Documentation ¶
Overview ¶
Package actor declares the types used to represent actors in the Actor Model.
The actors model provide a high level abstraction for writing concurrent and distributed systems. This approach simplifies the burden imposed on engineers, such as explicit locks and concurrent access to shared state, as actors receive messages synchronously.
The following quote from Wikipedia distills the definition of an actor down to its essence
In response to a message that it receives, an actor can: make local decisions, create more actors, send more messages, and determine how to respond to the next message received.
Creating Actors ¶
Props provide the building blocks for declaring how actors should be created. The following example defines an actor using a function literal to process messages:
var props Props = actor.PropsFromFunc(func(c Context) { // process messages })
Alternatively, a type which conforms to the Actor interface, by defining a single Receive method, can be used.
type MyActor struct {} func (a *MyActor) Receive(c Context) { // process messages } var props Props = actor.PropsFromProducer(func() Actor { return &MyActor{} })
Spawn and SpawnNamed use the given props to create a running instances of an actor. Once spawned, the actor is ready to process incoming messages. To spawn an actor with a unique name, use
pid := context.Spawn(props)
The result of calling Spawn is a unique PID or process identifier.
Each time an actor is spawned, a new mailbox is created and associated with the PID. Messages are sent to the mailbox and then forwarded to the actor to process.
Processing Messages ¶
An actor processes messages via its Receive handler. The signature of this function is:
Receive(c actor.Context)
The actor system guarantees that this method is called synchronously, therefore there is no requirement to protect shared state inside calls to this function.
Communicating With Actors ¶
A PID is the primary interface for sending messages to actors. The PID.Tell method is used to send an asynchronous message to the actor associated with the PID:
pid.Tell("Hello World")
Depending on the requirements, communication between actors can take place synchronously or asynchronously. Regardless of the circumstances, actors always communicate via a PID.
When sending a message using PID.Request or PID.RequestFuture, the actor which receives the message will respond using the Context.Sender method, which returns the PID of of the sender.
For synchronous communication, an actor will use a Future and wait for the result before continuing. To send a message to an actor and wait for a response, use the RequestFuture method, which returns a Future:
f := actor.RequestFuture(pid,"Hello", 50 * time.Millisecond) res, err := f.Result() // waits for pid to reply
Example ¶
Demonstrates how to create an actor using a function literal and how to send a message asynchronously
package main import ( "fmt" "time" "github.com/ChaokunChang/protoactor-go/actor" ) func main() { var context = actor.EmptyRootContext var props = actor.PropsFromFunc(func(c actor.Context) { if msg, ok := c.Message().(string); ok { fmt.Println(msg) // outputs "Hello World" } }) pid := context.Spawn(props) context.Send(pid, "Hello World") time.Sleep(time.Millisecond * 100) context.StopFuture(pid).Wait() // wait for the actor to stop }
Output: Hello World
Example (Synchronous) ¶
Demonstrates how to send a message from one actor to another and for the caller to wait for a response before proceeding
package main import ( "fmt" "sync" "github.com/ChaokunChang/protoactor-go/actor" ) func main() { var wg sync.WaitGroup wg.Add(1) // callee will wait for the PING message callee := actor.EmptyRootContext.Spawn(actor.PropsFromFunc(func(c actor.Context) { if msg, ok := c.Message().(string); ok { fmt.Println(msg) // outputs PING c.Respond("PONG") } })) // caller will send a PING message and wait for the PONG caller := actor.EmptyRootContext.Spawn(actor.PropsFromFunc(func(c actor.Context) { switch msg := c.Message().(type) { // the first message an actor receives after it has started case *actor.Started: // send a PING to the callee, and specify the response // is sent to Self, which is this actor's PID c.Request(callee, "PING") case string: fmt.Println(msg) // PONG wg.Done() } })) wg.Wait() actor.EmptyRootContext.StopFuture(callee).Wait() actor.EmptyRootContext.StopFuture(caller).Wait() }
Output: PING PONG
Index ¶
- Variables
- func SetLogLevel(level log.Level)
- func SetOptions(opts ...optionFn)
- func UnwrapEnvelope(message interface{}) (ReadonlyMessageHeader, interface{}, *PID)
- func UnwrapEnvelopeMessage(message interface{}) interface{}
- func WithDeadLetterSubscriber(fn func(evt interface{})) optionFn
- func WithSupervisorSubscriber(fn func(evt interface{})) optionFn
- type Actor
- type ActorFunc
- type ActorProcess
- type AddressResolver
- type AutoReceiveMessage
- type Behavior
- type Context
- type ContextDecorator
- type ContextDecoratorFunc
- type DeadLetterEvent
- type DeciderFunc
- type Directive
- type Failure
- type Future
- type InboundMiddlewaredeprecated
- type MessageEnvelope
- type NotInfluenceReceiveTimeout
