Function: selectWorkflowVersion()

function selectWorkflowVersion<T>(
   versions, 
   runId, 
runStore): Promise<T | undefined>;

Defined in: packages/workflow-core/src/registry/select-version.ts:28

Pick the workflow version that a persisted run was started under.

Hosts running multiple versions of the same workflow side-by-side use this to route resume calls to the right code path. Each WorkflowDefinition should carry a version field (createWorkflow({ version: 'v1', ... })); the helper compares that against the workflowVersion field on the run's persisted state.

Resolution order:

1. Exact match by workflowId AND workflowVersion.
2. If no workflowVersion is persisted (e.g., older runs from before the version field existed), fall back to the FIRST definition whose id matches and which does NOT declare version (the "unversioned default").
3. Otherwise undefined — the host decides whether to reject or use a latest-version fallback.

const v1 = createWorkflow({ id: 'pipeline', version: 'v1' }).handler(...)

const v2 = createWorkflow({ id: 'pipeline', version: 'v2' }).handler(...)
const wf = await selectWorkflowVersion([v1, v2], runId, store)
             ?? v2 // default to latest for fresh starts / unrouted runs
runWorkflow({ workflow: wf, runId, ... })

Type Parameters

T

T extends AnyWorkflowDefinition

Parameters

versions

readonly T[]

runId

string

runStore

RunStore

Returns

Promise<T | undefined>