Skip to main content

workflow

This library provides tools required for authoring workflows.

Usage​

See the tutorial for writing your first workflow.

Timers​

The recommended way of scheduling timers is by using the sleep function. We've replaced setTimeout and clearTimeout with deterministic versions so these are also usable but have a limitation that they don't play well with cancellation scopes.

import { sleep } from '@temporalio/workflow';

export async function sleeper(ms = 100): Promise<void> {
  await sleep(ms);
  console.log('slept');
}

Activities​

To schedule Activities, use proxyActivities to obtain an Activity function and call.

import { proxyActivities } from '@temporalio/workflow';
import type * as activities from './activities';

const { sendEmail } = proxyActivities<typeof activities>({
  startToCloseTimeout: '1 minute',
});

export async function sampleWorkflow(): Promise<string> {
 await sendEmail("to@example.com","Hello, Temporal!");
}

Updates, Signals and Queries​

Use setHandler to set handlers for Updates, Signals, and Queries.

Update and Signal handlers can be either async or non-async functions. Update handlers may return a value, but signal handlers may not (return void or Promise<void>). You may use Activities, Timers, child Workflows, etc in Update and Signal handlers, but this should be done cautiously: for example, note that if you await async operations such as these in an Update or Signal handler, then you are responsible for ensuring that the workflow does not complete first.

Query handlers may not be async functions, and may not mutate any variables or use Activities, Timers, child Workflows, etc.

Implementation​

export const incrementSignal = wf.defineSignal<[number]>('increment');
export const getValueQuery = wf.defineQuery<number>('getValue');
export const incrementAndGetValueUpdate = wf.defineUpdate<number, [number]>('incrementAndGetValue');

export async function counterWorkflow(initialValue: number): Promise<void> {
  let count = initialValue;
  wf.setHandler(incrementSignal, (arg: number) => {
    count += arg;
  });
  wf.setHandler(getValueQuery, () => count);
  wf.setHandler(incrementAndGetValueUpdate, (arg: number): number => {
    count += arg;
    return count;
  });
  await wf.condition(() => false);
}

More​

Classes​

Interfaces​

Type Aliases​

ActivityFunctionWithOptions​

ActivityFunctionWithOptions<T> = T & object

Type Parameters​

T​

T extends ActivityFunction

Type Declaration​

executeWithOptions()​

executeWithOptions(options, args): Promise<Awaited<ReturnType<T>>>

Experimental

Execute the activity, overriding its existing options with the provided options.

Parameters​
options​

ActivityOptions

ActivityOptions

args​

Parameters<T>

list of arguments

Returns​

Promise<Awaited<ReturnType<T>>>

return value of the activity

executeWithOptions is a new method to provide call-site options and is subject to change

ActivityInterfaceFor​

ActivityInterfaceFor<T> = { [K in keyof T]: T[K] extends ActivityFunction ? ActivityFunctionWithOptions<T[K]> : typeof NotAnActivityMethod }

Type helper that takes a type T and transforms attributes that are not ActivityFunction to NotAnActivityMethod.

Type Parameters​

T​

T

Example​

Used by proxyActivities to get this compile-time error:

interface MyActivities {
  valid(input: number): Promise<number>;
  invalid(input: number): number;
}

const act = proxyActivities<MyActivities>({ startToCloseTimeout: '5m' });

await act.valid(true);
await act.invalid();
// ^ TS complains with:
// (property) invalidDefinition: typeof NotAnActivityMethod
// This expression is not callable.
// Type 'Symbol' has no call signatures.(2349)

ChildWorkflowCancellationType​

ChildWorkflowCancellationType = typeof ChildWorkflowCancellationType[keyof typeof ChildWorkflowCancellationType]

Determines:

  • whether cancellation requests should be propagated from the Parent Workflow to the Child, and
  • whether and when should the Child's cancellation be reported back to the Parent Workflow (i.e. at which moment should the executeChild's or ChildWorkflowHandle.result's promise fail with a ChildWorkflowFailure, with cause set to a CancelledFailure).

Note that this setting only applies to cancellation originating from an external request for the Parent Workflow itself, or from internal cancellation of the CancellationScope in which the Child Workflow call was made. Eventual Cancellation of a Child Workflow on completion of the Parent Workflow is controlled by the ParentClosePolicy setting.

Default​

ChildWorkflowCancellationType.WAIT_CANCELLATION_COMPLETED

ConcludeActivationOutput​

ConcludeActivationOutput = ConcludeActivationInput

Output for WorkflowInternalsInterceptor.concludeActivation

ContinueAsNewInputOptions​

ContinueAsNewInputOptions = ContinueAsNewOptions & Required<Pick<ContinueAsNewOptions, "workflowType">>

Input for WorkflowOutboundCallsInterceptor.continueAsNew.

GetLogAttributesInput​

GetLogAttributesInput = Record<string, unknown>

Input for WorkflowOutboundCallsInterceptor.getLogAttributes.

GetMetricTagsInput​

GetMetricTagsInput = MetricTags

Input for WorkflowOutboundCallsInterceptor.getMetricTags.

LocalActivityFunctionWithOptions​

LocalActivityFunctionWithOptions<T> = T & object

Type Parameters​

T​

T extends ActivityFunction

Type Declaration​

executeWithOptions()​

executeWithOptions(options, args): Promise<Awaited<ReturnType<T>>>

Experimental

Run the local activity, overriding its existing options with the provided options.

Parameters​
options​

LocalActivityOptions

LocalActivityOptions

args​

Parameters<T>

list of arguments

Returns​

Promise<Awaited<ReturnType<T>>>

return value of the activity

executeWithOptions is a new method to provide call-site options and is subject to change

LocalActivityInterfaceFor​

LocalActivityInterfaceFor<T> = { [K in keyof T]: T[K] extends ActivityFunction ? LocalActivityFunctionWithOptions<T[K]> : typeof NotAnActivityMethod }

The local activity counterpart to ActivityInterfaceFor

Type Parameters​

T​

T

NexusOperationCancellationType​

NexusOperationCancellationType = typeof NexusOperationCancellationType[keyof typeof NexusOperationCancellationType]

Determines:

  • whether cancellation requests should be propagated from the Workflow to the Nexus Operation
  • whether and when should the Operation's cancellation be reported back to the Workflow (i.e. at which moment should the operation's result promise fail with a NexusOperationFailure, with cause set to a CancelledFailure).

