Struct Viewport 

pub struct Viewport {
    pub collection: String,
    pub seed_count: u32,
    pub nodes: Vec<ViewportNode>,
    pub edges: Vec<ViewportEdge>,
    pub truncation: TruncationMeta,
}

A populated viewport response. Returned by the (future) runtime call and consumed directly by Red UI.

Fields

collection: String

seed_count: u32

nodes: Vec<ViewportNode>

edges: Vec<ViewportEdge>

truncation: TruncationMeta

Implementations

impl Viewport

pub fn from_visits( request: &ViewportRequest, visits: Vec<ViewportVisitInput>, edges: Vec<ViewportEdge>, ) -> Viewport

Pure builder: given an ordered visit list and the edge list the traversal collected, apply ViewportRequest::node_limit and produce the contract response.

The builder is intentionally pure so the truncation rule lives here once and is testable without a graph store. Runtime wiring (a follow-up slice) will call this after running the real traversal.

Rules:

1. Visits are kept in input order. Callers (the traversal) are responsible for stable ordering — typically BFS by depth, then by node id.
2. The first node_limit visits are returned; the remainder are reported via TruncationMeta::dropped_node_count and TruncationMeta::node_limit_hit.
3. Edges are filtered down to those whose source and target both survived the node cap. An edge to a dropped node would be a dangling reference in the UI.
4. depth_limit_hit is the OR of every surviving visit’s frontier_truncated. A visit dropped by the node cap does not contribute (the UI will surface the node cap instead; re-asking with a larger node limit is the correct fix).

Trait Implementations

impl Clone for Viewport

fn clone(&self) -> Viewport

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Viewport

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl PartialEq for Viewport

fn eq(&self, other: &Viewport) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Viewport