Struct SelectionContext 

pub struct SelectionContext {
    pub estimated_cost: Option<f64>,
    pub hash_key: Option<u64>,
    pub tags: Option<HashMap<String, String>>,
    pub exclude: Option<Vec<usize>>,
}

Context provided to strategies during node selection.

Examples

use loadwise::SelectionContext;

// Empty context (most strategies work fine without it).
let ctx = SelectionContext::default();

// With a hash key for consistent hashing.
let ctx = SelectionContext::builder()
    .hash_key(42)
    .build();

// With estimated request cost and tags.
let ctx = SelectionContext::builder()
    .estimated_cost(150.0)
    .tags([("model".into(), "gpt-4".into())].into())
    .build();

assert_eq!(ctx.tag("model"), Some("gpt-4"));

// Exclude specific indices (e.g., retry after failure).
let ctx = SelectionContext::builder()
    .exclude(vec![0, 2])
    .build();
assert!(ctx.is_excluded(0));
assert!(!ctx.is_excluded(1));

Fields

estimated_cost: Option<f64>

Estimated cost/weight of this request (e.g., token count).

hash_key: Option<u64>

Hash key for consistent hashing strategies.

tags: Option<HashMap<String, String>>

Arbitrary tags for routing decisions. None by default to avoid allocation.

exclude: Option<Vec<usize>>

Indices to skip during selection (for retry scenarios). None by default to avoid allocation.

Implementations

impl SelectionContext

pub fn builder() -> SelectionContextBuilder

Create an instance of SelectionContext using the builder syntax

impl SelectionContext

pub fn tag(&self, key: &str) -> Option<&str>

Look up a tag value by key.

pub fn is_excluded(&self, idx: usize) -> bool

Returns true if the given index should be skipped.

Uses linear search — O(n) in the size of the exclude list. Fine for typical retry scenarios (1–3 entries); for larger lists consider pre-filtering candidates instead.

Trait Implementations

impl Clone for SelectionContext

fn clone(&self) -> SelectionContext

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SelectionContext

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

Formats the value using the given formatter.

impl Default for SelectionContext

fn default() -> SelectionContext

Returns the “default value” for a type.