DurableOrchestrationContext class

Reference

Package:: durable-functions

Parameter data for orchestration bindings that can be used to schedule function-based activities.

Constructors

DurableOrchestrationContext(HistoryEvent[], string, Date, boolean, string | undefined, string | undefined, string | undefined, number | undefined, ReplaySchema, unknown, TaskOrchestrationExecutor)

Properties

currentUtcDateTime	Gets the current date/time in a way that is safe for use by orchestrator functions. This date/time value is derived from the orchestration history. It always returns the same value at specific points in the orchestrator function code, making it deterministic and safe for replay.
customStatus
instanceId	The ID of the current orchestration instance. The instance ID is generated and fixed when the orchestrator function is scheduled. It can be either auto-generated, in which case it is formatted as a GUID, or it can be user-specified with any format.
isReplaying	Gets a value indicating whether the orchestrator function is currently replaying itself. This property is useful when there is logic that needs to run only when the orchestrator function is not replaying. For example, certain types of application logging may become too noisy when duplicated as part of orchestrator function replay. The orchestrator code could check to see whether the function is being replayed and then issue the log statements when this value is `false`.
parentInstanceId	The ID of the parent orchestration of the current sub-orchestration instance. The value will be available only in sub-orchestrations. The parent instance ID is generated and fixed when the parent orchestrator function is scheduled. It can be either auto-generated, in which case it is formatted as a GUID, or it can be user-specified with any format.
Task	Just an entry point to reference the methods in [[ITaskMethods]]. Methods to handle collections of pending actions represented by [[Task]] instances. For use in parallelization operations.

Methods

callActivity(string, unknown)	Schedules an activity function named `name` for execution.
callActivityWithRetry(string, RetryOptions, unknown)	Schedules an activity function named `name` for execution with retry options.
callEntity(EntityId, string, unknown)	Calls an operation on an entity, passing an argument, and waits for it to complete.
callHttp(string, string, string \| object, [key: string]: string, TokenSource, boolean)	Schedules a durable HTTP call to the specified endpoint.
callSubOrchestrator(string, unknown, string)	Schedules an orchestration function named `name` for execution.
callSubOrchestratorWithRetry(string, RetryOptions, unknown, string)	Schedules an orchestrator function named `name` for execution with retry options.
continueAsNew(unknown)	Restarts the orchestration by clearing its history.
createTimer(Date)	Creates a durable timer that expires at a specified time. All durable timers created using this method must either expire or be cancelled using [[TimerTask]].[[cancel]] before the orchestrator function completes. Otherwise, the underlying framework will keep the instance alive until the timer expires. Timers currently cannot be scheduled further than 7 days into the future.
getInput<T>()	Gets the input of the current orchestrator function as a deserialized value.
newGuid(string)	Creates a new GUID that is safe for replay within an orchestration or operation. The default implementation of this method creates a name-based UUID using the algorithm from RFC 4122 §4.3. The name input used to generate this value is a combination of the orchestration instance ID and an internally managed sequence number.
setCustomStatus(unknown)	Sets the JSON-serializable status of the current orchestrator function. The `customStatusObject` value is serialized to JSON and will be made available to the orchestration status query APIs. The serialized JSON value must not exceed 16 KB of UTF-16 encoded text. The serialized `customStatusObject` value will be made available to the aforementioned APIs after the next `yield` or `return` statement.
waitForExternalEvent(string)	Waits asynchronously for an event to be raised with the name `name` and returns the event data. External clients can raise events to a waiting orchestration instance using [[raiseEvent]].

Constructor Details

DurableOrchestrationContext(HistoryEvent[], string, Date, boolean, string | undefined, string | undefined, string | undefined, number | undefined, ReplaySchema, unknown, TaskOrchestrationExecutor)

new DurableOrchestrationContext(state: HistoryEvent[], instanceId: string, currentUtcDateTime: Date, isReplaying: boolean, parentInstanceId: string | undefined, longRunningTimerIntervalDuration: string | undefined, maximumShortTimerDuration: string | undefined, defaultHttpAsyncRequestSleepTimeMillseconds: number | undefined, schemaVersion: ReplaySchema, input: unknown, taskOrchestratorExecutor: TaskOrchestrationExecutor)

Parameters

state: HistoryEvent[]

instanceId: string

currentUtcDateTime: Date

isReplaying: boolean

parentInstanceId: string | undefined

longRunningTimerIntervalDuration: string | undefined

maximumShortTimerDuration: string | undefined

defaultHttpAsyncRequestSleepTimeMillseconds: number | undefined

schemaVersion: ReplaySchema

input: unknown

taskOrchestratorExecutor: TaskOrchestrationExecutor

Property Details

currentUtcDateTime

Gets the current date/time in a way that is safe for use by orchestrator functions. This date/time value is derived from the orchestration history. It always returns the same value at specific points in the orchestrator function code, making it deterministic and safe for replay.

currentUtcDateTime: Date

Property Value

Date

customStatus

customStatus: unknown

Property Value

unknown

instanceId

The ID of the current orchestration instance. The instance ID is generated and fixed when the orchestrator function is scheduled. It can be either auto-generated, in which case it is formatted as a GUID, or it can be user-specified with any format.

instanceId: string

Property Value

string

isReplaying

Gets a value indicating whether the orchestrator function is currently replaying itself. This property is useful when there is logic that needs to run only when the orchestrator function is not replaying. For example, certain types of application logging may become too noisy when duplicated as part of orchestrator function replay. The orchestrator code could check to see whether the function is being replayed and then issue the log statements when this value is false.

isReplaying: boolean

Property Value

boolean

parentInstanceId

The ID of the parent orchestration of the current sub-orchestration instance. The value will be available only in sub-orchestrations. The parent instance ID is generated and fixed when the parent orchestrator function is scheduled. It can be either auto-generated, in which case it is formatted as a GUID, or it can be user-specified with any format.

parentInstanceId: string | undefined

Property Value

string | undefined

Task

Just an entry point to reference the methods in [[ITaskMethods]]. Methods to handle collections of pending actions represented by [[Task]] instances. For use in parallelization operations.

