (b) terminating the registration and de-registration routine

type ServerConfig

type ServerConfig struct {
	FrontendHTTP          FrontendHTTPConfig `yaml:"frontend"`
	AdminHTTP             AdminHTTPConfig    `yaml:"admin"`
	ReadBufferSize        int                `yaml:"read-buffer-size" env:"FE_RB_SIZE" env-description:"WebSocket ReadBuffer size (bytes)" env-default:"1024"`
	WriteBufferSize       int                `yaml:"write-buffer-size" env:"FE_WB_SIZE" env-description:"WebSocket WriteBuffer size (bytes)" env-default:"1024"`
	TrustReceivedXff      bool               `yaml:"trust-received-xff" env:"FE_TRUST_XFF" env-description:"Trust X-Forwarded-For header from clients" env-default:"true"`
	IgnoreHeaders         []string           `yaml:"block-headers" env:"BLOCK_HEADERS" env-description:"Additional headers to block, comma separated"`
	ReconnectHeader       string             `` /* 131-byte string literal not displayed */
	EnableInstrumentation bool               `yaml:"enable-instrumentation" env:"ENABLE_INST" env-description:"Enable Prometheus instrumentation" env-default:"false"`
	LoggingLevel          string             `yaml:"logging-level" env:"LOG_LEVEL" env-description:"Logging level" env-default:"WARN"`
}

ServerConfig combines Frontend and Admin http servers configuration and other parameters needed by frontend system to operate properly. The configuration is supported via yml configuration file or via environment variables. Another option, especially useful for those integrating balancer into their own program, is to build up this configuration by any means they need to and use this configuration to bootstrap balancer.

All the parameters having env tags can be set by passing these parameters as environment variables while launching the balancer. If set, environment variables takes precedence over values from yml. All parameters having env-default in their tag will assume these values if not present either in yml file OR in environment variable.

Environment variables are evaluated and considered ONLY if yml configuration file is being used for configuration. Environment variables will have NO effect if you are programatically building configuration yourself instead of parsing a yml config file.