- type OutboundMiddlewaredeprecated
- type PID
- func (*PID) Descriptor() ([]byte, []int)
- func (this *PID) Equal(that interface{}) bool
- func (m *PID) GetAddress() string
- func (m *PID) GetId() string
- func (pid *PID) GracefulPoison()deprecated
- func (pid *PID) GracefulStop()deprecated
- func (m *PID) Marshal() (dAtA []byte, err error)
- func (m *PID) MarshalTo(dAtA []byte) (int, error)
- func (m *PID) MarshalToSizedBuffer(dAtA []byte) (int, error)
- func (pid *PID) Poison()deprecated
- func (pid *PID) PoisonFuture() *Futuredeprecated
- func (*PID) ProtoMessage()
- func (pid *PID) Request(message interface{}, respondTo *PID)deprecated
- func (pid *PID) RequestFuture(message interface{}, timeout time.Duration) *Futuredeprecated
- func (m *PID) Reset()
- func (m *PID) Size() (n int)
- func (pid *PID) Stop()deprecated
- func (pid *PID) StopFuture() *Futuredeprecated
- func (pid *PID) String() string
- func (pid *PID) Tell(message interface{})deprecated
- func (m *PID) Unmarshal(dAtA []byte) error
- func (m *PID) XXX_DiscardUnknown()
- func (m *PID) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
- func (m *PID) XXX_Merge(src proto.Message)
- func (m *PID) XXX_Size() int
- func (m *PID) XXX_Unmarshal(b []byte) error
- type PIDSet
- func (p *PIDSet) Add(v *PID)
- func (p *PIDSet) Clear()
- func (p *PIDSet) Clone() *PIDSet
- func (p *PIDSet) Contains(v *PID) bool
- func (p *PIDSet) Empty() bool
- func (p *PIDSet) ForEach(f func(i int, pid PID))
- func (p *PIDSet) Len() int
- func (p *PIDSet) Remove(v *PID) bool
- func (p *PIDSet) Values() []PID
- type PoisonPill
- func (*PoisonPill) AutoReceiveMessage()
- func (*PoisonPill) Descriptor() ([]byte, []int)
- func (this *PoisonPill) Equal(that interface{}) bool
- func (m *PoisonPill) Marshal() (dAtA []byte, err error)
- func (m *PoisonPill) MarshalTo(dAtA []byte) (int, error)
- func (m *PoisonPill) MarshalToSizedBuffer(dAtA []byte) (int, error)
- func (*PoisonPill) ProtoMessage()
- func (m *PoisonPill) Reset()
- func (m *PoisonPill) Size() (n int)
- func (this *PoisonPill) String() string
- func (m *PoisonPill) Unmarshal(dAtA []byte) error
- func (m *PoisonPill) XXX_DiscardUnknown()
- func (m *PoisonPill) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
- func (m *PoisonPill) XXX_Merge(src proto.Message)
- func (m *PoisonPill) XXX_Size() int
- func (m *PoisonPill) XXX_Unmarshal(b []byte) error
- type Process
- type ProcessRegistryValue
- func (pr *ProcessRegistryValue) Add(process Process, id string) (*PID, bool)
- func (pr *ProcessRegistryValue) Get(pid *PID) (Process, bool)
- func (pr *ProcessRegistryValue) GetLocal(id string) (Process, bool)
- func (pr *ProcessRegistryValue) NextId() string
- func (pr *ProcessRegistryValue) RegisterAddressResolver(handler AddressResolver)
- func (pr *ProcessRegistryValue) Remove(pid *PID)
- type Producer
- type Props
- func (props *Props) WithContextDecorator(contextDecorator ...ContextDecorator) *Props
- func (props *Props) WithDispatcher(dispatcher mailbox.Dispatcher) *Props
- func (props *Props) WithFunc(f ActorFunc) *Props
- func (props *Props) WithGuardian(guardian SupervisorStrategy) *Props
- func (props *Props) WithMailbox(mailbox mailbox.Producer) *Props
- func (props *Props) WithMiddleware(middleware ...InboundMiddleware) *Propsdeprecated
- func (props *Props) WithOutboundMiddleware(middleware ...OutboundMiddleware) *Propsdeprecated
- func (props *Props) WithProducer(p Producer) *Props
- func (props *Props) WithReceiverMiddleware(middleware ...ReceiverMiddleware) *Props
- func (props *Props) WithSenderMiddleware(middleware ...SenderMiddleware) *Props
- func (props *Props) WithSpawnFunc(spawn SpawnFunc) *Props
- func (props *Props) WithSpawnMiddleware(middleware ...SpawnMiddleware) *Props
- func (props *Props) WithSupervisor(supervisor SupervisorStrategy) *Props
- type ReadonlyMessageHeader
- type ReceiveTimeout
- type ReceiverContext
- type ReceiverFunc
- type ReceiverMiddleware
- type Restart
- type RestartStatistics
- type Restarting
- type RootContext
- func (rc *RootContext) Actor() Actor
- func (rc RootContext) Copy() *RootContext
- func (rc *RootContext) Message() interface{}
- func (rc *RootContext) MessageHeader() ReadonlyMessageHeader
- func (rc *RootContext) Parent() *PID
- func (rc *RootContext) Poison(pid *PID)
- func (rc *RootContext) PoisonFuture(pid *PID) *Future
- func (rc *RootContext) Request(pid *PID, message interface{})
- func (rc *RootContext) RequestFuture(pid *PID, message interface{}, timeout time.Duration) *Future
- func (rc *RootContext) RequestWithCustomSender(pid *PID, message interface{}, sender *PID)
- func (rc *RootContext) Self() *PID
- func (rc *RootContext) Send(pid *PID, message interface{})
- func (rc *RootContext) Sender() *PID
- func (rc *RootContext) Spawn(props *Props) *PID
- func (rc *RootContext) SpawnNamed(props *Props, name string) (*PID, error)
- func (rc *RootContext) SpawnPrefix(props *Props, prefix string) *PID
- func (rc *RootContext) Stop(pid *PID)
- func (rc *RootContext) StopFuture(pid *PID) *Future
- func (rc *RootContext) WithGuardian(guardian SupervisorStrategy) *RootContext
