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use std::sync::Arc;
use super::LoadBalancingStrategy;
pub struct SingleNode<N> {
cluster: Vec<Arc<N>>,
}
impl<N> SingleNode<N> {
pub fn new() -> Self {
SingleNode { cluster: vec![] }
}
}
impl<N> From<Vec<Arc<N>>> for SingleNode<N> {
fn from(cluster: Vec<Arc<N>>) -> SingleNode<N> {
SingleNode { cluster: cluster }
}
}
impl<N> LoadBalancingStrategy<N> for SingleNode<N> where N: Sync + Send {
fn init(&mut self, cluster: Vec<Arc<N>>) {
self.cluster = cluster;
}
fn next(&self) -> Option<Arc<N>> {
self.cluster.get(0).map(|node| node.clone())
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn single_node() {
let nodes = vec!["a"];
let nodes_c = nodes.clone();
let load_balancer = SingleNode::from(nodes.iter().map(|value| Arc::new(*value)).collect::<Vec<Arc<&str>>>());
assert_eq!(&nodes_c[0], load_balancer.next().unwrap().as_ref());
assert_eq!(&nodes_c[0], load_balancer.next().unwrap().as_ref());
}
}