open-vault/serviceregistration/service_registration.go

97 lines
3.8 KiB
Go

package serviceregistration
/*
ServiceRegistration is an interface that can be fulfilled to use
varying applications for service discovery, regardless of the physical
back-end used.
Service registration implements notifications for changes in _dynamic_
properties regarding Vault's health. Vault's version is the only static
property given in state for now, but if there's a need for more in the future,
we could add them on.
*/
import (
"sync"
log "github.com/hashicorp/go-hclog"
)
type State struct {
VaultVersion string
IsInitialized, IsSealed, IsActive, IsPerformanceStandby bool
}
// Factory is the factory function to create a ServiceRegistration.
// The config is the key/value pairs set _inside_ the service registration config stanza.
// The state is the initial state.
// The redirectAddr is Vault core's RedirectAddr.
type Factory func(config map[string]string, logger log.Logger, state State) (ServiceRegistration, error)
// ServiceRegistration is an interface that advertises the state of Vault to a
// service discovery network.
type ServiceRegistration interface {
// Run provides a shutdownCh, wait WaitGroup, and redirectAddr. The
// shutdownCh is for monitoring when a shutdown occurs and initiating any
// actions needed to leave service registration in a final state. When
// finished, signalling that with wait means that Vault will wait until
// complete. The redirectAddr is an optional parameter for implementations
// that might need to communicate with Vault's listener via this address.
//
// Run is called just after Factory instantiation so can be relied upon
// for controlling shutdown behavior.
// Here is an example of its intended use:
// func Run(shutdownCh <-chan struct{}, wait sync.WaitGroup, redirectAddr string) error {
//
// // Since we are going to want Vault to wait to shutdown
// // until after we do cleanup...
// wait.Add(1)
//
// // Run shutdown code in a goroutine so Run doesn't block.
// go func(){
// // Ensure that when this ends, no matter how it ends,
// // we don't cause Vault to hang on shutdown.
// defer wait.Done()
//
// // Now wait until we're actually receiving a shutdown.
// <-shutdownCh
//
// // Now do whatever we need to clean up.
// if err := someService.SetFinalState(); err != nil {
// // Log it at error level.
// }
// }()
// return nil
// }
Run(shutdownCh <-chan struct{}, wait *sync.WaitGroup, redirectAddr string) error
// NotifyActiveStateChange is used by Core to notify that this Vault
// instance has changed its status on whether it's active or is
// a standby.
// If errors are returned, Vault only logs a warning, so it is
// the implementation's responsibility to retry updating state
// in the face of errors.
NotifyActiveStateChange(isActive bool) error
// NotifySealedStateChange is used by Core to notify that Vault has changed
// its Sealed status to sealed or unsealed.
// If errors are returned, Vault only logs a warning, so it is
// the implementation's responsibility to retry updating state
// in the face of errors.
NotifySealedStateChange(isSealed bool) error
// NotifyPerformanceStandbyStateChange is used by Core to notify that this
// Vault instance has changed its performance standby status.
// If errors are returned, Vault only logs a warning, so it is
// the implementation's responsibility to retry updating state
// in the face of errors.
NotifyPerformanceStandbyStateChange(isStandby bool) error
// NotifyInitializedStateChange is used by Core to notify that the core is
// initialized.
// If errors are returned, Vault only logs a warning, so it is
// the implementation's responsibility to retry updating state
// in the face of errors.
NotifyInitializedStateChange(isInitialized bool) error
}