sdk-api-kotlin/dev.restate.sdk.kotlin

Package-level declarations

Types

sealed interface Awakeable<T> : DurableFuture<T>

An Awakeable is a special type of DurableFuture which can be arbitrarily completed by another service, by addressing it with its id.

AwakeableHandle

sealed interface AwakeableHandle

This class represents a handle to an Awakeable created in another service.

CallDurableFuture

sealed interface CallDurableFuture<T> : DurableFuture<T>

The DurableFuture returned by a Context.call.

Context

sealed interface Context

This interface exposes the Restate functionalities to Restate services. It can be used to interact with other Restate services, record non-deterministic closures, execute timers and synchronize with external systems.

DurableFuture

sealed interface DurableFuture<T>

A DurableFuture allows to await an asynchronous result. Once await is called, the execution waits until the asynchronous result is available.

DurablePromise

sealed interface DurablePromise<T>

A DurablePromise is a durable, distributed version of a Kotlin's Deferred, or more commonly of a future/promise. Restate keeps track of the DurablePromise across restarts/failures.

DurablePromiseHandle

sealed interface DurablePromiseHandle<T>

This class represents a handle to a DurablePromise created in another service.

HandlerRunner

class HandlerRunner<REQ, RES, CTX : Context> : HandlerRunner<REQ, RES>

Adapter class for dev.restate.sdk.endpoint.definition.HandlerRunner to use the Kotlin API.

InvocationHandle

sealed interface InvocationHandle<Res>

An invocation handle, that can be used to interact with a running invocation.

KotlinState

@ApiStatus.Experimental

interface KotlinState

Interface for accessing Virtual Object/Workflow state in the reflection-based API.

KRequest

@ApiStatus.Experimental

interface KRequest<Req, Res> : Request<Req, Res>

Kotlin-idiomatic request for invoking Restate services from within a handler.

KRequestBuilder

@ApiStatus.Experimental

class KRequestBuilder<SVC : Any>

Builder for creating type-safe requests from within a handler.

KtDurablePromiseKey

object ~~KtDurablePromiseKey~~

KtSerdes

object ~~KtSerdes~~

KtStateKey

object ~~KtStateKey~~

ObjectContext

sealed interface ObjectContext : SharedObjectContext

This interface can be used only within exclusive handlers of virtual objects. It extends Context adding access to the virtual object instance key-value state storage.

RestateClock

@ExperimentalTime

@ApiStatus.Experimental

interface RestateClock

RestateRandom

class RestateRandom(seed: Long) : Random

RetryPolicy

data class RetryPolicy(val initialDelay: Duration, val exponentiationFactor: Float, val maxDelay: Duration? = null, val maxAttempts: Int? = null, val maxDuration: Duration? = null)

Retry policy configuration.

SelectBuilder

sealed interface SelectBuilder<in R>

SelectClause

sealed interface SelectClause<T>

SharedObjectContext

sealed interface SharedObjectContext : Context

This interface can be used only within shared handlers of virtual objects. It extends Context adding access to the virtual object instance key-value state storage.

SharedWorkflowContext

sealed interface SharedWorkflowContext : SharedObjectContext

This interface can be used only within shared handlers of workflow. It extends Context adding access to the workflow instance key-value state storage and to the DurablePromise API.

UsePreviewContext

@Target(allowedTargets = [AnnotationTarget.CLASS, AnnotationTarget.FUNCTION])

annotation class UsePreviewContext

Opt-in annotation to use the preview of new context features.

WorkflowContext

sealed interface WorkflowContext : SharedWorkflowContext, ObjectContext

This interface can be used only within workflow handlers of workflow. It extends Context adding access to the workflow instance key-value state storage and to the DurablePromise API.

Properties

body

val HandlerRequest.body: Slice

bodyAsByteArray

val HandlerRequest.bodyAsByteArray: ByteArray

bodyAsByteBuffer

val HandlerRequest.bodyAsByteBuffer: ByteBuffer

headers

val HandlerRequest.headers: Map<String, String>

invocationId

val HandlerRequest.invocationId: InvocationId

openTelemetryContext

val HandlerRequest.openTelemetryContext: Context

Restate

@ExperimentalTime

@get:ApiStatus.Experimental

val Clock.Companion.Restate: RestateClock

Get RestateClock, that deterministically records the time.

