flowgraph/tasks/host-reactive.md

id, name, status, depends_on, scope, risk, impact, level

id	name	status	depends_on	scope	risk	impact	level
host/reactive	Implement ReactiveHostConfig — render ujsx template to reactive execution engine	completed	component/operation component/sequential component/parallel component/conditional component/map reactive/workflow-root reactive/node-status schema/edge-attrs	broad	critical	phase	implementation

Description

Implement the ReactiveHostConfig that renders a ujsx workflow template into a reactive execution engine with signal-backed NodeStatus tracking, computed preconditions, and failure propagation. This is the runtime execution rendering path.

Acceptance Criteria

• src/host/reactive.ts exports ReactiveHostConfig implementing ujsx HostConfig<WorkflowTag, WorkflowNode, ReactiveContext>
• WorkflowNode: { key, type, status: Signal<NodeStatus>, preconditions: Computed<boolean>, blockedByFailure: Computed<boolean>, operationId?, output?: Signal<unknown>, children: WorkflowNode[] }
• ReactiveContext: { operationRegistry, nodes: Map, statusSignals: Map, preconditions: Map, blockedByFailure: Map, resultProjection: EventLogProjection, parentMap, siblingMap, results: Map }
• createInstance("operation", props, ctx): creates WorkflowNode with status signal from ReactiveContext, registers in context maps
• createInstance for structural containers: creates WorkflowNode tracking children but no graph node
• Prerequisite computation: Sequential child → previous sibling completed/skipped; Parallel child → parent's preconditions met; Conditional child → condition evaluates to true
• Status propagation: effects on preconditions and blockedByFailure drive state transitions
• removeChild: removes parent-child dependency, preconditions/blockedByFailure auto-re-evaluate (reactive)
• removeChildFromHost: disposes node's signal references from context maps
• Re-exported from src/host/index.ts
• Integration tests: render template → assert signal initial states, transition predecessor → assert dependent precondition updates, failure propagation, Conditional as error boundary

References

• docs/architecture/host-configs.md — ReactiveHostConfig full specification, WorkflowNode, ReactiveContext
• docs/architecture/reactive-execution.md — signal-backed execution model, precondition computation, status propagation
• docs/architecture/workflow-templates.md — template→reactive execution conversion

Notes

To be filled by implementation agent

Summary

To be filled on completion