storage

Documentation

Index

• Constants
• Variables
• func Error(msg string) func(string) StoreErr
• func IsNotFoundErr(err StoreErr) bool
• func NewKeyForConfig(id string) string
• func NewKeyForEvent(id string, cfgName string) string
• func NewKeyForMachine(id string, cfgName string) string
• func NewKeyForMachinesByState(cfgName, state string) string
• func NewKeyForOutcome(id string, cfgName string) string
• type ConfigStore
• type EventStore
• type FSMStore
• type RedisStore
  • func (csm *RedisStore) AddEventOutcome(id string, cfg string, response *protos.EventOutcome, ttl time.Duration) StoreErr
  • func (csm *RedisStore) GetAllConfigs() []string
  • func (csm *RedisStore) GetAllInState(cfg string, state string) []string
  • func (csm *RedisStore) GetAllVersions(name string) []string
  • func (csm *RedisStore) GetConfig(id string) (*protos.Configuration, StoreErr)
  • func (csm *RedisStore) GetEvent(id string, cfg string) (*protos.Event, StoreErr)
  • func (csm *RedisStore) GetOutcomeForEvent(id string, cfg string) (*protos.EventOutcome, StoreErr)
  • func (csm *RedisStore) GetStateMachine(id string, cfg string) (*protos.FiniteStateMachine, StoreErr)
  • func (csm *RedisStore) GetTimeout() time.Duration
  • func (csm *RedisStore) Health() StoreErr
  • func (csm *RedisStore) PutConfig(cfg *protos.Configuration) StoreErr
  • func (csm *RedisStore) PutEvent(event *protos.Event, cfg string, ttl time.Duration) StoreErr
  • func (csm *RedisStore) PutStateMachine(id string, stateMachine *protos.FiniteStateMachine) StoreErr
  • func (csm *RedisStore) SetLogLevel(level slf4go.LogLevel)
  • func (csm *RedisStore) SetTimeout(duration time.Duration)
  • func (csm *RedisStore) TxProcessEvent(id, cfgName string, evt *protos.Event) StoreErr
  • func (csm *RedisStore) UpdateState(cfgName string, id string, oldState string, newState string) StoreErr
• type StoreErr
• type StoreManager
  • func NewRedisStore(address string, isCluster bool, db int, timeout time.Duration, maxRetries int) StoreManager
  • func NewRedisStoreWithDefaults(address string) StoreManager

Constants

const (
	ConfigsPrefix = "configs"
	EventsPrefix  = "events"
	FsmPrefix     = "fsm"

	KeyPrefixComponentsSeparator = ":"
	KeyPrefixIDSeparator         = "#"
)

const (
	NeverExpire         = 0
	DefaultRedisDb      = 0
	DefaultMaxRetries   = 3
	DefaultTimeout      = 200 * time.Millisecond
	ReturningItemsFmt   = "Returning %d items"
	NoConfigurationsFmt = "Could not retrieve configurations: %s"
)

Variables

var (
	AlreadyExistsError  = Error("key %s already exists")
	GenericStoreError   = Error("store error: %v")
	InvalidDataError    = Error("error storing invalid data: %v")
	NotFoundError       = Error("key %s not found")
	NotImplementedError = Error("functionality %s has not been implemented yet")
	TooManyAttempts     = Error("retries exceeded")
)

Functions

func Error

func Error(msg string) func(string) StoreErr

func IsNotFoundErr

func IsNotFoundErr(err StoreErr) bool

func NewKeyForConfig

func NewKeyForConfig(id string) string

NewKeyForConfig configs#<config:id>

By convention, the config ID is the `name:version` of the configuration; however, this is not enforced here, but rather in the implementation of the stores.

func NewKeyForEvent

func NewKeyForEvent(id string, cfgName string) string

NewKeyForEvent events:<cfg:name>#<event:id>

func NewKeyForMachine

func NewKeyForMachine(id string, cfgName string) string

NewKeyForMachine fsm:<cfg:name>#<machine:id>

func NewKeyForMachinesByState

func NewKeyForMachinesByState(cfgName, state string) string

NewKeyForMachinesByState fsm:<cfg:name>:state#<state>

func NewKeyForOutcome

func NewKeyForOutcome(id string, cfgName string) string

NewKeyForOutcome events:<cfg:name>:outcome#<event:id>

Types

type ConfigStore

type ConfigStore interface {
	GetConfig(versionId string) (*protos.Configuration, StoreErr)
	PutConfig(cfg *protos.Configuration) StoreErr

	// GetAllConfigs returns all the `Configurations` that exist in the store, regardless of
	// the version, and whether they are used or not by an FSM.
	GetAllConfigs() []string

	// GetAllVersions returns the full `name:version` ID of all the Configurations whose
	// name matches `name`.
	GetAllVersions(name string) []string
}

type EventStore

type EventStore interface {
	GetEvent(id string, cfg string) (*protos.Event, StoreErr)
	PutEvent(event *protos.Event, cfg string, ttl time.Duration) StoreErr

	// AddEventOutcome adds the outcome of an event to the storage, given the `eventId` and the
	// "type" (`Configuration.Name`) of the FSM that received the event.
	//
	// Optionally, it will remove the outcome after a given `ttl` (time-to-live); use
	// `NeverExpire` to keep the outcome forever.
	AddEventOutcome(eventId string, cfgName string, response *protos.EventOutcome,
		ttl time.Duration) StoreErr

