configwait

Documentation

Overview

Package configwait provides utilities for waiting on configuration availability during startup.

Index

• Constants
• func Wait(ctx context.Context, cfg Config, load LoadFunc) error
• type Config
  • func NewConfigFromEnv() Config
• type LoadFunc
• type ReadyGate
  • func NewReadyGate(inner http.Handler, allowedPaths []string) *ReadyGate
  • func (rg *ReadyGate) IsReady() bool
  • func (rg *ReadyGate) ServeHTTP(w http.ResponseWriter, r *http.Request)
  • func (rg *ReadyGate) SetHandler(h http.Handler)
  • func (rg *ReadyGate) SetReady()
• type ReloadFunc
• type Reloader
  • func NewReloader(ctx context.Context, gate *ReadyGate, reloadFunc ReloadFunc) *Reloader
  • func (r *Reloader) Start() <-chan struct{}
  • func (r *Reloader) Trigger()

Constants

const (
	EnvMaxRetries    = "CONFIG_WAIT_MAX_RETRIES"
	EnvRetryInterval = "CONFIG_WAIT_RETRY_INTERVAL"
)

const (
	DefaultMaxRetries    = 30
	DefaultRetryInterval = 2 * time.Second
)

Functions

func Wait

func Wait(ctx context.Context, cfg Config, load LoadFunc) error

Wait blocks until load succeeds or max retries is reached.

Types

type Config

type Config struct {
	MaxRetries    int
	RetryInterval time.Duration
}

Config configures the wait behavior.

func NewConfigFromEnv

func NewConfigFromEnv() Config

NewConfigFromEnv creates a Config from environment variables.

type LoadFunc

type LoadFunc func(ctx context.Context) error

LoadFunc attempts to load configuration; returns nil on success.

type ReadyGate

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

ReadyGate gates HTTP requests until the service is ready.

func NewReadyGate

func NewReadyGate(inner http.Handler, allowedPaths []string) *ReadyGate

NewReadyGate creates a ReadyGate wrapping the given handler. The allowedPaths are path prefixes always allowed through (e.g., "/setup"). The inner handler can be nil initially; call SetHandler() once ready.

func (*ReadyGate) IsReady

func (rg *ReadyGate) IsReady() bool

IsReady returns true if the service is ready.

func (*ReadyGate) ServeHTTP

func (rg *ReadyGate) ServeHTTP(w http.ResponseWriter, r *http.Request)

ServeHTTP implements http.Handler.

func (*ReadyGate) SetHandler

func (rg *ReadyGate) SetHandler(h http.Handler)

SetHandler sets the main handler to use once ready.

func (*ReadyGate) SetReady

func (rg *ReadyGate) SetReady()

SetReady marks the service as ready to handle all requests.

type ReloadFunc

type ReloadFunc func(ctx context.Context) error

ReloadFunc is called when a reload is triggered.

type Reloader

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

Reloader manages configuration reloading via SIGHUP or programmatic triggers.

func NewReloader

func NewReloader(ctx context.Context, gate *ReadyGate, reloadFunc ReloadFunc) *Reloader

NewReloader creates a Reloader that calls reloadFunc when triggered.

func (*Reloader) Start

func (r *Reloader) Start() <-chan struct{}

Start begins listening for SIGHUP signals and programmatic triggers. Returns a channel that closes when the reloader stops.

func (*Reloader) Trigger

func (r *Reloader) Trigger()

Trigger requests a configuration reload. Safe to call from any goroutine.