solidb 1.0.1

A lightweight, high-performance structured database server written in Rust.
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#[cfg(test)]
use crate::sharding::coordinator::ShardAssignment;
#[cfg(test)]
use crate::sharding::distribution::compute_assignments;
#[cfg(test)]
use std::collections::HashMap;

#[test]
fn test_reproduce_user_overload_issue() {
    // Initial state: Nodes 6745, 6746, 6747
    // S0: P=6745, R=[6746]
    // S1: P=6746, R=[6747]
    // S2: P=6747, R=[6745]
    let mut old_assignments = HashMap::new();
    old_assignments.insert(
        0,
        ShardAssignment {
            shard_id: 0,
            primary_node: "6745".to_string(),
            replica_nodes: vec!["6746".to_string()],
        },
    );
    old_assignments.insert(
        1,
        ShardAssignment {
            shard_id: 1,
            primary_node: "6746".to_string(),
            replica_nodes: vec!["6747".to_string()],
        },
    );
    old_assignments.insert(
        2,
        ShardAssignment {
            shard_id: 2,
            primary_node: "6747".to_string(),
            replica_nodes: vec!["6745".to_string()],
        },
    );

    // 6745 goes DOWN. 6748 comes UP.
    let nodes = vec!["6746".to_string(), "6747".to_string(), "6748".to_string()];

    // Compute RF=2
    let assignments = compute_assignments(&nodes, 3, 2, Some(&old_assignments)).unwrap();

    // Print results for debugging
    for id in 0..3 {
        let a = &assignments[&id];
        println!(
            "Shard {}: P={}, R={:?}",
            id, a.primary_node, a.replica_nodes
        );
    }

    // Check for "assigned twice" as primary
    let mut primary_counts = HashMap::new();
    for a in assignments.values() {
        *primary_counts.entry(a.primary_node.clone()).or_insert(0) += 1;
    }

    // If 6746 is primary for S0 (promoted) and S1 (preserved), it has count 2.
    // While 6748 has count 0.
    assert!(primary_counts.get("6748").copied().unwrap_or(0) > 0,
        "Node 6748 should be recruited as primary for one of the shards to balance load. 6748 count: {:?}",
        primary_counts.get("6748"));
}