- func (rc *RootContext) WithHeaders(headers map[string]string) *RootContext
- func (rc *RootContext) WithSenderMiddleware(middleware ...SenderMiddleware) *RootContext
- func (rc *RootContext) WithSpawnMiddleware(middleware ...SpawnMiddleware) *RootContext
- type SenderContext
- type SenderFunc
- type SenderMiddleware
- type SpawnFunc
- type SpawnMiddleware
- type SpawnerContext
- type Started
- type Stop
- func (*Stop) Descriptor() ([]byte, []int)
- func (this *Stop) Equal(that interface{}) bool
- func (m *Stop) Marshal() (dAtA []byte, err error)
- func (m *Stop) MarshalTo(dAtA []byte) (int, error)
- func (m *Stop) MarshalToSizedBuffer(dAtA []byte) (int, error)
- func (*Stop) ProtoMessage()
- func (m *Stop) Reset()
- func (m *Stop) Size() (n int)
- func (this *Stop) String() string
- func (*Stop) SystemMessage()
- func (m *Stop) Unmarshal(dAtA []byte) error
- func (m *Stop) XXX_DiscardUnknown()
- func (m *Stop) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
- func (m *Stop) XXX_Merge(src proto.Message)
- func (m *Stop) XXX_Size() int
- func (m *Stop) XXX_Unmarshal(b []byte) error
- type Stopped
- type Stopping
- type Supervisor
- type SupervisorEvent
- type SupervisorStrategy
- func DefaultSupervisorStrategy() SupervisorStrategy
- func NewAllForOneStrategy(maxNrOfRetries int, withinDuration time.Duration, decider DeciderFunc) SupervisorStrategy
- func NewExponentialBackoffStrategy(backoffWindow time.Duration, initialBackoff time.Duration) SupervisorStrategy
- func NewOneForOneStrategy(maxNrOfRetries int, withinDuration time.Duration, decider DeciderFunc) SupervisorStrategy
- func NewRestartingStrategy() SupervisorStrategy
- func RestartingSupervisorStrategy() SupervisorStrategy
- type SystemMessage
- type Terminated
- func (*Terminated) Descriptor() ([]byte, []int)
- func (this *Terminated) Equal(that interface{}) bool
- func (m *Terminated) GetAddressTerminated() bool
- func (m *Terminated) GetWho() *PID
- func (m *Terminated) Marshal() (dAtA []byte, err error)
- func (m *Terminated) MarshalTo(dAtA []byte) (int, error)
- func (m *Terminated) MarshalToSizedBuffer(dAtA []byte) (int, error)
- func (*Terminated) ProtoMessage()
- func (m *Terminated) Reset()
- func (m *Terminated) Size() (n int)
- func (this *Terminated) String() string
- func (*Terminated) SystemMessage()
- func (m *Terminated) Unmarshal(dAtA []byte) error
- func (m *Terminated) XXX_DiscardUnknown()
- func (m *Terminated) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
- func (m *Terminated) XXX_Merge(src proto.Message)
- func (m *Terminated) XXX_Size() int
- func (m *Terminated) XXX_Unmarshal(b []byte) error
- type Unwatch
- func (*Unwatch) Descriptor() ([]byte, []int)
- func (this *Unwatch) Equal(that interface{}) bool
- func (m *Unwatch) GetWatcher() *PID
- func (m *Unwatch) Marshal() (dAtA []byte, err error)
- func (m *Unwatch) MarshalTo(dAtA []byte) (int, error)
- func (m *Unwatch) MarshalToSizedBuffer(dAtA []byte) (int, error)
- func (*Unwatch) ProtoMessage()
- func (m *Unwatch) Reset()
- func (m *Unwatch) Size() (n int)
- func (this *Unwatch) String() string
- func (*Unwatch) SystemMessage()
- func (m *Unwatch) Unmarshal(dAtA []byte) error
- func (m *Unwatch) XXX_DiscardUnknown()
- func (m *Unwatch) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
- func (m *Unwatch) XXX_Merge(src proto.Message)
- func (m *Unwatch) XXX_Size() int
- func (m *Unwatch) XXX_Unmarshal(b []byte) error
- type Watch
- func (*Watch) Descriptor() ([]byte, []int)
- func (this *Watch) Equal(that interface{}) bool
- func (m *Watch) GetWatcher() *PID
- func (m *Watch) Marshal() (dAtA []byte, err error)
- func (m *Watch) MarshalTo(dAtA []byte) (int, error)
- func (m *Watch) MarshalToSizedBuffer(dAtA []byte) (int, error)
- func (*Watch) ProtoMessage()
- func (m *Watch) Reset()
- func (m *Watch) Size() (n int)
- func (this *Watch) String() string
- func (*Watch) SystemMessage()
- func (m *Watch) Unmarshal(dAtA []byte) error
- func (m *Watch) XXX_DiscardUnknown()
- func (m *Watch) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
- func (m *Watch) XXX_Merge(src proto.Message)
- func (m *Watch) XXX_Size() int
- func (m *Watch) XXX_Unmarshal(b []byte) error
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( ErrInvalidLengthProtos = fmt.Errorf("proto: negative length found during unmarshaling") ErrIntOverflowProtos = fmt.Errorf("proto: integer overflow") ErrUnexpectedEndOfGroupProtos = fmt.Errorf("proto: unexpected end of group") )
var (
EmptyMessageHeader = make(messageHeader)
)
var EmptyRootContext = &RootContext{ senderMiddleware: nil, spawnMiddleware: nil, headers: EmptyMessageHeader, guardianStrategy: nil, }
var ErrNameExists = errors.New("spawn: name exists")
ErrNameExists is the error used when an existing name is used for spawning an actor.
var ErrTimeout = errors.New("future: timeout")
ErrTimeout is the error used when a future times out before receiving a result.
var ProcessRegistry = &ProcessRegistryValue{ Address: localAddress, LocalPIDs: cmap.New(), }
ProcessRegistry is a registry of all active processes.
NOTE: This should only be used for advanced scenarios
Functions ¶
func SetLogLevel ¶
SetLogLevel sets the log level for the logger.