Note that this setting only applies to cancellation originating from an external request for the Workflow itself, or from internal cancellation of the CancellationScope in which the Operation call was made.

ParentClosePolicy​

ParentClosePolicy = typeof ParentClosePolicy[keyof typeof ParentClosePolicy]

How a Child Workflow reacts to the Parent Workflow reaching a Closed state.

See​

Parent Close Policy

SignalWithStartWorkflowRequest​

SignalWithStartWorkflowRequest<WorkflowFn, SignalValue, SignalArgs> = ReplaceSignalWithStartWorkflowRequest<{ args?: ReadonlyArray<unknown> | Readonly<Parameters<WorkflowFn>>; cronSchedule?: string; executionTimeout?: Duration; headers?: Record<string, unknown>; id: string; idConflictPolicy?: WorkflowIdConflictPolicy; idReusePolicy?: WorkflowIdReusePolicy; memo?: Record<string, unknown>; namespace: string; priority?: Priority; retryPolicy?: RetryPolicy; runTimeout?: Duration; searchAttributes?: TypedSearchAttributes; signal: string | SignalValue; signalArgs?: ReadonlyArray<unknown> | Readonly<SignalArgs>; startDelay?: Duration; staticDetails?: string; staticSummary?: string; taskQueue: string; taskTimeout?: Duration; versioningOverride?: VersioningOverride; workflow: string | WorkflowFn; }, { args?: ReadonlyArray<unknown>; workflow: string; } | object & Parameters<WorkflowFn> extends [any, ...(...)[]] ? object : object & { signal: string; signalArgs?: ReadonlyArray<unknown>; } | object & SignalArgs extends [any, ...(...)[]] ? object : object>

Experimental

This API is experimental and subject to change.

Type Parameters​

WorkflowFn​

WorkflowFn extends (...args) => Promise<any> = (...args) => Promise<any>

SignalValue​

SignalValue extends SignalDefinition<any[]> = SignalDefinition<any[]>

SignalArgs​

SignalArgs extends any[] = SignalValue extends SignalDefinition<infer Args, any> ? Args : never

Sink​

Sink = Record<string, SinkFunction>

A mapping of name to function, defines a single sink (e.g. logger)

SinkFunction​

SinkFunction = (...args) => void

Any function signature can be used for Sink functions as long as the return type is void.

When calling a Sink function, arguments are copied from the Workflow isolate to the Node.js environment using postMessage.

This constrains the argument types to primitives (excluding Symbols).

Parameters​

args​

...any[]

Returns​

void

Sinks​

Sinks = Record<string, Sink>

Workflow Sink are a mapping of name to Sink

WorkflowInterceptorsFactory​

WorkflowInterceptorsFactory = () => WorkflowInterceptors

A function that instantiates WorkflowInterceptors.

Workflow interceptor modules should export an interceptors function of this type.

Returns​

WorkflowInterceptors

Example​

export function interceptors(): WorkflowInterceptors {
  return {
    inbound: [],   // Populate with list of inbound interceptor implementations
    outbound: [],  // Populate with list of outbound interceptor implementations
    internals: [], // Populate with list of internals interceptor implementations
  };
}

Variables​

AsyncLocalStorage​

const AsyncLocalStorage: <T>() => ALS<T>

Returns​

ALS<T>

ChildWorkflowCancellationType​

const ChildWorkflowCancellationType: object

Determines:

  • whether cancellation requests should be propagated from the Parent Workflow to the Child, and
  • whether and when should the Child's cancellation be reported back to the Parent Workflow (i.e. at which moment should the executeChild's or ChildWorkflowHandle.result's promise fail with a ChildWorkflowFailure, with cause set to a CancelledFailure).

Note that this setting only applies to cancellation originating from an external request for the Parent Workflow itself, or from internal cancellation of the CancellationScope in which the Child Workflow call was made. Eventual Cancellation of a Child Workflow on completion of the Parent Workflow is controlled by the ParentClosePolicy setting.

Type Declaration​

ABANDON​

readonly ABANDON: "ABANDON"

Do not propagate cancellation requests to the Child, and immediately report cancellation to the caller.

TRY_CANCEL​

readonly TRY_CANCEL: "TRY_CANCEL"

Propagate cancellation request from the Parent Workflow to the Child, yet immediately report cancellation to the caller, i.e. without waiting for the server to confirm the cancellation request.

Note that this cancellation type provides no guarantee, from the Parent-side, that the cancellation request will actually be atomically added to the Child workflow's history. In particular, the Child may complete (either successfully or uncessfully) before the cancellation is delivered, resulting in a situation where the Parent workflow thinks its child was cancelled, but the child actually completed successfully.

To guarantee that the Child will eventually be notified of the cancellation request, use WAIT_CANCELLATION_REQUESTED.

WAIT_CANCELLATION_COMPLETED​

readonly WAIT_CANCELLATION_COMPLETED: "WAIT_CANCELLATION_COMPLETED"

Propagate cancellation request from the Parent Workflow to the Child, then wait for completion of the Child Workflow.

The Child may respect cancellation, in which case the Parent's executeChild or ChildWorkflowHandle.result promise will fail with a ChildWorkflowFailure, with cause set to a CancelledFailure. On the other hand, the Child may ignore the cancellation request, in which case the corresponding promise will either resolve with a result (if Child completed successfully) or reject with a different cause (if Child completed uncessfully).

Default​
WAIT_CANCELLATION_REQUESTED​

readonly WAIT_CANCELLATION_REQUESTED: "WAIT_CANCELLATION_REQUESTED"

Propagate cancellation request from the Parent Workflow to the Child, then wait for the server to confirm that the Child Workflow cancellation request was recorded in its history.