Functions

awaitAll

suspend fun <T> awaitAll(vararg durableFutures: DurableFuture<T>): List<T>

awaitAll

suspend fun <T> Collection<DurableFuture<T>>.awaitAll(): List<T>

Like kotlinx.coroutines.awaitAll, but for DurableFuture.

awakeable

@ApiStatus.Experimental

inline suspend fun <T : Any> awakeable(): Awakeable<T>

@ApiStatus.Experimental

suspend fun <T : Any> awakeable(typeTag: TypeTag<T>): Awakeable<T>

Create an Awakeable, addressable through Awakeable.id.

awakeable

inline suspend fun <T : Any> Context.awakeable(): Awakeable<T>

Create an Awakeable, addressable through Awakeable.id.

awakeableHandle

@ApiStatus.Experimental

suspend fun awakeableHandle(id: String): AwakeableHandle

Create a new AwakeableHandle for the provided identifier.

call

suspend fun <Req, Res> Request<Req, Res>.call(context: Context): CallDurableFuture<Res>

Shorthand for Context.call

clock

@ExperimentalTime

@ApiStatus.Experimental

fun clock(): RestateClock

Get RestateClock, that deterministically records the time.

context

@ApiStatus.Experimental

suspend fun context(): Context

Get the current Restate Context from within a handler.

durablePromiseKey

inline fun <T> durablePromiseKey(name: String): DurablePromiseKey<T>

get

@ApiStatus.Experimental

inline suspend fun <T : Any> KotlinState.get(key: String): T?

Gets the state stored under key.

inline suspend fun <T : Any> SharedObjectContext.get(key: String): T?

invocationHandle

@ApiStatus.Experimental

inline suspend fun <R> invocationHandle(invocationId: String): InvocationHandle<R>

Get an InvocationHandle for an already existing invocation.

invocationHandle

inline fun <Res> Context.invocationHandle(invocationId: String): InvocationHandle<Res>

Get an InvocationHandle for an already existing invocation. This will let you interact with a running invocation, for example to cancel it or retrieve its result.

objectKey

@ApiStatus.Experimental

suspend fun objectKey(): String

Get the key of this Virtual Object.

promise

@ApiStatus.Experimental

suspend fun <T : Any> promise(key: DurablePromiseKey<T>): DurablePromise<T>

Create a DurablePromise for the given key.

promiseHandle

@ApiStatus.Experimental

suspend fun <T : Any> promiseHandle(key: DurablePromiseKey<T>): DurablePromiseHandle<T>

Create a new DurablePromiseHandle for the provided key.

random

@ApiStatus.Experimental

suspend fun random(): RestateRandom

Get the deterministic random instance.

request

@ApiStatus.Experimental

suspend fun request(): HandlerRequest

Get the current request information.

resolve

inline suspend fun <T : Any> AwakeableHandle.resolve(payload: T)

Complete with success the Awakeable.

retryPolicy

fun retryPolicy(init: RetryPolicy.Builder.() -> Unit): RetryPolicy

runAsync

@ApiStatus.Experimental

inline suspend fun <T : Any> runAsync(name: String = "", retryPolicy: RetryPolicy? = null, noinline block: suspend () -> T): DurableFuture<T>

Execute a closure asynchronously.

runAsync

inline suspend fun <T : Any> Context.runAsync(name: String = "", retryPolicy: RetryPolicy? = null, noinline block: suspend () -> T): DurableFuture<T>

Execute a closure asynchronously. This is like runBlock, but it returns a DurableFuture that you can combine and select.

runBlock

@ApiStatus.Experimental

inline suspend fun <T : Any> runBlock(name: String = "", retryPolicy: RetryPolicy? = null, noinline block: suspend () -> T): T

Execute a closure, recording the result value in the journal.

runBlock

inline suspend fun <T : Any> Context.runBlock(name: String = "", retryPolicy: RetryPolicy? = null, noinline block: suspend () -> T): T

Execute a closure, recording the result value in the journal. The result value will be re-played in case of re-invocation (e.g. because of failure recovery or suspension point) without re-executing the closure.

select