SetLogLevel is safe to call concurrently
func SetOptions ¶
func SetOptions(opts ...optionFn)
SetOptions is used to configure the actor system
func UnwrapEnvelope ¶
func UnwrapEnvelope(message interface{}) (ReadonlyMessageHeader, interface{}, *PID)
func UnwrapEnvelopeMessage ¶
func UnwrapEnvelopeMessage(message interface{}) interface{}
func WithDeadLetterSubscriber ¶
func WithDeadLetterSubscriber(fn func(evt interface{})) optionFn
WithDeadLetterSubscriber option replaces the default DeadLetterEvent event subscriber with fn.
fn will only receive *DeadLetterEvent messages
Specifying nil will clear the existing.
func WithSupervisorSubscriber ¶
func WithSupervisorSubscriber(fn func(evt interface{})) optionFn
WithSupervisorSubscriber option replaces the default SupervisorEvent event subscriber with fn.
fn will only receive *SupervisorEvent messages
Specifying nil will clear the existing.
Types ¶
type Actor ¶
type Actor interface {
Receive(c Context)
}
Actor is the interface that defines the Receive method.
Receive is sent messages to be processed from the mailbox associated with the instance of the actor
type ActorFunc ¶
type ActorFunc func(c Context)
The ActorFunc type is an adapter to allow the use of ordinary functions as actors to process messages
type ActorProcess ¶
type ActorProcess struct {
// contains filtered or unexported fields
}
func NewActorProcess ¶
func NewActorProcess(mailbox mailbox.Mailbox) *ActorProcess
func (*ActorProcess) SendSystemMessage ¶
func (ref *ActorProcess) SendSystemMessage(pid *PID, message interface{})
func (*ActorProcess) SendUserMessage ¶
func (ref *ActorProcess) SendUserMessage(pid *PID, message interface{})
func (*ActorProcess) Stop ¶
func (ref *ActorProcess) Stop(pid *PID)
type AddressResolver ¶
An AddressResolver is used to resolve remote actors
type AutoReceiveMessage ¶
type AutoReceiveMessage interface {
AutoReceiveMessage()
}
An AutoReceiveMessage is a special kind of user message that will be handled in some way automatically by the actor
type Behavior ¶
type Behavior []ActorFunc
func NewBehavior ¶
func NewBehavior() Behavior
func (*Behavior) BecomeStacked ¶
func (*Behavior) UnbecomeStacked ¶
func (b *Behavior) UnbecomeStacked()
type Context ¶
type Context interface {
// contains filtered or unexported methods
}
Context contains contextual information for actors
Example (SetReceiveTimeout) ¶
SetReceiveTimeout allows an actor to be notified repeatedly if it does not receive any messages for a specified duration
package main import ( "fmt" "sync" "time" "github.com/ChaokunChang/protoactor-go/actor" ) type setReceiveTimeoutActor struct { *sync.WaitGroup } // Receive is the default message handler when an actor is started func (f *setReceiveTimeoutActor) Receive(context actor.Context) { switch context.Message().(type) { case *actor.Started: // when the actor starts, set the receive timeout to 10 milliseconds. // // the system will send an *actor.ReceiveTimeout message every time the timeout // expires until SetReceiveTimeout is called again with a duration < 1 ms] context.SetReceiveTimeout(10 * time.Millisecond) case *actor.ReceiveTimeout: fmt.Println("timed out") f.Done() } } // SetReceiveTimeout allows an actor to be notified repeatedly if it does not receive any messages // for a specified duration func main() { wg := &sync.WaitGroup{} wg.Add(1) pid := actor.EmptyRootContext.Spawn(actor.PropsFromProducer(func() actor.Actor { return &setReceiveTimeoutActor{wg} })) defer func() { actor.EmptyRootContext.StopFuture(pid).Wait() }() wg.Wait() // wait for the ReceiveTimeout message }
Output: timed out
type ContextDecorator ¶
type ContextDecorator func(next ContextDecoratorFunc) ContextDecoratorFunc
type ContextDecoratorFunc ¶
type DeadLetterEvent ¶
type DeadLetterEvent struct { PID *PID // The invalid process, to which the message was sent Message interface{} // The message that could not be delivered Sender *PID // the process that sent the Message }
A DeadLetterEvent is published via event.Publish when a message is sent to a nonexistent PID
type DeciderFunc ¶
type DeciderFunc func(reason interface{}) Directive
DeciderFunc is a function which is called by a SupervisorStrategy
type Directive ¶
type Directive int
Directive is an enum for supervision actions
const ( // ResumeDirective instructs the supervisor to resume the actor and continue processing messages ResumeDirective Directive = iota // RestartDirective instructs the supervisor to discard the actor, replacing it with a new instance, // before processing additional messages RestartDirective // StopDirective instructs the supervisor to stop the actor StopDirective // EscalateDirective instructs the supervisor to escalate handling of the failure to the actor's parent supervisor EscalateDirective )
Directive determines how a supervisor should handle a faulting actor
func DefaultDecider ¶
func DefaultDecider(_ interface{}) Directive
DefaultDecider is a decider that will always restart the failing child actor
type Failure ¶
type Failure struct { Who *PID Reason interface{} RestartStats *RestartStatistics Message interface{} }
func (*Failure) SystemMessage ¶
func (*Failure) SystemMessage()
type Future ¶
type Future struct {
// contains filtered or unexported fields
}
func (*Future) PipeTo ¶
PipeTo forwards the result or error of the future to the specified pids
Example ¶
package main import ( "fmt" "sync" "time" "github.com/ChaokunChang/protoactor-go/actor" ) func main() { var wg sync.WaitGroup wg.Add(1) // test actor that will be the target of the future PipeTo pid := actor.EmptyRootContext.Spawn(actor.PropsFromFunc(func(ctx actor.Context) { // check if the message is a string and therefore // the "hello world" message piped from the future if m, ok := ctx.Message().(string); ok { fmt.Println(m) wg.Done() } })) f := actor.NewFuture(50 * time.Millisecond) f.PipeTo(pid) // resolve the future and pipe to waiting actor actor.EmptyRootContext.Send(f.PID(), "hello world") wg.Wait() }
Output: hello world
type InboundMiddleware
deprecated
type MessageEnvelope ¶
type MessageEnvelope struct { Header messageHeader Message interface{} Sender *PID }
func WrapEnvelope ¶
func WrapEnvelope(message interface{}) *MessageEnvelope
func (*MessageEnvelope) GetHeader ¶
func (me *MessageEnvelope) GetHeader(key string) string
func (*MessageEnvelope) SetHeader ¶
func (me *MessageEnvelope) SetHeader(key string, value string)
type NotInfluenceReceiveTimeout ¶
type NotInfluenceReceiveTimeout interface {
NotInfluenceReceiveTimeout()
}
NotInfluenceReceiveTimeout messages will not reset the ReceiveTimeout timer of an actor that receives the message
type OutboundMiddleware
deprecated
type OutboundMiddleware func(next SenderFunc) SenderFunc
Deprecated: Use SenderMiddleware instead
type PID ¶
type PID struct { Address string `protobuf:"bytes,1,opt,name=Address,proto3" json:"Address,omitempty"` Id string `protobuf:"bytes,2,opt,name=Id,proto3" json:"Id,omitempty"` // contains filtered or unexported fields }
func NewLocalPID ¶
NewLocalPID returns a new instance of the PID struct with the address preset
func Spawn ¶
Spawn starts a new actor based on props and named with a unique id Deprecated: Use context.Spawn instead.
