Namespace: 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.
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
Enumerations
Classes
- CancellationScope
- ContinueAsNew
- DeterminismViolationError
- LocalActivityDoBackoff
- Trigger
- WorkflowError
Interfaces
- ActivateInput
- ActivityInput
- CancellationScopeOptions
- ChildWorkflowHandle
- ChildWorkflowOptions
- ConcludeActivationInput
- ContinueAsNewInput
- ContinueAsNewOptions
- DisposeInput
- EnhancedStackTrace
- ExternalWorkflowHandle
- FileLocation
- FileSlice
- LocalActivityInput
- LoggerSinks
- ParentWorkflowInfo
- QueryInput
- SDKInfo
- SignalInput
- SignalWorkflowInput
- SinkCall
- StackTrace
- StartChildWorkflowExecutionInput
- TimerInput
- UnsafeWorkflowInfo
- UpdateInput
- WorkflowExecuteInput
- WorkflowInboundCallsInterceptor
- WorkflowInfo
- WorkflowInterceptors
- WorkflowInternalsInterceptor
- WorkflowOutboundCallsInterceptor
References
ActivityCancellationType
Re-exports ActivityCancellationType
ActivityFailure
Re-exports ActivityFailure
ActivityFunction
Re-exports ActivityFunction
ActivityInterface
Re-exports ActivityInterface
ActivityOptions
Re-exports ActivityOptions
ApplicationFailure
Re-exports ApplicationFailure
BaseWorkflowHandle
Re-exports BaseWorkflowHandle
BaseWorkflowOptions
Re-exports BaseWorkflowOptions
CancelledFailure
Re-exports CancelledFailure
ChildWorkflowFailure
Re-exports ChildWorkflowFailure
CommonWorkflowOptions
Re-exports CommonWorkflowOptions
Headers
Re-exports Headers
IllegalStateError
Re-exports IllegalStateError
NamespaceNotFoundError
Re-exports NamespaceNotFoundError
Next
Re-exports Next
Payload
Re-exports Payload
PayloadConverter
Re-exports PayloadConverter
PayloadConverterError
Re-exports PayloadConverterError
QueryDefinition
Re-exports QueryDefinition
RetryPolicy
Re-exports RetryPolicy
SearchAttributeValue
Re-exports SearchAttributeValue
SearchAttributes
Re-exports SearchAttributes
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
WithWorkflowArgs
Re-exports WithWorkflowArgs
Workflow
Re-exports Workflow
WorkflowDurationOptions
Re-exports WorkflowDurationOptions
WorkflowExecutionAlreadyStartedError
Re-exports WorkflowExecutionAlreadyStartedError
WorkflowIdReusePolicy
Re-exports WorkflowIdReusePolicy
WorkflowNotFoundError
Re-exports WorkflowNotFoundError
WorkflowQueryType
Re-exports WorkflowQueryType
WorkflowResultType
Re-exports WorkflowResultType
WorkflowReturnType
Re-exports WorkflowReturnType
WorkflowSignalType
Re-exports WorkflowSignalType
defaultPayloadConverter
Re-exports defaultPayloadConverter
extractWorkflowType
Re-exports extractWorkflowType
rootCause
Re-exports rootCause
Type Aliases
ActivityInterfaceFor
Ƭ ActivityInterfaceFor<T
>: { [K in keyof T]: T[K] extends ActivityFunction ? T[K] : typeof NotAnActivityMethod }
Type helper that takes a type T
and transforms attributes that are not ActivityFunction to
NotAnActivityMethod.
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)
Type parameters
Name |
---|
T |
ConcludeActivationOutput
Ƭ ConcludeActivationOutput: ConcludeActivationInput
Output for WorkflowInternalsInterceptor.concludeActivation
ContinueAsNewInputOptions
Ƭ ContinueAsNewInputOptions: ContinueAsNewOptions
& Required
<Pick
<ContinueAsNewOptions
, "workflowType"
>>
Same as ContinueAsNewOptions but workflowType must be defined
GetLogAttributesInput
Ƭ GetLogAttributesInput: Record
<string
, unknown
>
Input for WorkflowOutboundCallsInterceptor.getLogAttributes
Sink
Ƭ Sink: Record
<string
, SinkFunction
>
A mapping of name to function, defines a single sink (e.g. logger)
SinkFunction
Ƭ SinkFunction: (...args
: any
[]) => 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).
Type declaration
▸ (...args
): void
Parameters
Name | Type |
---|---|
...args | any [] |
Returns
void
Sinks
Ƭ Sinks: Record
<string
, Sink
>
Workflow Sink are a mapping of name to Sink
WorkflowInterceptorsFactory
Ƭ WorkflowInterceptorsFactory: () => WorkflowInterceptors
A function that returns WorkflowInterceptors and takes no arguments.
Workflow interceptor modules should export an interceptors
function of this type.
