Control.Eff.Concurrent.Protocol.StatefulServer

Utilities to implement server-loops with builtin state and TEA-like naming.

Since: 0.24.0

Documentation

class Typeable (Protocol a) => Server (a :: Type) q where

A type class for server loops.

This class serves as interface for other mechanisms, for example process supervision

The methods of this class handle Events and Requests for Pdu instances.

Instances can by index types for Pdu family directly, or indirectly via the ServerPdu type family.

To builder servers serving multiple protocols, use the generic Pdu instances, for which Embeds instances exist, like 2-,3-,4-, or 5-tuple.

The naming is inspired by The Elm Architecture, without the view callback.

This class is based on Control.Eff.Concurrent.Protocol.EffectfulServer and adds a default State and Reader effect.

Since: 0.24.0

Minimal complete definition

update

Associated Types

data StartArgument a

The value that defines what is required to initiate a Server loop.

type Protocol a :: Type

The index type of the Events that this server processes. This is the first parameter to the Request and therefore of the Pdu family.

data Model a :: Type

Type of the model data, given to every invocation of update via the ModelState effect. The model of a server loop is changed through incoming Events. It is initially calculated by setup.

type Settings a :: Type

Type of read-only state.

Methods

title :: StartArgument a -> ProcessTitle

Return a new ProcessTitle for the stateful process, while it is running.

Since: 0.30.0

title :: Typeable a => StartArgument a -> ProcessTitle

Return a new ProcessTitle for the stateful process, while it is running.

Since: 0.30.0

setup :: Endpoint (Protocol a) -> StartArgument a -> Eff q (Model a, Settings a)

Return an initial Model and Settings

setup :: (Default (Model a), Default (Settings a)) => Endpoint (Protocol a) -> StartArgument a -> Eff q (Model a, Settings a)

Return an initial Model and Settings

update :: Endpoint (Protocol a) -> StartArgument a -> Event (Protocol a) -> Eff (ModelState a ': (SettingsReader a ': q)) ()

Update the Model based on the Event.

Instances

(Typeable event, Lifted IO q, Member Logs q) => Server (ObservationQueue event) (Processes q)

Defined in Control.Eff.Concurrent.Protocol.Observer.Queue

Associated Types

data StartArgument (ObservationQueue event) :: Type

type Protocol (ObservationQueue event) :: Type

data Model (ObservationQueue event) :: Type

type Settings (ObservationQueue event) :: Type

Methods

title :: StartArgument (ObservationQueue event) -> ProcessTitle

setup :: Endpoint (Protocol (ObservationQueue event)) -> StartArgument (ObservationQueue event) -> Eff (Processes q) (Model (ObservationQueue event), Settings (ObservationQueue event))

update :: Endpoint (Protocol (ObservationQueue event)) -> StartArgument (ObservationQueue event) -> Event (Protocol (ObservationQueue event)) -> Eff (ModelState (ObservationQueue event) ': (SettingsReader (ObservationQueue event) ': Processes q)) ()

(IoLogging q, TangibleBroker p, Tangible (ChildId p), Typeable (ServerPdu p), Server p (Processes q), HasProcesses (ServerEffects p (Processes q)) q) => Server (Broker p) (Processes q)

Defined in Control.Eff.Concurrent.Protocol.Broker

Associated Types

data StartArgument (Broker p) :: Type

type Protocol (Broker p) :: Type

data Model (Broker p) :: Type

type Settings (Broker p) :: Type

Methods

title :: StartArgument (Broker p) -> ProcessTitle

setup :: Endpoint (Protocol (Broker p)) -> StartArgument (Broker p) -> Eff (Processes q) (Model (Broker p), Settings (Broker p))

update :: Endpoint (Protocol (Broker p)) -> StartArgument (Broker p) -> Event (Protocol (Broker p)) -> Eff (ModelState (Broker p) ': (SettingsReader (Broker p) ': Processes q)) ()

(Typeable child, HasPdu (ServerPdu child), Tangible (ChildId child), Ord (ChildId child), Eq (ChildId child), Lifted IO e, Member Logs e) => Server (Watchdog child) (Processes e)

Defined in Control.Eff.Concurrent.Protocol.Watchdog

Associated Types

data StartArgument (Watchdog child) :: Type

type Protocol (Watchdog child) :: Type

data Model (Watchdog child) :: Type

type Settings (Watchdog child) :: Type

Methods

title :: StartArgument (Watchdog child) -> ProcessTitle

setup :: Endpoint (Protocol (Watchdog child)) -> StartArgument (Watchdog child) -> Eff (Processes e) (Model (Watchdog child), Settings (Watchdog child))

update :: Endpoint (Protocol (Watchdog child)) -> StartArgument (Watchdog child) -> Event (Protocol (Watchdog child)) -> Eff (ModelState (Watchdog child) ': (SettingsReader (Watchdog child) ': Processes e)) ()

data Stateful a

This type is used to build stateful EffectfulServer instances.