This cancellation type guarantees that the Child will eventually be notified of the cancellation request (that is, unless the Child terminates inbetween due to unexpected causes).

Default​

ChildWorkflowCancellationType.WAIT_CANCELLATION_COMPLETED

enhancedStackTraceQuery​

const enhancedStackTraceQuery: QueryDefinition<EnhancedStackTrace, [], string>

log​

const log: WorkflowLogger

Default workflow logger.

This logger is replay-aware and will omit log messages on workflow replay. Messages emitted by this logger are funnelled through a sink that forwards them to the logger registered on Runtime.logger.

Attributes from the current Workflow Execution context are automatically included as metadata on every log entries. An extra sdkComponent metadata attribute is also added, with value workflow; this can be used for fine-grained filtering of log entries further downstream.

To customize log attributes, register a WorkflowOutboundCallsInterceptor that intercepts the getLogAttributes() method.

Notice that since sinks are used to power this logger, any log attributes must be transferable via the postMessage API.

NOTE: Specifying a custom logger through defaultSink or by manually registering a sink named defaultWorkerLogger has been deprecated. Please use Runtime.logger instead.

metricMeter​

const metricMeter: MetricMeter

Experimental

A MetricMeter that can be used to emit metrics from within a Workflow.

The Metric API is an experimental feature and may be subject to change.

NexusOperationCancellationType​

const NexusOperationCancellationType: object

Determines:

  • whether cancellation requests should be propagated from the Workflow to the Nexus Operation
  • whether and when should the Operation's cancellation be reported back to the Workflow (i.e. at which moment should the operation's result promise fail with a NexusOperationFailure, with cause set to a CancelledFailure).

Note that this setting only applies to cancellation originating from an external request for the Workflow itself, or from internal cancellation of the CancellationScope in which the Operation call was made.

Type Declaration​

ABANDON​

readonly ABANDON: "ABANDON"

Do not propagate cancellation requests to the Nexus Operation, and immediately report cancellation to the caller.

TRY_CANCEL​

readonly TRY_CANCEL: "TRY_CANCEL"

Initiate a cancellation request for the Nexus operation and immediately report cancellation to the caller. Note that it doesn't guarantee that cancellation is delivered to the operation if calling workflow exits before the delivery is done. If you want to ensure that cancellation is delivered to the operation, use WAIT_CANCELLATION_REQUESTED.

Propagate cancellation request from the Workflow to the Operation, yet immediately report cancellation to the caller, i.e. without waiting for the server to confirm the cancellation request.

Note that this cancellation type provides no guarantee, from the Workflow-side, that the cancellation request will be delivered to the Operation Handler. In particular, either the Operation or the Workflow may complete (either successfully or uncessfully) before the cancellation request is delivered, resulting in a situation where the Operation completed successfully, but the Workflow thinks it was cancelled.

To guarantee that the Operation will eventually be notified of the cancellation request, use WAIT_CANCELLATION_REQUESTED.

WAIT_CANCELLATION_COMPLETED​

readonly WAIT_CANCELLATION_COMPLETED: "WAIT_CANCELLATION_COMPLETED"

Propagate cancellation request from the Workflow to the Operation, then wait for completion of the Operation.

WAIT_CANCELLATION_REQUESTED​

readonly WAIT_CANCELLATION_REQUESTED: "WAIT_CANCELLATION_REQUESTED"

Propagate cancellation request from the Workflow to the Operation, then wait for the server to confirm that the Operation cancellation request was delivered to the Operation Handler.

NotAnActivityMethod​

const NotAnActivityMethod: unique symbol

Symbol used in the return type of proxy methods to mark that an attribute on the source type is not a method.

See​

ParentClosePolicy​

const ParentClosePolicy: object

How a Child Workflow reacts to the Parent Workflow reaching a Closed state.

Type Declaration​

ABANDON​

readonly ABANDON: "ABANDON"

When the Parent is Closed, nothing is done to the Child.

PARENT_CLOSE_POLICY_ABANDON​

readonly PARENT_CLOSE_POLICY_ABANDON: "ABANDON"

When the Parent is Closed, nothing is done to the Child.

Deprecated​

Use ParentClosePolicy.ABANDON instead.

PARENT_CLOSE_POLICY_REQUEST_CANCEL​

readonly PARENT_CLOSE_POLICY_REQUEST_CANCEL: "REQUEST_CANCEL"

When the Parent is Closed, the Child is Cancelled.

Deprecated​

Use ParentClosePolicy.REQUEST_CANCEL instead.

PARENT_CLOSE_POLICY_TERMINATE​

readonly PARENT_CLOSE_POLICY_TERMINATE: "TERMINATE"

When the Parent is Closed, the Child is Terminated.

Deprecated​

Use ParentClosePolicy.TERMINATE instead.

PARENT_CLOSE_POLICY_UNSPECIFIED​

readonly PARENT_CLOSE_POLICY_UNSPECIFIED: undefined

If a ParentClosePolicy is set to this, or is not set at all, the server default value will be used.

Deprecated​

Either leave property undefined, or set an explicit policy instead.

REQUEST_CANCEL​

readonly REQUEST_CANCEL: "REQUEST_CANCEL"

When the Parent is Closed, the Child is Cancelled.

TERMINATE​

readonly TERMINATE: "TERMINATE"

When the Parent is Closed, the Child is Terminated.

Default​

See​

Parent Close Policy

stackTraceQuery​

const stackTraceQuery: QueryDefinition<string, [], string>

workflowMetadataQuery​

const workflowMetadataQuery: QueryDefinition<IWorkflowMetadata, [], string>

workflowRandom​

const workflowRandom: WorkflowRandomStream

Experimental

The default deterministic random stream for the current workflow execution.

This exposes the same underlying sequence used by workflow-level Math.random() when no named override is active. It can be useful for plugin/interceptor code that wants an explicit handle to the main workflow random stream, including from inside a temporary named scope established by another WorkflowRandomStream.