Example ¶
Spawn creates instances of actors, similar to 'new' or 'make' but for actors.
package main import ( "fmt" "sync" "github.com/ChaokunChang/protoactor-go/actor" ) func main() { var wg sync.WaitGroup wg.Add(1) // create root context context := actor.EmptyRootContext // define the actor props // props define the creation process of an actor props := actor.PropsFromFunc(func(ctx actor.Context) { // check if the message is a *actor.Started message // this is the first message all actors get // actor.Started is received async and can be used // to initialize your actors initial state if _, ok := ctx.Message().(*actor.Started); ok { fmt.Println("hello world") wg.Done() } }) // spawn the actor based on the props context.Spawn(props) wg.Wait() }
Output: hello world
func SpawnNamed ¶
SpawnNamed starts a new actor based on props and named using the specified name
If name exists, error will be ErrNameExists Deprecated: Use context.SpawnNamed instead.
Example ¶
Spawn creates instances of actors, similar to 'new' or 'make' but for actors.
package main import ( "fmt" "log" "sync" "github.com/ChaokunChang/protoactor-go/actor" ) func main() { var wg sync.WaitGroup wg.Add(1) // create root context context := actor.EmptyRootContext // define the actor props // props define the creation process of an actor props := actor.PropsFromFunc(func(ctx actor.Context) { // check if the message is a *actor.Started message // this is the first message all actors get // actor.Started is received async and can be used // to initialize your actors initial state if _, ok := ctx.Message().(*actor.Started); ok { fmt.Println("hello world") wg.Done() } }) // spawn the actor based on the props _, err := context.SpawnNamed(props, "my-actor") if err != nil { log.Fatal("The actor name is already in use") } wg.Wait() }
Output: hello world
func SpawnPrefix ¶
SpawnPrefix starts a new actor based on props and named using a prefix followed by a unique id Deprecated: Use context.SpawnPrefix instead.
func UnwrapEnvelopeSender ¶
func UnwrapEnvelopeSender(message interface{}) *PID
func (*PID) Descriptor ¶
func (*PID) GetAddress ¶
func (*PID) GracefulPoison
deprecated
func (pid *PID) GracefulPoison()
GracefulPoison will tell and wait actor to stop after processing current user messages in mailbox.
Deprecated: Use Context.PoisonFuture(pid).Wait() instead
func (*PID) GracefulStop
deprecated
func (pid *PID) GracefulStop()
GracefulStop will stop actor immediately regardless of existing user messages in mailbox.