It is a variant of EffectfulServer, that comes pre-installed with State and Reader effects.

Since: 0.24.0

Instances

Server a q => Server (Stateful a) q

Defined in Control.Eff.Concurrent.Protocol.StatefulServer

Associated Types

data Init (Stateful a) :: Type

type ServerPdu (Stateful a) :: Type

type ServerEffects (Stateful a) q :: [Type -> Type]

Methods

serverTitle :: Init (Stateful a) -> ProcessTitle

runEffects :: Endpoint (ServerPdu (Stateful a)) -> Init (Stateful a) -> Eff (ServerEffects (Stateful a) q) x -> Eff q x

onEvent :: Endpoint (ServerPdu (Stateful a)) -> Init (Stateful a) -> Event (ServerPdu (Stateful a)) -> Eff (ServerEffects (Stateful a) q) ()

data Init (Stateful a)

Defined in Control.Eff.Concurrent.Protocol.StatefulServer

data Init (Stateful a) = Init (StartArgument a)

type ServerPdu (Stateful a)

Defined in Control.Eff.Concurrent.Protocol.StatefulServer

type ServerPdu (Stateful a) = Protocol a

type ChildId (Stateful p)

Defined in Control.Eff.Concurrent.Protocol.Broker

type ChildId (Stateful p) = ChildId p

type ServerEffects (Stateful a) q

Defined in Control.Eff.Concurrent.Protocol.StatefulServer

type ServerEffects (Stateful a) q = ModelState a ': (SettingsReader a ': q)

data family Init a

The value that defines what is required to initiate a Server loop.

Instances

TangibleCallbacks tag eLoop e => Show (Init (Server tag eLoop e))

Defined in Control.Eff.Concurrent.Protocol.CallbackServer

Methods

showsPrec :: Int -> Init (Server tag eLoop e) -> ShowS

show :: Init (Server tag eLoop e) -> String

showList :: [Init (Server tag eLoop e)] -> ShowS

TangibleCallbacks tag eLoop e => NFData (Init (Server tag eLoop e))

Defined in Control.Eff.Concurrent.Protocol.CallbackServer

Methods

rnf :: Init (Server tag eLoop e) -> ()

data Init (Stateful a)

Defined in Control.Eff.Concurrent.Protocol.StatefulServer

data Init (Stateful a) = Init (StartArgument a)

data Init (Server tag eLoop e)

Defined in Control.Eff.Concurrent.Protocol.CallbackServer

data Init (Server tag eLoop e) = MkServer {

• genServerId :: ServerId tag
• genServerRunEffects :: forall x. Endpoint tag -> Eff eLoop x -> Eff (Processes e) x
• genServerOnEvent :: Endpoint tag -> Event tag -> Eff eLoop ()

}

startLink :: forall a r q. (HasCallStack, Typeable a, FilteredLogging (Processes q), Server (Stateful a) (Processes q), Server a (Processes q), HasProcesses r q) => StartArgument a -> Eff r (Endpoint (Protocol a))

Execute the server loop.

Since: 0.24.0

start :: forall a r q. (HasCallStack, Typeable a, Server (Stateful a) (Processes q), Server a (Processes q), FilteredLogging (Processes q), HasProcesses r q) => StartArgument a -> Eff r (Endpoint (Protocol a))

Execute the server loop. Please use startLink if you can.

Since: 0.24.0

type ModelState a = State (Model a)

The Effect type of mutable Model in a Server instance.

Since: 0.24.0

modifyModel :: forall a e. Member (ModelState a) e => (Model a -> Model a) -> Eff e ()

Modify the Model of a Server.

Since: 0.24.0

getAndModifyModel :: forall a e. Member (ModelState a) e => (Model a -> Model a) -> Eff e (Model a)

Modify the Model of a Server and return the old value.