This API may be removed or changed in the future.

Functions​

addDefaultWorkflowOptions()​

addDefaultWorkflowOptions<T>(opts): ChildWorkflowOptionsWithDefaults

Adds default values of workflowId and cancellationType to given workflow options.

Type Parameters​

T​

T extends Workflow

Parameters​

opts​

WithWorkflowArgs<T, ChildWorkflowOptions>

Returns​

ChildWorkflowOptionsWithDefaults

allHandlersFinished()​

allHandlersFinished(): boolean

Whether update and signal handlers have finished executing.

Consider waiting on this condition before workflow return or continue-as-new, to prevent interruption of in-progress handlers by workflow exit:

await workflow.condition(workflow.allHandlersFinished)

Returns​

boolean

true if there are no in-progress update or signal handler executions.

condition()​

Call Signature​

condition(fn, timeout, options): Promise<boolean>

Experimental

Returns a Promise that resolves when fn evaluates to true or timeout expires, providing options to configure the timer (i.e. provide metadata)

Parameters​
fn​

() => boolean

timeout​

Duration

number of milliseconds or ms-formatted string

options​

TimerOptions

Returns​

Promise<boolean>

a boolean indicating whether the condition was true before the timeout expires

TimerOptions is a new addition and subject to change

Call Signature​

condition(fn, timeout): Promise<boolean>

Returns a Promise that resolves when fn evaluates to true or timeout expires.

Parameters​
fn​

() => boolean

timeout​

Duration

number of milliseconds or ms-formatted string

Returns​

Promise<boolean>

a boolean indicating whether the condition was true before the timeout expires

Call Signature​

condition(fn): Promise<void>

Returns a Promise that resolves when fn evaluates to true.

Parameters​
fn​

() => boolean

Returns​

Promise<void>

continueAsNew()​

continueAsNew<F>(...args): Promise<never>

Continues-As-New the current Workflow Execution with default options.

Shorthand for makeContinueAsNewFunc<F>()(...args). (See: makeContinueAsNewFunc.)

Type Parameters​

F​

F extends Workflow

Parameters​

args​

...Parameters<F>

Returns​

Promise<never>

Example​

import { continueAsNew } from '@temporalio/workflow';
import { SearchAttributeType } from '@temporalio/common';

export async function myWorkflow(n: number): Promise<void> {
  // ... Workflow logic
  await continueAsNew<typeof myWorkflow>(n + 1);
}

createEventGroup()​

createEventGroup(id, options?): EventGroup

Experimental

Create an Event Group that can be attached to commands scheduled by this Workflow.

Attach the returned group via command eventGroups options, or via EventGroup.withScope.

Parameters​

id​

string

non-empty group identity. Commands with the same id belong to the same group. The user-provided ID is stored as plain text in the workflow history and should therefore not contain sensitive information.

options?​
label?​

string

optional non-empty display text for the UI / CLI. If provided, it is persisted to history as a codec-encoded Payload.

Event Groups is an experimental API and may change without notice.

Returns​

EventGroup

createNexusServiceClient()​

createNexusServiceClient<T>(options): NexusServiceClient<T>

Create a Nexus client for invoking Nexus Operations from a Workflow.

Type Parameters​

T​

T extends ServiceDefinition<OperationMap>

Parameters​

options​

NexusServiceClientOptions<T>

Returns​

NexusServiceClient<T>

currentUpdateInfo()​

currentUpdateInfo(): UpdateInfo | undefined

Get information about the current update if any.

Returns​

UpdateInfo | undefined

Info for the current update handler the code calling this is executing within if any.

defineQuery()​

defineQuery<Ret, Args, Name>(name, options?): QueryDefinition<Ret, Args, Name>

Define a query method for a Workflow.

A definition is used to register a handler in the Workflow via setHandler and to query a Workflow using a WorkflowHandle. A definition can be reused in multiple Workflows.

Type Parameters​

Ret​

Ret

Args​

Args extends any[] = []

Name​

Name extends string = string

Parameters​

name​

Name

options?​

QueryDefinitionOptions

Returns​

QueryDefinition<Ret, Args, Name>

defineSignal()​

defineSignal<Args, Name>(name, options?): SignalDefinition<Args, Name>

Define a signal method for a Workflow.

A definition is used to register a handler in the Workflow via setHandler and to signal a Workflow using a WorkflowHandle, ChildWorkflowHandle or ExternalWorkflowHandle. A definition can be reused in multiple Workflows.

Type Parameters​

Args​

Args extends any[] = []

Name​

Name extends string = string

Parameters​

name​

Name

options?​

SignalDefinitionOptions

optional type information used to convert Signal arguments

Returns​

SignalDefinition<Args, Name>

defineUpdate()​

defineUpdate<Ret, Args, Name>(name, options?): UpdateDefinition<Ret, Args, Name>

Define an update method for a Workflow.

A definition is used to register a handler in the Workflow via setHandler and to update a Workflow using a WorkflowHandle, ChildWorkflowHandle or ExternalWorkflowHandle. A definition can be reused in multiple Workflows.

Type Parameters​

Ret​

Ret

Args​

Args extends any[] = []

Name​

Name extends string = string

Parameters​

name​

Name

options?​

UpdateDefinitionOptions

Returns​

UpdateDefinition<Ret, Args, Name>

defineWorkflowOptions()​

defineWorkflowOptions<A, RT>(fn, config): void

Experimental

Attach per-execution options and static metadata to a Workflow function.

Static options are available before the Workflow function's arguments are decoded.

Type Parameters​

A​

A extends any[]

RT​

RT

Parameters​

fn​

(...args) => Promise<RT>

config​

WorkflowDefinitionConfig

Returns​

void

deprecatePatch()​

deprecatePatch(patchId, options?): void

Indicate that a patch is being phased out.

See docs page for info.

