Struct Runner 

pub struct Runner { /* private fields */ }

DAG workflow runner with event sourcing

Consumes AnalyzedWorkflow directly from the analyzer. Bridge conversions (lower_action, lower_output) happen at the TaskExecutor boundary only.

Implementations

impl Runner

pub fn new(workflow: AnalyzedWorkflow) -> Result<Self, NikaError>

pub fn with_event_log( workflow: AnalyzedWorkflow, event_log: EventLog, ) -> Result<Self, NikaError>

Create a Runner with a custom EventLog (for TUI integration)

Use EventLog::new_with_broadcast() to create an EventLog that sends events to TUI in real-time.

Errors

Returns NikaError::ValidationError if DAG construction fails (e.g. the workflow contains cycles or invalid dependencies).

pub fn quiet(self) -> Self

Enable quiet mode to suppress console output (for TUI mode)

When quiet is true, Runner will not print to stdout/stderr. All events are still emitted to the EventLog for TUI display.

pub fn with_detail_level(self, detail: DetailLevel) -> Self

Set the CLI detail level for event rendering.

Automatically selects Live (animated) or Classic (append-only) renderer based on TTY detection and detail level.

pub fn with_classic_renderer(self, detail: DetailLevel) -> Self

Force the classic (append-only) renderer regardless of TTY.

pub fn datastore(&self) -> &RunContext

Get a reference to the run context (task results store).

Available after run() completes to collect task outputs for -o/--output.

pub fn with_initial_context(self, key: &str, context: Value) -> Self

Inject initial context into the datastore

Used by nika_run to pass parent context to child workflows. The context is stored as a successful task result under the given key, making it accessible via with: alias: <key>.result in the child workflow.

Example

// In parent workflow via nika_run:
// context: { "entity": "qr-code", "locale": "fr-FR" }

// Child workflow can access via:
// with:
//   parent: __parent_context__.result

pub fn with_permission_mode(self, mode: PermissionMode) -> Self

Set the permission mode for file tools (nika:write, nika:edit, etc.)

By default, PermissionMode::Plan is used (deny writes, emit permission request). For nika run, use AcceptAll since the user explicitly chose to run.

pub fn with_cancel_token(self, token: CancellationToken) -> Self

Set a custom cancellation token

This allows external control of workflow cancellation. The TUI can hold a clone of the token and call cancel() on it. Also propagated to TaskExecutor so MCP invoke operations abort promptly instead of waiting for INVOKE_TASK_DEADLINE.

pub fn cancel_token(&self) -> CancellationToken

Get a clone of the cancellation token

The TUI can use this to abort the workflow by calling cancel().

pub fn is_cancelled(&self) -> bool

Check if the workflow has been cancelled

pub fn pause(&self)

Pause workflow execution

When paused, the runner will complete current tasks but won’t start new ones. Use resume() to continue execution.

pub fn resume(&self)

Resume workflow execution after pause

pub fn is_paused(&self) -> bool

Check if the workflow is paused

pub fn pause_handles(&self) -> (Arc<AtomicBool>, Arc<Notify>)

Get cloneable handles for external pause/resume control

Returns (paused_flag, resume_notify) that can be used by the TUI to control pause state externally.

pub fn event_log(&self) -> &EventLog

Get the event log for inspection/export

pub async fn run(&mut self) -> Result<String, NikaError>

Main execution loop