Example
export function interceptors(): WorkflowInterceptors {
return {
inbound: [], // Populate with list of interceptor implementations
outbound: [], // Populate with list of interceptor implementations
internals: [], // Populate with list of interceptor implementations
};
}
Type declaration
▸ (): WorkflowInterceptors
Returns
Variables
AsyncLocalStorage
• Const
AsyncLocalStorage: <T>() => ALS
<T
>
Type declaration
• <T
>(): ALS
<T
>
Type parameters
Name |
---|
T |
Returns
ALS
<T
>
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
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.
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.
stackTraceQuery
• Const
stackTraceQuery: QueryDefinition
<string
, [], string
>
workflowMetadataQuery
• Const
workflowMetadataQuery: QueryDefinition
<IWorkflowMetadata
, [], string
>
Functions
addDefaultWorkflowOptions
▸ addDefaultWorkflowOptions<T
>(opts
): ChildWorkflowOptionsWithDefaults
Adds default values to workflowId
and workflowIdReusePolicy
to given workflow options.
Type parameters
Name | Type |
---|---|
T | extends Workflow |
Parameters
Name | Type |
---|---|
opts | WithWorkflowArgs <T , ChildWorkflowOptions > |
Returns
ChildWorkflowOptionsWithDefaults
condition
▸ condition(fn
, timeout
): Promise
<boolean
>
Returns a Promise that resolves when fn
evaluates to true
or timeout
expires.
Parameters
Name | Type | Description |
---|---|---|
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
▸ condition(fn
): Promise
<void
>
Returns a Promise that resolves when fn
evaluates to true
.
Parameters
Name | Type |
---|---|
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
Name | Type |
---|---|
F | extends Workflow |
Parameters
Name | Type |
---|---|
...args | Parameters <F > |
Returns
Promise
<never
>
Example
import { continueAsNew } from '@temporalio/workflow';
export async function myWorkflow(n: number): Promise<void> {
// ... Workflow logic
await continueAsNew<typeof myWorkflow>(n + 1);
}
defineQuery
▸ defineQuery<Ret
, Args
, Name
>(name
): QueryDefinition
<Ret
, Args
, Name
>
Define a query method for a Workflow.
Definitions are used to register handler in the Workflow via setHandler and to query Workflows using a WorkflowHandle. Definitions can be reused in multiple Workflows.
Type parameters
Name | Type |
---|---|
Ret | Ret |
Args | extends any [] = [] |
Name | extends string = string |
Parameters
Name | Type |
---|---|
name | Name |
Returns
QueryDefinition
<Ret
, Args
, Name
>
defineSignal
▸ defineSignal<Args
, Name
>(name
): SignalDefinition
<Args
, Name
>
Define a signal method for a Workflow.
Definitions are used to register handler in the Workflow via setHandler and to signal Workflows using a WorkflowHandle, ChildWorkflowHandle or ExternalWorkflowHandle. Definitions can be reused in multiple Workflows.
Type parameters
Name | Type |
---|---|
Args | extends any [] = [] |
Name | extends string = string |
Parameters
Name | Type |
---|---|
name | Name |
Returns
SignalDefinition
<Args
, Name
>
defineUpdate
▸ defineUpdate<Ret
, Args
, Name
>(name
): UpdateDefinition
<Ret
, Args
, Name
>
Define an update method for a Workflow.
Definitions are used to register handler in the Workflow via setHandler and to update Workflows using a WorkflowHandle, ChildWorkflowHandle or ExternalWorkflowHandle. Definitions can be reused in multiple Workflows.
Type parameters
Name | Type |
---|---|
Ret | Ret |
Args | extends any [] = [] |
Name | extends string = string |
Parameters
Name | Type |
---|---|
name | Name |
Returns
UpdateDefinition
<Ret
, Args
, Name
>
deprecatePatch
▸ deprecatePatch(patchId
): 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
Name | Type | Description |
---|---|---|
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. |
Returns
void
executeChild
▸ 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
Name | Type |
---|---|
T | extends Workflow |
Parameters
Name | Type |
---|---|
workflowType | string |
options | WithWorkflowArgs <T , ChildWorkflowOptions > |
Returns
Promise
<WorkflowResultType
<T
>>
The result of the child Workflow.
▸ 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
Name | Type |
---|---|
T | extends Workflow |
Parameters
Name | Type |
---|---|
workflowFunc | T |
options | WithWorkflowArgs <T , ChildWorkflowOptions > |
Returns
Promise
<WorkflowResultType
<T
>>
The result of the child Workflow.
▸ 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
Name | Type |
---|---|
T | extends () => WorkflowReturnType |
Parameters
Name | Type |
---|---|
workflowType | string |
Returns
Promise
<WorkflowResultType
<T
>>
The result of the child Workflow.
▸ 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
Name | Type |
---|---|
T | extends () => WorkflowReturnType |
Parameters
Name | Type |
---|---|
workflowFunc | T |
Returns
Promise
<WorkflowResultType
<T
>>
The result of the child Workflow.
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
Name | Type |
---|---|
workflowId | string |
runId? | string |
Returns
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
Name | Type |
---|---|
err | unknown |
Returns
boolean