Workflows with this call may be deployed alongside workflows with a patched call, but they must not be deployed while any workers still exist running old code without a patched call, or any runs with histories produced by such workers exist. If either kind of worker encounters a history produced by the other, their behavior is undefined.

Once all live workflow runs have been produced by workers with this call, you can deploy workers which are free of either kind of patch call for this ID. Workers with and without this call may coexist, as long as they are both running the "new" code.

Parameters​

patchId​

string

An identifier that should be unique to this patch. It is OK to use multiple calls with the same ID, which means all such calls will always return the same value.

options?​

EventGroupsOptions

Returns​

void

executeChild()​

Call Signature​

executeChild<T>(workflowType, options): Promise<WorkflowResultType<T>>

Start a child Workflow execution and await its completion.

  • By default, a child will be scheduled on the same task queue as its parent.
  • This operation is cancellable using CancellationScopes.
Type Parameters​
T​

T extends Workflow

Parameters​
workflowType​

string

options​

WithWorkflowArgs<T, ChildWorkflowOptions>

Returns​

Promise<WorkflowResultType<T>>

The result of the child Workflow.

Call Signature​

executeChild<T>(workflowFunc, options): Promise<WorkflowResultType<T>>

Start a child Workflow execution and await its completion.

  • By default, a child will be scheduled on the same task queue as its parent.
  • Deduces the Workflow type and signature from provided Workflow function.
  • This operation is cancellable using CancellationScopes.
Type Parameters​
T​

T extends Workflow

Parameters​
workflowFunc​

T

options​

WithWorkflowArgs<T, ChildWorkflowDefinitionOptions>

Returns​

Promise<WorkflowResultType<T>>

The result of the child Workflow.

Call Signature​

executeChild<T>(workflowType): Promise<WorkflowResultType<T>>

Start a child Workflow execution and await its completion.

Override for Workflows that accept no arguments.

  • The child will be scheduled on the same task queue as its parent.
  • This operation is cancellable using CancellationScopes.
Type Parameters​
T​

T extends () => WorkflowReturnType

Parameters​
workflowType​

string

Returns​

Promise<WorkflowResultType<T>>

The result of the child Workflow.

Call Signature​

executeChild<T>(workflowFunc): Promise<WorkflowResultType<T>>

Start a child Workflow execution and await its completion.

Override for Workflows that accept no arguments.

  • The child will be scheduled on the same task queue as its parent.
  • Deduces the Workflow type and signature from provided Workflow function.
  • This operation is cancellable using CancellationScopes.
Type Parameters​
T​

T extends () => WorkflowReturnType

Parameters​
workflowFunc​

T

Returns​

Promise<WorkflowResultType<T>>

The result of the child Workflow.

getCurrentDetails()​

getCurrentDetails(): string

Returns​

string

getExternalWorkflowHandle()​

getExternalWorkflowHandle(workflowId, runId?): ExternalWorkflowHandle

Returns a client-side handle that can be used to signal and cancel an existing Workflow execution. It takes a Workflow ID and optional run ID.

Parameters​

workflowId​

string

runId?​

string

Returns​

ExternalWorkflowHandle

getRandomStream()​

getRandomStream(name): WorkflowRandomStream

Experimental

Get a named deterministic random stream for the current workflow execution.

Named streams are derived from the workflow seed and a stable stream name, without consuming the workflow's default Math.random() stream. Repeated calls with the same name within a workflow execution refer to the same logical stream state, including across activations.

This is the preferred entry point for workflow plugins and interceptors that need their own deterministic entropy. Use stable package- or module-style names so the stream identity remains replay-safe, then keep the returned WorkflowRandomStream around and call its methods directly.

This API may be removed or changed in the future.

Parameters​

name​

string

Returns​

WorkflowRandomStream

inWorkflowContext()​

inWorkflowContext(): boolean

Returns whether or not code is executing in workflow context

Returns​

boolean

isCancellation()​

isCancellation(err): boolean

Returns whether provided err is caused by cancellation

Parameters​

err​

unknown

Returns​

boolean

makeContinueAsNewFunc()​

makeContinueAsNewFunc<F>(options?): (...args) => Promise<never>

Returns a function f that will cause the current Workflow to ContinueAsNew when called.

f takes the same arguments as the Workflow function supplied to typeparam F.

Once f is called, Workflow Execution immediately completes.

Type Parameters​

F​

F extends Workflow

Parameters​

options?​

ContinueAsNewOptions

Returns​

(...args) => Promise<never>

patched()​

patched(patchId, options?): boolean

Patch or upgrade workflow code by checking or stating that this workflow has a certain patch.

See docs page for info.

If the workflow is replaying an existing history, then this function returns true if that history was produced by a worker which also had a patched call with the same patchId. If the history was produced by a worker without such a call, then it will return false.

If the workflow is not currently replaying, then this call always returns true.

Your workflow code should run the "new" code if this returns true, if it returns false, you should run the "old" code. By doing this, you can maintain determinism.

Parameters​

patchId​

string

An identifier that should be unique to this patch. It is OK to use multiple calls with the same ID, which means all such calls will always return the same value.

options?​

EventGroupsOptions

Returns​

boolean

proxyActivities()​

proxyActivities<A>(options): ActivityInterfaceFor<A>

Configure Activity functions with given ActivityOptions.

This method may be called multiple times to setup Activities with different options.