Deprecated: Use Context.StopFuture(pid).Wait() instead
func (*PID) PoisonFuture
deprecated
func (*PID) ProtoMessage ¶
func (*PID) ProtoMessage()
func (*PID) RequestFuture
deprecated
func (*PID) StopFuture
deprecated
func (*PID) XXX_DiscardUnknown ¶
func (m *PID) XXX_DiscardUnknown()
func (*PID) XXX_Unmarshal ¶
type PIDSet ¶
type PIDSet struct {
// contains filtered or unexported fields
}
type PoisonPill ¶
type PoisonPill struct { }
user messages
func (*PoisonPill) AutoReceiveMessage ¶
func (*PoisonPill) AutoReceiveMessage()
func (*PoisonPill) Descriptor ¶
func (*PoisonPill) Descriptor() ([]byte, []int)
func (*PoisonPill) Equal ¶
func (this *PoisonPill) Equal(that interface{}) bool
func (*PoisonPill) Marshal ¶
func (m *PoisonPill) Marshal() (dAtA []byte, err error)
func (*PoisonPill) MarshalToSizedBuffer ¶
func (m *PoisonPill) MarshalToSizedBuffer(dAtA []byte) (int, error)
func (*PoisonPill) ProtoMessage ¶
func (*PoisonPill) ProtoMessage()
func (*PoisonPill) Reset ¶
func (m *PoisonPill) Reset()
func (*PoisonPill) Size ¶
func (m *PoisonPill) Size() (n int)
func (*PoisonPill) String ¶
func (this *PoisonPill) String() string
func (*PoisonPill) Unmarshal ¶
func (m *PoisonPill) Unmarshal(dAtA []byte) error
func (*PoisonPill) XXX_DiscardUnknown ¶
func (m *PoisonPill) XXX_DiscardUnknown()
func (*PoisonPill) XXX_Marshal ¶
func (m *PoisonPill) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
func (*PoisonPill) XXX_Merge ¶
func (m *PoisonPill) XXX_Merge(src proto.Message)
func (*PoisonPill) XXX_Size ¶
func (m *PoisonPill) XXX_Size() int
func (*PoisonPill) XXX_Unmarshal ¶
func (m *PoisonPill) XXX_Unmarshal(b []byte) error
type Process ¶
type Process interface { SendUserMessage(pid *PID, message interface{}) SendSystemMessage(pid *PID, message interface{}) Stop(pid *PID) }
A Process is an interface that defines the base contract for interaction of actors
type ProcessRegistryValue ¶
type ProcessRegistryValue struct { SequenceID uint64 Address string LocalPIDs cmap.ConcurrentMap RemoteHandlers []AddressResolver }
func (*ProcessRegistryValue) Add ¶
func (pr *ProcessRegistryValue) Add(process Process, id string) (*PID, bool)
func (*ProcessRegistryValue) GetLocal ¶
func (pr *ProcessRegistryValue) GetLocal(id string) (Process, bool)
func (*ProcessRegistryValue) NextId ¶
func (pr *ProcessRegistryValue) NextId() string
func (*ProcessRegistryValue) RegisterAddressResolver ¶
func (pr *ProcessRegistryValue) RegisterAddressResolver(handler AddressResolver)
func (*ProcessRegistryValue) Remove ¶
func (pr *ProcessRegistryValue) Remove(pid *PID)
type Props ¶
type Props struct {
// contains filtered or unexported fields
}
Props represents configuration to define how an actor should be created
func FromProducer
deprecated
func FromSpawnFunc
deprecated
func PropsFromFunc ¶
PropsFromFunc creates a props with the given receive func assigned as the actor producer
func PropsFromProducer ¶
PropsFromProducer creates a props with the given actor producer assigned
func (*Props) WithContextDecorator ¶
func (props *Props) WithContextDecorator(contextDecorator ...ContextDecorator) *Props
WithContextDecorator assigns context decorator to the props
func (*Props) WithDispatcher ¶
func (props *Props) WithDispatcher(dispatcher mailbox.Dispatcher) *Props
WithDispatcher assigns a dispatcher to the props
func (*Props) WithGuardian ¶
func (props *Props) WithGuardian(guardian SupervisorStrategy) *Props
WithGuardian assigns a guardian strategy to the props
func (*Props) WithMailbox ¶
WithMailbox assigns the desired mailbox producer to the props
func (*Props) WithMiddleware
deprecated
func (props *Props) WithMiddleware(middleware ...InboundMiddleware) *Props
Deprecated: Use WithReceiverMiddleware instead
func (*Props) WithOutboundMiddleware
deprecated
func (props *Props) WithOutboundMiddleware(middleware ...OutboundMiddleware) *Props
Deprecated: Use WithSenderMiddleware instead
func (*Props) WithProducer ¶
WithProducer assigns a actor producer to the props
func (*Props) WithReceiverMiddleware ¶
func (props *Props) WithReceiverMiddleware(middleware ...ReceiverMiddleware) *Props
Assign one or more middleware to the props
func (*Props) WithSenderMiddleware ¶
func (props *Props) WithSenderMiddleware(middleware ...SenderMiddleware) *Props
func (*Props) WithSpawnFunc ¶
WithSpawnFunc assigns a custom spawn func to the props, this is mainly for internal usage
func (*Props) WithSpawnMiddleware ¶
func (props *Props) WithSpawnMiddleware(middleware ...SpawnMiddleware) *Props
func (*Props) WithSupervisor ¶
func (props *Props) WithSupervisor(supervisor SupervisorStrategy) *Props
WithSupervisor assigns a supervision strategy to the props
type ReadonlyMessageHeader ¶
type ReadonlyMessageHeader interface { Get(key string) string Keys() []string Length() int ToMap() map[string]string }
func UnwrapEnvelopeHeader ¶
func UnwrapEnvelopeHeader(message interface{}) ReadonlyMessageHeader
type ReceiveTimeout ¶
type ReceiveTimeout struct{}
A ReceiveTimeout message is sent to an actor after the Context.ReceiveTimeout duration has expired
type ReceiverContext ¶
type ReceiverContext interface {
// contains filtered or unexported methods
}
type ReceiverFunc ¶
type ReceiverFunc func(c ReceiverContext, envelope *MessageEnvelope)
type ReceiverMiddleware ¶
type ReceiverMiddleware func(next ReceiverFunc) ReceiverFunc
type Restart ¶
type Restart struct{}
Restart is message sent by the actor system to control the lifecycle of an actor
func (*Restart) SystemMessage ¶
func (*Restart) SystemMessage()
type RestartStatistics ¶
type RestartStatistics struct {
// contains filtered or unexported fields
}
RestartStatistics keeps track of how many times an actor have restarted and when
func NewRestartStatistics ¶
func NewRestartStatistics() *RestartStatistics
NewRestartStatistics construct a RestartStatistics
func (*RestartStatistics) Fail ¶
func (rs *RestartStatistics) Fail()
Fail increases the associated actors failure count
func (*RestartStatistics) FailureCount ¶
func (rs *RestartStatistics) FailureCount() int
FailureCount returns failure count
func (*RestartStatistics) NumberOfFailures ¶
func (rs *RestartStatistics) NumberOfFailures(withinDuration time.Duration) int
NumberOfFailures returns number of failures within a given duration
func (*RestartStatistics) Reset ¶
func (rs *RestartStatistics) Reset()
Reset the associated actors failure count
type Restarting ¶
type Restarting struct{}
A Restarting message is sent to an actor when the actor is being restarted by the system due to a failure
func (*Restarting) AutoReceiveMessage ¶
func (*Restarting) AutoReceiveMessage()
type RootContext ¶
type RootContext struct {
// contains filtered or unexported fields
}
func NewRootContext ¶
func NewRootContext(header map[string]string, middleware ...SenderMiddleware) *RootContext
func (*RootContext) Actor ¶
func (rc *RootContext) Actor() Actor
func (RootContext) Copy ¶
func (rc RootContext) Copy() *RootContext
func (*RootContext) Message ¶
func (rc *RootContext) Message() interface{}
func (*RootContext) MessageHeader ¶
func (rc *RootContext) MessageHeader() ReadonlyMessageHeader
func (*RootContext) Parent ¶
func (rc *RootContext) Parent() *PID
func (*RootContext) Poison ¶
func (rc *RootContext) Poison(pid *PID)
Poison will tell actor to stop after processing current user messages in mailbox.
