Struct SupervisionTreeHandle 

pub struct SupervisionTreeHandle { /* private fields */ }

A read-only handle for taking snapshots of a supervision tree.

Obtained from Supervisor::tree_handle. Cheap to clone, safe to share across tasks and threads, and deliberately incapable of anything but observation – it cannot spawn children or otherwise affect the tree it reports on.

A handle can be taken before the supervisor starts, and remains valid across every restart of it.

Implementations

impl SupervisionTreeHandle

pub fn name(&self) -> &str

Returns the identifier of the supervisor at the root of this handle’s view.

pub fn snapshot_json(&self) -> String

Renders the current state of the supervision tree as pretty-printed JSON.

Returns a JSON object describing the failure if the tree can’t be serialized, so that a caller writing a diagnostic artifact always has something to write.

pub fn api_handler(&self) -> SupervisionTreeAPIHandler

Creates a SupervisionTreeAPIHandler serving snapshots of this tree.

pub fn worker(&self) -> SupervisionTreeWorker

Creates a SupervisionTreeWorker that publishes this tree over the control plane.

pub fn snapshot(&self) -> TreeSnapshot

Captures the current state of the supervision tree.

Descends from this handle’s supervisor through every child, nesting each child’s own children beneath it.

Consistency

The tree is read one supervisor at a time, so a snapshot is not a globally atomic view: a child may start or exit while the walk is in progress, and the result then mixes observations from slightly different instants. This is deliberate. Reading the whole tree atomically would mean holding every supervisor’s bookkeeping at once, which would let an operator-facing diagnostics call stall supervision across the entire process – a far worse property than a snapshot whose nodes are microseconds apart.

Trait Implementations

impl Clone for SupervisionTreeHandle

fn clone(&self) -> SupervisionTreeHandle

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.