Type Parameters​

A​

A = UntypedActivities

Parameters​

options​

ActivityProxyOptions<A>

Returns​

ActivityInterfaceFor<A>

a Proxy for which each attribute is a callable Activity function

Example​

import { proxyActivities } from '@temporalio/workflow';
import * as activities from '../activities';

// Setup Activities from module exports
const { httpGet, otherActivity } = proxyActivities<typeof activities>({
  startToCloseTimeout: '30 minutes',
});

// Use activities with default options
const result1 = await httpGet('http://example.com');

// Override options for specific activity calls
const result2 = await httpGet.executeWithOptions({
  staticSummary: 'Fetches data from external API',
  scheduleToCloseTimeout: '5m'
}, ['http://api.example.com']);

const result3 = await otherActivity.executeWithOptions({
  staticSummary: 'Processes the fetched data',
  taskQueue: 'special-task-queue'
}, [data]);

// Setup Activities from an explicit interface (e.g. when defined by another SDK)
interface JavaActivities {
  httpGetFromJava(url: string): Promise<string>
  someOtherJavaActivity(arg1: number, arg2: string): Promise<string>;
}

const {
  httpGetFromJava,
  someOtherJavaActivity
} = proxyActivities<JavaActivities>({
  taskQueue: 'java-worker-taskQueue',
  startToCloseTimeout: '5m',
});

export function execute(): Promise<void> {
  const response = await httpGet("http://example.com");
  // Or with custom options:
  const response2 = await httpGetFromJava.executeWithOptions({
    staticSummary: 'Java HTTP call with timeout override',
    startToCloseTimeout: '2m'
  }, ["http://fast-api.example.com"]);
  // ...
}

proxyLocalActivities()​

proxyLocalActivities<A>(options): LocalActivityInterfaceFor<A>

Configure Local Activity functions with given LocalActivityOptions.

This method may be called multiple times to setup Activities with different options.

Type Parameters​

A​

A = UntypedActivities

Parameters​

options​

LocalActivityProxyOptions<A>

Returns​

LocalActivityInterfaceFor<A>

a Proxy for which each attribute is a callable Activity function

See​

proxyActivities for examples

proxySinks()​

proxySinks<T>(): T

Get a reference to Sinks for exporting data out of the Workflow.

These Sinks must be registered with the Worker in order for this mechanism to work.

Type Parameters​

T​

T extends Sinks

Returns​

T

Example​

import { proxySinks, Sinks } from '@temporalio/workflow';

interface MySinks extends Sinks {
  logger: {
    info(message: string): void;
    error(message: string): void;
  };
}

const { logger } = proxySinks<MyDependencies>();
logger.info('setting up');

export function myWorkflow() {
  return {
    async execute() {
      logger.info("hey ho");
      logger.error("lets go");
    }
  };
}

setCurrentDetails()​

setCurrentDetails(details): void

Parameters​

details​

string

Returns​

void

setDefaultQueryHandler()​

setDefaultQueryHandler(handler): void

Set a query handler function that will handle query calls for non-registered query names.

Queries are dispatched to the default query handler in the order that they were accepted by the server.

If this function is called multiple times for a given query name the last handler will overwrite any previous calls.

Parameters​

handler​

DefaultQueryHandler | undefined

a function that will handle queries for non-registered query names, or undefined to unset the handler.

Returns​

void

setDefaultSignalHandler()​

setDefaultSignalHandler(handler): void

Set a signal handler function that will handle signals calls for non-registered signal names.

Signals are dispatched to the default signal handler in the order that they were accepted by the server.

If this function is called multiple times for a given signal name the last handler will overwrite any previous calls.

Parameters​

handler​

DefaultSignalHandler | undefined

a function that will handle signals for non-registered signal names, or undefined to unset the handler.

Returns​

void

setDefaultUpdateHandler()​

setDefaultUpdateHandler(handler): void

Set a update handler function that will handle updates calls for non-registered update names.

Updates are dispatched to the default update handler in the order that they were accepted by the server.

If this function is called multiple times for a given update name the last handler will overwrite any previous calls.

Parameters​

handler​

DefaultUpdateHandler | undefined

a function that will handle updates for non-registered update names, or undefined to unset the handler.

Returns​

void

setHandler()​

Call Signature​

setHandler<Ret, Args, T>(def, handler, options?): void

Set a handler function for a Workflow update, signal, or query.

If this function is called multiple times for a given update, signal, or query name the last handler will overwrite any previous calls.

Type Parameters​
Ret​

Ret

Args​

Args extends any[]

T​

T extends QueryDefinition<Ret, Args, string>

Parameters​
def​

T

an UpdateDefinition, SignalDefinition, or QueryDefinition as returned by defineUpdate, defineSignal, or defineQuery respectively.

handler​

Handler<Ret, Args, T> | undefined

a compatible handler function for the given definition or undefined to unset the handler.

options?​

QueryHandlerOptions

an optional description of the handler and an optional update validator function.

Returns​

void

Call Signature​

setHandler<Ret, Args, T>(def, handler, options?): void

Set a handler function for a Workflow update, signal, or query.

If this function is called multiple times for a given update, signal, or query name the last handler will overwrite any previous calls.

Type Parameters​
Ret​

Ret

Args​

Args extends any[]

T​

T extends SignalDefinition<Args, string>

Parameters​
def​

T

an UpdateDefinition, SignalDefinition, or QueryDefinition as returned by defineUpdate, defineSignal, or defineQuery respectively.

handler​

Handler<Ret, Args, T> | undefined

a compatible handler function for the given definition or undefined to unset the handler.

options?​

SignalHandlerOptions

an optional description of the handler and an optional update validator function.

Returns​

void

Call Signature​

setHandler<Ret, Args, T>(def, handler, options?): void

Set a handler function for a Workflow update, signal, or query.

If this function is called multiple times for a given update, signal, or query name the last handler will overwrite any previous calls.

Type Parameters​
Ret​

Ret

Args​

Args extends any[]

T​

T extends UpdateDefinition<Ret, Args, string>

Parameters​
def​

T

an UpdateDefinition, SignalDefinition, or QueryDefinition as returned by defineUpdate, defineSignal, or defineQuery respectively.

handler​

Handler<Ret, Args, T> | undefined

a compatible handler function for the given definition or undefined to unset the handler.

options?​

UpdateHandlerOptions<Args>

an optional description of the handler and an optional update validator function.

Returns​

void

setWorkflowOptions()​

setWorkflowOptions<A, RT>(options, fn): void

Can be used to alter workflow functions with certain options specified at definition time.

Prefer defineWorkflowOptions for new code, especially when setting static workflow metadata such as type information.