	// GetOutcomeForEvent returns the outcome of an event, given the `eventId` and the "type" of the
	// FSM that received the event.
	GetOutcomeForEvent(eventId string, cfgName string) (*protos.EventOutcome, StoreErr)
}

type FSMStore

type FSMStore interface {
	// GetStateMachine will find the FSM with `id and that is configured via a `Configuration` whose
	// `name` matches `cfg` (without the `version`).
	GetStateMachine(id string, cfg string) (*protos.FiniteStateMachine, StoreErr)

	// PutStateMachine creates or updates the FSM whose `id` is given.
	// No further action is taken: no check that the referenced `Configuration` exists, and the
	// `state` SETs are not updated either: it is the caller's responsibility to call the
	// `UpdateState` method (possibly with an empty `oldState`, in the case of creation).
	PutStateMachine(id string, fsm *protos.FiniteStateMachine) StoreErr

	// GetAllInState looks up all the FSMs that are currently in the given `state` and
	// are configured with a `Configuration` whose name matches `cfg` (regardless of the
	// configuration's version).
	//
	// It returns the IDs for the FSMs.
	GetAllInState(cfg string, state string) []string

	// UpdateState will move the FSM's `id` from/to the respective Redis SETs.
	//
	// When creating or updating an FSM with `PutStateMachine`, the state SETs are not
	// modified; it is the responsibility of the caller to manage the FSM state appropriately
	// (or not, as the case may be).
	//
	// `oldState` may be empty in the case of a new FSM being created.
	UpdateState(cfgName string, id string, oldState string, newState string) StoreErr

	// TxProcessEvent processes an Event for the FSM in a transaction, guaranteeing that
	// there will be no races when updating the FSM state.
	TxProcessEvent(id, cfgName string, evt *protos.Event) StoreErr
}

type RedisStore

type RedisStore struct {
	Timeout    time.Duration
	MaxRetries int
	// contains filtered or unexported fields
}

func (*RedisStore) AddEventOutcome

func (csm *RedisStore) AddEventOutcome(id string, cfg string, response *protos.EventOutcome, ttl time.Duration) StoreErr

func (*RedisStore) GetAllConfigs

func (csm *RedisStore) GetAllConfigs() []string

func (*RedisStore) GetAllInState

func (csm *RedisStore) GetAllInState(cfg string, state string) []string

func (*RedisStore) GetAllVersions

func (csm *RedisStore) GetAllVersions(name string) []string

func (*RedisStore) GetConfig

func (csm *RedisStore) GetConfig(id string) (*protos.Configuration, StoreErr)

func (*RedisStore) GetEvent

func (csm *RedisStore) GetEvent(id string, cfg string) (*protos.Event, StoreErr)

func (*RedisStore) GetOutcomeForEvent

func (csm *RedisStore) GetOutcomeForEvent(id string, cfg string) (*protos.EventOutcome, StoreErr)

func (*RedisStore) GetStateMachine

func (csm *RedisStore) GetStateMachine(id string, cfg string) (*protos.FiniteStateMachine, StoreErr)

func (*RedisStore) GetTimeout

func (csm *RedisStore) GetTimeout() time.Duration

func (*RedisStore) Health

func (csm *RedisStore) Health() StoreErr

Health checks that the cmd is ready to accept connections

func (*RedisStore) PutConfig

func (csm *RedisStore) PutConfig(cfg *protos.Configuration) StoreErr

func (*RedisStore) PutEvent

func (csm *RedisStore) PutEvent(event *protos.Event, cfg string, ttl time.Duration) StoreErr

func (*RedisStore) PutStateMachine

func (csm *RedisStore) PutStateMachine(id string, stateMachine *protos.FiniteStateMachine) StoreErr

func (*RedisStore) SetLogLevel

func (csm *RedisStore) SetLogLevel(level slf4go.LogLevel)

SetLogLevel for RedisStore implements the Loggable interface

func (*RedisStore) SetTimeout

func (csm *RedisStore) SetTimeout(duration time.Duration)

func (*RedisStore) TxProcessEvent

func (csm *RedisStore) TxProcessEvent(id, cfgName string, evt *protos.Event) StoreErr

func (*RedisStore) UpdateState

func (csm *RedisStore) UpdateState(cfgName string, id string, oldState string, newState string) StoreErr

type StoreErr

type StoreErr = error

type StoreManager

type StoreManager interface {
	log.Loggable
	ConfigStore
	FSMStore
	EventStore
	SetTimeout(duration time.Duration)
	GetTimeout() time.Duration
	Health() error
}

func NewRedisStore

func NewRedisStore(address string, isCluster bool, db int, timeout time.Duration, maxRetries int) StoreManager

NewRedisStore creates a new StoreManager backed by a Redis cmd, reachable at address, in cluster configuration if isCluster is set to true. The db value indicates which database to use.

Some store queries (typically the get and put actions) will be retried up to maxRetries times, if they time out after timeout expires. Use the [Health] function to check whether the store is reachable.

func NewRedisStoreWithDefaults

func NewRedisStoreWithDefaults(address string) StoreManager

NewRedisStoreWithDefaults creates a new StoreManager backed by a Redis cmd, with all default settings, in a single node configuration.