Task: { all: (tasks: Task[]) => Task, any: (tasks: Task[]) => Task }

Property Value

{ all: (tasks: Task[]) => Task, any: (tasks: Task[]) => Task }

Method Details

callActivity(string, unknown)

Schedules an activity function named name for execution.

function callActivity(name: string, input?: unknown): Task

Parameters

name: string

The name of the activity function to call.

input: unknown

The JSON-serializable input to pass to the activity function.

Returns

Task

A Durable Task that completes when the called activity function completes or fails.

callActivityWithRetry(string, RetryOptions, unknown)

Schedules an activity function named name for execution with retry options.

function callActivityWithRetry(name: string, retryOptions: RetryOptions, input?: unknown): Task

Parameters

name: string

The name of the activity function to call.

retryOptions: RetryOptions

The retry options for the activity function.

input: unknown

The JSON-serializable input to pass to the activity function.

Returns

Task

callEntity(EntityId, string, unknown)

Calls an operation on an entity, passing an argument, and waits for it to complete.

function callEntity(entityId: EntityId, operationName: string, operationInput?: unknown): Task

Parameters

entityId: EntityId

The target entity.

operationName: string

The name of the operation.

operationInput: unknown

The input for the operation.

Returns

Task

callHttp(string, string, string | object, [key: string]: string, TokenSource, boolean)

Schedules a durable HTTP call to the specified endpoint.

function callHttp(method: string, uri: string, content?: string | object, headers?: [key: string]: string, tokenSource?: TokenSource, asynchronousPatternEnabled?: boolean): Task

Parameters

method: string

uri: string

content: string | object

headers: [key: string]: string

tokenSource: TokenSource

asynchronousPatternEnabled: boolean

Returns

Task

callSubOrchestrator(string, unknown, string)

Schedules an orchestration function named name for execution.

function callSubOrchestrator(name: string, input?: unknown, instanceId?: string): Task

Parameters

name: string

The name of the orchestrator function to call.

input: unknown

The JSON-serializable input to pass to the orchestrator function.

instanceId: string

A unique ID to use for the sub-orchestration instance. If instanceId is not specified, the extension will generate an id in the format <calling orchestrator instance ID>:<#>

Returns

Task

callSubOrchestratorWithRetry(string, RetryOptions, unknown, string)

Schedules an orchestrator function named name for execution with retry options.

function callSubOrchestratorWithRetry(name: string, retryOptions: RetryOptions, input?: unknown, instanceId?: string): Task

Parameters

name: string

The name of the orchestrator function to call.

retryOptions: RetryOptions

The retry options for the orchestrator function.

input: unknown

The JSON-serializable input to pass to the orchestrator function.

instanceId: string

A unique ID to use for the sub-orchestration instance.

Returns

Task

continueAsNew(unknown)

Restarts the orchestration by clearing its history.

function continueAsNew(input: unknown)

Parameters

input: unknown

createTimer(Date)

Creates a durable timer that expires at a specified time. All durable timers created using this method must either expire or be cancelled using [[TimerTask]].[[cancel]] before the orchestrator function completes. Otherwise, the underlying framework will keep the instance alive until the timer expires.

Timers currently cannot be scheduled further than 7 days into the future.

function createTimer(fireAt: Date): TimerTask

Parameters

fireAt: Date

The time at which the timer should expire.

Returns

TimerTask

A TimerTask that completes when the durable timer expires.

getInput<T>()

Gets the input of the current orchestrator function as a deserialized value.

function getInput<T>(): T

Returns

newGuid(string)

Creates a new GUID that is safe for replay within an orchestration or operation. The default implementation of this method creates a name-based UUID using the algorithm from RFC 4122 §4.3. The name input used to generate this value is a combination of the orchestration instance ID and an internally managed sequence number.

function newGuid(instanceId: string): string

Parameters

instanceId: string

Returns

string

setCustomStatus(unknown)

Sets the JSON-serializable status of the current orchestrator function. The customStatusObject value is serialized to JSON and will be made available to the orchestration status query APIs. The serialized JSON value must not exceed 16 KB of UTF-16 encoded text.

The serialized customStatusObject value will be made available to the aforementioned APIs after the next yield or return statement.

function setCustomStatus(customStatusObject: unknown)

Parameters

customStatusObject: unknown

The JSON-serializable value to use as the orchestrator function's custom status.

waitForExternalEvent(string)

Waits asynchronously for an event to be raised with the name name and returns the event data. External clients can raise events to a waiting orchestration instance using [[raiseEvent]].

function waitForExternalEvent(name: string): Task

Parameters

name: string

Returns

Task