Type Parameters​

A​

A extends any[]

RT​

RT

Parameters​

options​

WorkflowDefinitionOptionsOrGetter

Options for the workflow defintion, or a function that returns options. If a function is provided, it will be called once just before the workflow function is called for the first time. It is safe to call workflowInfo inside such a function.

fn​

(...args) => Promise<RT>

The workflow function.

Returns​

void

Examples​

For example:

setWorkflowOptions({
  versioningBehavior: 'PINNED',
  failureExceptionTypes: [CustomWorkflowError]
}, myWorkflow);
export async function myWorkflow(): Promise<string> {
  // Workflow code here
  return "hi";
}

To annotate a default or dynamic workflow:

export default async function (): Promise<string> {
  // Workflow code here
  return "hi";
}
setWorkflowOptions({
  versioningBehavior: 'PINNED',
  failureExceptionTypes: [CustomWorkflowError]
}, module.exports.default);

signalWithStartWorkflow()​

signalWithStartWorkflow<WorkflowFn, SignalValue>(requestInput): Promise<ExternalWorkflowHandle>

Experimental

Signal a workflow, starting it first if needed.

Type Parameters​

WorkflowFn​

WorkflowFn extends (...args) => Promise<any> = (...args) => Promise<any>

SignalValue​

SignalValue extends SignalDefinition<any[], string> = SignalDefinition<any[], string>

Parameters​

requestInput​

SignalWithStartWorkflowInput<WorkflowFn, SignalValue>

Returns​

Promise<ExternalWorkflowHandle>

A workflow handle to the started workflow. This API is experimental and subject to change.

sleep()​

sleep(ms, options?): Promise<void>

Asynchronous sleep.

Schedules a timer on the Temporal service.

Parameters​

ms​

Duration

sleep duration - number of milliseconds or ms-formatted string. If given a negative number or 0, value will be set to 1.

options?​

TimerOptions

optional timer options for additional configuration

Returns​

Promise<void>

startChild()​

Call Signature​

startChild<T>(workflowType, options): Promise<ChildWorkflowHandle<T>>

Start a child Workflow execution

  • Returns a client-side handle that implements a child Workflow interface.
  • By default, a child will be scheduled on the same task queue as its parent.

A child Workflow handle supports awaiting completion, signaling and cancellation via CancellationScopes. In order to query the child, use a WorkflowClient from an Activity.

Type Parameters​
T​

T extends Workflow

Parameters​
workflowType​

string

options​

WithWorkflowArgs<T, ChildWorkflowOptions>

Returns​

Promise<ChildWorkflowHandle<T>>

Call Signature​

startChild<T>(workflowFunc, options): Promise<ChildWorkflowHandle<T>>

Start a child Workflow execution

  • Returns a client-side handle that implements a child Workflow interface.
  • Deduces the Workflow type and signature from provided Workflow function.
  • By default, a child will be scheduled on the same task queue as its parent.

A child Workflow handle supports awaiting completion, signaling and cancellation via CancellationScopes. In order to query the child, use a WorkflowClient from an Activity.

Type Parameters​
T​

T extends Workflow

Parameters​
workflowFunc​

T

options​

WithWorkflowArgs<T, ChildWorkflowDefinitionOptions>

Returns​

Promise<ChildWorkflowHandle<T>>

Call Signature​

startChild<T>(workflowType): Promise<ChildWorkflowHandle<T>>

Start a child Workflow execution

Override for Workflows that accept no arguments.

  • Returns a client-side handle that implements a child Workflow interface.
  • The child will be scheduled on the same task queue as its parent.

A child Workflow handle supports awaiting completion, signaling and cancellation via CancellationScopes. In order to query the child, use a WorkflowClient from an Activity.

Type Parameters​
T​

T extends () => Promise<any>

Parameters​
workflowType​

string

Returns​

Promise<ChildWorkflowHandle<T>>

Call Signature​

startChild<T>(workflowFunc): Promise<ChildWorkflowHandle<T>>

Start a child Workflow execution

Override for Workflows that accept no arguments.

  • Returns a client-side handle that implements a child Workflow interface.
  • Deduces the Workflow type and signature from provided Workflow function.
  • The child will be scheduled on the same task queue as its parent.

A child Workflow handle supports awaiting completion, signaling and cancellation via CancellationScopes. In order to query the child, use a WorkflowClient from an Activity.

Type Parameters​
T​

T extends () => Promise<any>

Parameters​
workflowFunc​

T

Returns​

Promise<ChildWorkflowHandle<T>>

upsertMemo()​

upsertMemo(memo, options?): void

Updates this Workflow's Memos by merging the provided memo with existing Memos (as returned by workflowInfo().memo).

New memo is merged by replacing properties of the same name at the first level only. Setting a property to value undefined or null clears that key from the Memo.

For example:

upsertMemo({
  key1: value,
  key3: { subkey1: value }
  key4: value,
});
upsertMemo({
  key2: value
  key3: { subkey2: value }
  key4: undefined,
});

would result in the Workflow having these Memo:

{
  key1: value,
  key2: value,
  key3: { subkey2: value }  // Note this object was completely replaced
  // Note that key4 was completely removed
}

Parameters​

memo​

Record<string, unknown>

The Record to merge.

options?​

EventGroupsOptions

Returns​

void

upsertSearchAttributes()​

upsertSearchAttributes(searchAttributes, options?): void

Updates this Workflow's Search Attributes by merging the provided searchAttributes with the existing Search Attributes, workflowInfo().searchAttributes.

