Documentation
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Overview ¶
Package ready provides an http.Handler wrapper that gates requests on a readiness check. While ServiceStatus.IsReady reports false every request is answered with a JSON 503 "not_ready" error instead of reaching the delegate handler.
h := ready.NewServiceStatusVerifier(server, next)
restserver uses it so that a server whose services are still initialising (or that has stopped serving) reports unavailable to load balancers.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func NewServiceStatusVerifier ¶
func NewServiceStatusVerifier(s ServiceStatus, delegate http.Handler) http.Handler
NewServiceStatusVerifier returns a ServiceReadyVerifier that answers requests with a JSON 503 not_ready error (via marshal.WriteJSON) carrying the request's correlation ID while s is not ready, and chains to delegate otherwise. The error is built per request; nothing is shared.
Types ¶
type ServiceReadyVerifier ¶
type ServiceReadyVerifier struct {
// Status is the readiness probe.
Status ServiceStatus
// Delegate handles requests while Status is ready.
Delegate http.Handler
// NotReadyHandler handles requests while Status is not ready.
NotReadyHandler http.Handler
}
ServiceReadyVerifier is a http.Handler that checks if the service is ready to serve, and if so chains to Delegate, otherwise calls NotReadyHandler. All fields must be set; NewServiceStatusVerifier provides the JSON 503 default for NotReadyHandler.
func (*ServiceReadyVerifier) ServeHTTP ¶
func (c *ServiceReadyVerifier) ServeHTTP(w http.ResponseWriter, r *http.Request)
ServeHTTP implements the http.Handler interface
type ServiceStatus ¶
type ServiceStatus interface {
// IsReady reports whether requests may be served right now. It is
// called concurrently and must be cheap and safe for concurrent use.
IsReady() bool
}
ServiceStatus is the readiness probe consulted on every request. restserver.Server satisfies it.
Source Files