Since: 0.24.0

modifyAndGetModel :: forall a e. Member (ModelState a) e => (Model a -> Model a) -> Eff e (Model a)

Modify the Model of a Server and return the new value.

Since: 0.24.0

getModel :: forall a e. Member (ModelState a) e => Eff e (Model a)

Return the Model of a Server.

Since: 0.24.0

putModel :: forall a e. Member (ModelState a) e => Model a -> Eff e ()

Overwrite the Model of a Server.

Since: 0.24.0

getAndPutModel :: forall a e. Member (ModelState a) e => Model a -> Eff e (Model a)

Overwrite the Model of a Server, return the old value.

Since: 0.24.0

useModel :: forall a b e. Member (ModelState a) e => Getting b (Model a) b -> Eff e b

Return a element selected by a Lens of the Model of a Server.

Since: 0.24.0

preuseModel :: forall a b e. Member (ModelState a) e => Getting (First b) (Model a) b -> Eff e (Maybe b)

Return a element selected by a Lens of the Model of a Server.

Since: 0.30.0

zoomModel :: forall a b c e. Member (ModelState a) e => Lens' (Model a) b -> Eff (State b ': e) c -> Eff e c

Run an action that modifies portions of the Model of a Server defined by the given Lens.

Since: 0.24.0

logModel :: forall m e q. (Show (Model m), Member Logs e, HasProcesses e q, Member (ModelState m) e) => Text -> Eff e ()

Log the Model of a Server using logDebug.

Since: 0.30.0

type SettingsReader a = Reader (Settings a)

The Effect type of readonly Settings in a Server instance.

Since: 0.24.0

askSettings :: forall a e. Member (SettingsReader a) e => Eff e (Settings a)

Return the read-only Settings of a Server

Since: 0.24.0

viewSettings :: forall a b e. Member (SettingsReader a) e => Getting b (Settings a) b -> Eff e b

Return the read-only Settings of a Server as viewed through a Lens

Since: 0.24.0

mapEffects

Arguments

:: (Settings outer -> Settings inner)

A function to get the inner settings out of the outer settings

-> Lens' (Model outer) (Model inner)

A Lens to get and set the inner model inside the outer model

-> Eff (ModelState inner ': (SettingsReader inner ': e)) a

-> Eff (ModelState outer ': (SettingsReader outer ': e)) a

Map ModelState and SettingsReader effects. Use this to embed update from another Server instance.

Since: 0.30.0

coerceEffects :: forall inner outer a e. (Coercible (Model inner) (Model outer), Coercible (Model outer) (Model inner), Coercible (Settings outer) (Settings inner)) => Eff (ModelState inner ': (SettingsReader inner ': e)) a -> Eff (ModelState outer ': (SettingsReader outer ': e)) a

Coerce Coercible ModelState and SettingsReader effects. Use this to embed update from a similar Server instance.

Since: 0.30.0

Re-exports

data Event a where

This event sum-type is used to communicate incoming messages and other events to the instances of Server.

Since: 0.24.0

Constructors

OnCall :: forall a r. (Tangible r, TangiblePdu a (Synchronous r)) => ReplyTarget a r -> Pdu a (Synchronous r) -> Event a

A Synchronous message was received. If an implementation wants to delegate nested Pdus, it can use toEmbeddedReplyTarget to convert a ReplyTarget safely to the embedded protocol.

Since: 0.24.1

OnCast :: forall a. TangiblePdu a Asynchronous => Pdu a Asynchronous -> Event a

OnInterrupt :: Interrupt Recoverable -> Event a

OnDown :: ProcessDown -> Event a

OnTimeOut :: TimerElapsed -> Event a

OnMessage :: StrictDynamic -> Event a

Instances

Show (Event a)

Defined in Control.Eff.Concurrent.Protocol.EffectfulServer

Methods

showsPrec :: Int -> Event a -> ShowS

show :: Event a -> String

showList :: [Event a] -> ShowS

NFData a => NFData (Event a)

Defined in Control.Eff.Concurrent.Protocol.EffectfulServer

Methods

rnf :: Event a -> ()

type ToPretty (Event a :: Type)

Defined in Control.Eff.Concurrent.Protocol.EffectfulServer

type ToPretty (Event a :: Type) = ToPretty a <+> PutStr "event"