Search attributes can be upserted using either SearchAttributes (deprecated) or SearchAttributeUpdatePair[] (preferred)

Upserting a workflow's search attributes using SearchAttributeUpdatePair[]:

const intKey = defineSearchKey('CustomIntField', 'INT');
const boolKey = defineSearchKey('CustomBoolField', 'BOOL');
const keywordListKey = defineSearchKey('CustomKeywordField', 'KEYWORD_LIST');

upsertSearchAttributes([
 defineSearchAttribute(intKey, 1),
 defineSearchAttribute(boolKey, true)
]);
upsertSearchAttributes([
 defineSearchAttribute(intKey, 42),
 defineSearchAttribute(keywordListKey, ['durable code', 'is great'])
]);

Would result in the Workflow having these Search Attributes:

{
  CustomIntField: [42],
  CustomBoolField: [true],
  CustomKeywordField: ['durable code', 'is great']
}

Parameters​

searchAttributes​

SearchAttributes | SearchAttributeUpdatePair[]

The Record to merge. If using SearchAttributeUpdatePair[] (preferred), set a value to null to remove the search attribute. If using SearchAttributes (deprecated), set a value to undefined or an empty list to remove the search attribute.

options?​

EventGroupsOptions

Returns​

void

uuid4()​

uuid4(): string

Generate an RFC compliant V4 uuid. Uses the workflow's deterministic PRNG making it safe for use within a workflow. This function is cryptographically insecure. See the stackoverflow discussion.

Returns​

string

workflowInfo()​

workflowInfo(): WorkflowInfo

Get information about the current Workflow.

WARNING: This function returns a frozen copy of WorkflowInfo, at the point where this method has been called. Changes happening at later point in workflow execution will not be reflected in the returned object.

For this reason, we recommend calling workflowInfo() on every access to WorkflowInfo's fields, rather than caching the WorkflowInfo object (or part of it) in a local variable. For example:

// GOOD
function myWorkflow() {
  doSomething(workflowInfo().searchAttributes)
  ...
  doSomethingElse(workflowInfo().searchAttributes)
}

vs

// BAD
function myWorkflow() {
  const attributes = workflowInfo().searchAttributes
  doSomething(attributes)
  ...
  doSomethingElse(attributes)
}

Returns​

WorkflowInfo

References​

ActivityCancellationType​

Re-exports ActivityCancellationType

ActivityFailure​

Re-exports ActivityFailure

ActivityFunction​

Re-exports ActivityFunction

ActivityInterface​

Re-exports ActivityInterface

ActivityTypeInfoMap​

Re-exports ActivityTypeInfoMap

ApplicationFailure​

Re-exports ApplicationFailure

AutoUpgradeVersioningOverride​

Re-exports AutoUpgradeVersioningOverride

BaseWorkflowHandle​

Re-exports BaseWorkflowHandle

BaseWorkflowOptions​

Re-exports BaseWorkflowOptions

CancelledFailure​

Re-exports CancelledFailure

ChildWorkflowFailure​

Re-exports ChildWorkflowFailure

CommonWorkflowOptions​

Re-exports CommonWorkflowOptions

CompleteAsyncError​

Re-exports CompleteAsyncError

decodeWorkflowIdConflictPolicy​

Re-exports decodeWorkflowIdConflictPolicy

decodeWorkflowIdReusePolicy​

Re-exports decodeWorkflowIdReusePolicy

defaultPayloadConverter​

Re-exports defaultPayloadConverter

encodeWorkflowIdConflictPolicy​

Re-exports encodeWorkflowIdConflictPolicy

encodeWorkflowIdReusePolicy​

Re-exports encodeWorkflowIdReusePolicy

ExternalStorageDriverError​

Re-exports ExternalStorageDriverError

ExternalStorageError​

Re-exports ExternalStorageError

ExternalStorageNotConfiguredError​

Re-exports ExternalStorageNotConfiguredError

ExternalStorageReferenceError​

Re-exports ExternalStorageReferenceError

ExternalStorageUnregisteredDriverError​

Re-exports ExternalStorageUnregisteredDriverError

extractWorkflowType​

Re-exports extractWorkflowType

extractWorkflowTypeAndConfig​

Re-exports extractWorkflowTypeAndConfig

Headers​

Re-exports Headers

IllegalStateError​

Re-exports IllegalStateError

InvalidVersioningOverrideError​

Re-exports InvalidVersioningOverrideError

NamespaceNotFoundError​

Re-exports NamespaceNotFoundError

Next​

Re-exports Next

OneTimeVersioningOverride​

Re-exports OneTimeVersioningOverride

Payload​

Re-exports Payload

PayloadConverter​

Re-exports PayloadConverter

PayloadConverterError​

Re-exports PayloadConverterError

PinnedVersioningOverride​

Re-exports PinnedVersioningOverride

QueryDefinition​

Re-exports QueryDefinition

RetryPolicy​

Re-exports RetryPolicy

rootCause​

Re-exports rootCause

SearchAttributes​

Re-exports SearchAttributes

SearchAttributeValue​

Re-exports SearchAttributeValue

ServerFailure​

Re-exports ServerFailure

SignalDefinition​

Re-exports SignalDefinition

TemporalFailure​

Re-exports TemporalFailure

TerminatedFailure​

Re-exports TerminatedFailure

TimeoutFailure​

Re-exports TimeoutFailure

UntypedActivities​

Re-exports UntypedActivities

ValueError​

Re-exports ValueError

VersioningOverride​

Re-exports VersioningOverride

WithWorkflowArgs​

Re-exports WithWorkflowArgs

WorkerDeploymentVersion​

Re-exports WorkerDeploymentVersion

Workflow​

Re-exports Workflow

WorkflowDurationOptions​

Re-exports WorkflowDurationOptions

WorkflowIdConflictPolicy​

Re-exports WorkflowIdConflictPolicy

WorkflowIdReusePolicy​

Re-exports WorkflowIdReusePolicy

WorkflowNotFoundError​

Re-exports WorkflowNotFoundError

WorkflowQueryOptions​

Re-exports WorkflowQueryOptions

WorkflowQueryType​

Re-exports WorkflowQueryType

WorkflowResultType​

Re-exports WorkflowResultType

WorkflowReturnType​

Re-exports WorkflowReturnType

WorkflowSignalOptions​

Re-exports WorkflowSignalOptions

WorkflowSignalType​

Re-exports WorkflowSignalType

WorkflowTypeOptions​

Re-exports WorkflowTypeOptions