Temporal Nexus available for multiple SDKs
Temporal Nexus quickstarts are available for Go, Java, .NET, Python, and TypeScript SDKs. Nexus is used to connect Temporal Applications within and across Namespaces.
nexus operations
14 notes, read out of this brain and free to use. Each one was extracted from a source and is re-checked against its exam.
NexusOperationScheduled event indicates workflow scheduled a Nexus Operation
The NexusOperationScheduled event type indicates that a Nexus Operation was scheduled by a caller Workflow. The caller's Nexus Machinery will attempt to start the Nexus Operation. This event contains Nexus Operation input and the Operation request ID.
NexusOperationScheduled event fields
NexusOperationScheduled event fields: endpoint (Endpoint name, must exist in the endpoint registry), service (Service name), operation (Operation name), input (Input for the operation; server converts to Nexus request content and headers; on handler side if backed by Temporal, content is transformed back to original Payload), schedule_to_close_timeout (Schedule-to-close timeout indicating how long caller is willing to wait for operation completion; calls are retried internally by server), nexus_header (Header to attach to Nexus request; these headers are not same as Temporal headers on internal activities and child Workflows, transmitted to external Nexus operations), workflow_task_completed_event_id (ID of WorkflowTaskCompleted event that corresponding ScheduleNexusOperation command was reported with), request_id (unique ID generated by History Service upon creation; transmitted with all Nexus StartOperation requests; used as idempotency key), endpoint_id (Endpoint ID as resolved in endpoint registry at time event was generated; stored on event and used internally by server in case endpoint is renamed).
NexusOperationStarted event indicates asynchronous Nexus Operation execution started
The NexusOperationStarted event type indicates that a Nexus Operation Execution was started. This event is added to the caller's Event History for Asynchronous Nexus Operations (for example those backed by a Workflow). The event is not added to the caller's Event History for Synchronous Nexus Operations, since they transition directly to NexusOperationCompleted or another final state such as NexusOperationFailed when the response is provided synchronously by the Nexus handler.
NexusOperationStarted event fields
NexusOperationStarted event fields: scheduled_event_id (ID of NexusOperationScheduled event this task corresponds to), operation_token (operation token returned by Nexus handler in response to StartOperation request; used when canceling the operation), request_id (request ID allocated at schedule time).
NexusOperationCompleted event indicates successful Nexus Operation
The NexusOperationCompleted event type indicates that a Nexus Operation has completed successfully. The caller's Event History records the result of a successful Nexus Operation with this event for both synchronous and asynchronous Nexus Operations. This event type contains Nexus Operation results.
NexusOperationCompleted event fields
NexusOperationCompleted event fields: scheduled_event_id (ID of NexusOperationScheduled event; uniquely identifies this operation), result (serialized result of the Nexus operation; the response of the Nexus handler; delivered either via completion callback or as response to synchronous operation), request_id (request ID allocated at schedule time).
NexusOperationFailed event indicates Nexus Operation failure
The NexusOperationFailed event type indicates that a Nexus Operation has failed. The caller's Event History records a failed Nexus Operation with this event for both synchronous and asynchronous Nexus Operations. Failures can occur when a Nexus Handler responds synchronously with a non-retryable error or when a Workflow backing an Operation fails (resulting in WorkflowExecutionFailed event). When an SDK client picks up a Nexus Operation, the Nexus handler asynchronously starts an underlying Workflow, which can subsequently result in WorkflowExecutionFailed. This event contains Nexus Operation failure details.
NexusOperationTimedOut event indicates Nexus Operation timeout
The NexusOperationTimedOut event type indicates that a Nexus Operation has timed out according to the Temporal Server due to Schedule-to-Close Timeout.
NexusOperationTimedOut event fields
NexusOperationTimedOut event fields: scheduled_event_id (ID of NexusOperationScheduled event; uniquely identifies this operation), failure (Failure details; a NexusOperationFailureInfo wrapping a CanceledFailureInfo), request_id (request ID allocated at schedule time).
NexusOperationCancelRequested event indicates workflow requested Nexus Operation cancellation
The NexusOperationCancelRequested event type indicates that the Workflow that scheduled a Nexus Operation requested to cancel it.
NexusOperationCancelRequested event fields
NexusOperationCancelRequested event fields: scheduled_event_id (ID of NexusOperationScheduled event this cancel request corresponds to), workflow_task_completed_event_id (WorkflowTaskCompleted event that the corresponding RequestCancelNexusOperation command was reported with).
NexusOperationCanceled event indicates Nexus Operation resolved as canceled
The NexusOperationCanceled event type indicates that a Nexus Operation has resolved as canceled.
NexusOperationCanceled event fields
NexusOperationCanceled event fields: scheduled_event_id (ID of NexusOperationScheduled event; uniquely identifies this operation), failure (Cancellation details), request_id (request ID allocated at schedule time).