func (*RootContext) PoisonFuture ¶
func (rc *RootContext) PoisonFuture(pid *PID) *Future
PoisonFuture will tell actor to stop after processing current user messages in mailbox, and return its future.
func (*RootContext) Request ¶
func (rc *RootContext) Request(pid *PID, message interface{})
func (*RootContext) RequestFuture ¶
func (rc *RootContext) RequestFuture(pid *PID, message interface{}, timeout time.Duration) *Future
RequestFuture sends a message to a given PID and returns a Future
func (*RootContext) RequestWithCustomSender ¶
func (rc *RootContext) RequestWithCustomSender(pid *PID, message interface{}, sender *PID)
func (*RootContext) Self ¶
func (rc *RootContext) Self() *PID
func (*RootContext) Send ¶
func (rc *RootContext) Send(pid *PID, message interface{})
func (*RootContext) Sender ¶
func (rc *RootContext) Sender() *PID
func (*RootContext) Spawn ¶
func (rc *RootContext) Spawn(props *Props) *PID
Spawn starts a new actor based on props and named with a unique id
func (*RootContext) SpawnNamed ¶
func (rc *RootContext) SpawnNamed(props *Props, name string) (*PID, error)
SpawnNamed starts a new actor based on props and named using the specified name
ErrNameExists will be returned if id already exists ¶
Please do not use name sharing same pattern with system actors, for example "YourPrefix$1", "Remote$1", "future$1"
func (*RootContext) SpawnPrefix ¶
func (rc *RootContext) SpawnPrefix(props *Props, prefix string) *PID
SpawnPrefix starts a new actor based on props and named using a prefix followed by a unique id
func (*RootContext) Stop ¶
func (rc *RootContext) Stop(pid *PID)
Stop will stop actor immediately regardless of existing user messages in mailbox.
func (*RootContext) StopFuture ¶
func (rc *RootContext) StopFuture(pid *PID) *Future
StopFuture will stop actor immediately regardless of existing user messages in mailbox, and return its future.
func (*RootContext) WithGuardian ¶
func (rc *RootContext) WithGuardian(guardian SupervisorStrategy) *RootContext
func (*RootContext) WithHeaders ¶
func (rc *RootContext) WithHeaders(headers map[string]string) *RootContext
func (*RootContext) WithSenderMiddleware ¶
func (rc *RootContext) WithSenderMiddleware(middleware ...SenderMiddleware) *RootContext
func (*RootContext) WithSpawnMiddleware ¶
func (rc *RootContext) WithSpawnMiddleware(middleware ...SpawnMiddleware) *RootContext
type SenderContext ¶
type SenderContext interface {
// contains filtered or unexported methods
}
type SenderFunc ¶
type SenderFunc func(c SenderContext, target *PID, envelope *MessageEnvelope)
type SenderMiddleware ¶
type SenderMiddleware func(next SenderFunc) SenderFunc
type SpawnFunc ¶
type SpawnFunc func(id string, props *Props, parentContext SpawnerContext) (*PID, error)
Props types
var DefaultSpawner SpawnFunc = defaultSpawner
DefaultSpawner this is a hacking way to allow Proto.Router access default spawner func
type SpawnMiddleware ¶
type SpawnerContext ¶
type SpawnerContext interface {
// contains filtered or unexported methods
}
type Started ¶
type Started struct{}
A Started message is sent to an actor once it has been started and ready to begin receiving messages.
func (*Started) SystemMessage ¶
func (*Started) SystemMessage()
type Stop ¶
type Stop struct { }
func (*Stop) Descriptor ¶
func (*Stop) ProtoMessage ¶
func (*Stop) ProtoMessage()
func (*Stop) SystemMessage ¶
func (*Stop) SystemMessage()
func (*Stop) XXX_DiscardUnknown ¶
func (m *Stop) XXX_DiscardUnknown()
func (*Stop) XXX_Unmarshal ¶
type Stopped ¶
type Stopped struct{}
A Stopped message is sent to the actor once it has been stopped. A stopped actor will receive no further messages
func (*Stopped) AutoReceiveMessage ¶
func (*Stopped) AutoReceiveMessage()
type Stopping ¶
type Stopping struct{}
A Stopping message is sent to an actor prior to the actor being stopped
func (*Stopping) AutoReceiveMessage ¶
func (*Stopping) AutoReceiveMessage()
type Supervisor ¶
type Supervisor interface { Children() []*PID EscalateFailure(reason interface{}, message interface{}) RestartChildren(pids ...*PID) StopChildren(pids ...*PID) ResumeChildren(pids ...*PID) }
Supervisor is an interface that is used by the SupervisorStrategy to manage child actor lifecycle
type SupervisorEvent ¶
SupervisorEvent is sent on the EventStream when a supervisor have applied a directive to a failing child actor
type SupervisorStrategy ¶
type SupervisorStrategy interface {
HandleFailure(supervisor Supervisor, child *PID, rs *RestartStatistics, reason interface{}, message interface{})
}
SupervisorStrategy is an interface that decides how to handle failing child actors
func DefaultSupervisorStrategy ¶
func DefaultSupervisorStrategy() SupervisorStrategy
func NewAllForOneStrategy ¶
func NewAllForOneStrategy(maxNrOfRetries int, withinDuration time.Duration, decider DeciderFunc) SupervisorStrategy
NewAllForOneStrategy returns a new SupervisorStrategy which applies the given fault Directive from the decider to the failing child and all its children.
This strategy is appropriate when the children have a strong dependency, such that and any single one failing would place them all into a potentially invalid state.
func NewExponentialBackoffStrategy ¶
func NewExponentialBackoffStrategy(backoffWindow time.Duration, initialBackoff time.Duration) SupervisorStrategy
NewExponentialBackoffStrategy creates a new Supervisor strategy that restarts a faulting child using an exponential back off algorithm:
delay =
func NewOneForOneStrategy ¶
func NewOneForOneStrategy(maxNrOfRetries int, withinDuration time.Duration, decider DeciderFunc) SupervisorStrategy
NewOneForOneStrategy returns a new Supervisor strategy which applies the fault Directive from the decider to the failing child process.
This strategy is applicable if it is safe to handle a single child in isolation from its peers or dependents
func NewRestartingStrategy ¶
func NewRestartingStrategy() SupervisorStrategy
func RestartingSupervisorStrategy ¶
func RestartingSupervisorStrategy() SupervisorStrategy
type SystemMessage ¶
type SystemMessage interface {
SystemMessage()
}
A SystemMessage message is reserved for specific lifecycle messages used by the actor system
type Terminated ¶
type Terminated struct { Who *PID `protobuf:"bytes,1,opt,name=who,proto3" json:"who,omitempty"` AddressTerminated bool `protobuf:"varint,2,opt,name=address_terminated,json=addressTerminated,proto3" json:"address_terminated,omitempty"` }
func (*Terminated) Descriptor ¶
func (*Terminated) Descriptor() ([]byte, []int)
func (*Terminated) Equal ¶
func (this *Terminated) Equal(that interface{}) bool
func (*Terminated) GetAddressTerminated ¶
func (m *Terminated) GetAddressTerminated() bool
func (*Terminated) GetWho ¶
func (m *Terminated) GetWho() *PID
func (*Terminated) Marshal ¶
func (m *Terminated) Marshal() (dAtA []byte, err error)
func (*Terminated) MarshalToSizedBuffer ¶
func (m *Terminated) MarshalToSizedBuffer(dAtA []byte) (int, error)
func (*Terminated) ProtoMessage ¶
func (*Terminated) ProtoMessage()
func (*Terminated) Reset ¶
func (m *Terminated) Reset()
func (*Terminated) Size ¶
func (m *Terminated) Size() (n int)
func (*Terminated) String ¶
func (this *Terminated) String() string
func (*Terminated) SystemMessage ¶
func (*Terminated) SystemMessage()
func (*Terminated) Unmarshal ¶
func (m *Terminated) Unmarshal(dAtA []byte) error
func (*Terminated) XXX_DiscardUnknown ¶
func (m *Terminated) XXX_DiscardUnknown()
func (*Terminated) XXX_Marshal ¶
func (m *Terminated) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
func (*Terminated) XXX_Merge ¶
func (m *Terminated) XXX_Merge(src proto.Message)
func (*Terminated) XXX_Size ¶
func (m *Terminated) XXX_Size() int
func (*Terminated) XXX_Unmarshal ¶
func (m *Terminated) XXX_Unmarshal(b []byte) error
type Unwatch ¶
type Unwatch struct {
Watcher *PID `protobuf:"bytes,1,opt,name=watcher,proto3" json:"watcher,omitempty"`
}
func (*Unwatch) Descriptor ¶
func (*Unwatch) GetWatcher ¶
func (*Unwatch) MarshalToSizedBuffer ¶
func (*Unwatch) ProtoMessage ¶
func (*Unwatch) ProtoMessage()
func (*Unwatch) SystemMessage ¶
func (*Unwatch) SystemMessage()
func (*Unwatch) XXX_DiscardUnknown ¶
func (m *Unwatch) XXX_DiscardUnknown()
func (*Unwatch) XXX_Marshal ¶
func (*Unwatch) XXX_Unmarshal ¶
type Watch ¶
type Watch struct {
Watcher *PID `protobuf:"bytes,1,opt,name=watcher,proto3" json:"watcher,omitempty"`
}
system messages
func (*Watch) Descriptor ¶
func (*Watch) GetWatcher ¶
func (*Watch) ProtoMessage ¶
func (*Watch) ProtoMessage()
func (*Watch) SystemMessage ¶
func (*Watch) SystemMessage()
func (*Watch) XXX_DiscardUnknown ¶
func (m *Watch) XXX_DiscardUnknown()
func (*Watch) XXX_Marshal ¶
func (*Watch) XXX_Unmarshal ¶
Source Files ¶
- actor.go
- actor_context.go
- actor_process.go
- behavior.go
- child_restart_stats.go
- context.go
- deadletter.go
- directive.go
- directive_string.go
- doc.go
- future.go
- guardian.go
- log.go
- message_envelope.go
- messages.go
- middleware_chain.go
- options.go
- pid.go
- pidset.go
- process.go
- process_registry.go
- props.go
- protos.pb.go
- root_context.go
- spawn.go
- strategy_all_for_one.go
- strategy_exponential_backoff.go
- strategy_one_for_one.go
- strategy_restarting.go
- supervision.go
- supervision_event.go