HydraCache 0.28.0

HydraCache 0.28.0

Status: published.

0.28.0 focuses on cluster runtime lifecycle diagnostics. The goal is to make
embedded cluster components easier to observe and shut down gracefully without
turning HydraCache into a daemon.

Highlights

• Added reusable lifecycle status/diagnostics types in hydracache.
• Exposed admission bridge background-loop lifecycle state.
• Included local client/member runtime lifecycle snapshots in cluster
  diagnostics.
• Surfaced lifecycle data in sandbox/actuator-style reports.
• Extended README, rustdoc, and testing docs with lifecycle examples.

Intended Shape

Applications should be able to inspect lifecycle state without scraping logs:

use hydracache::{
    ClusterAdmissionBridge, ClusterLifecycleStatus, InMemoryCluster,
    InMemoryClusterDiscovery,
};
use std::sync::Arc;

# #[tokio::main]
# async fn main() -> hydracache::CacheResult<()> {
let discovery = Arc::new(InMemoryClusterDiscovery::new());
let control_plane = Arc::new(InMemoryCluster::new("orders"));
let bridge = ClusterAdmissionBridge::new(discovery, control_plane);

assert_eq!(
    bridge.lifecycle_diagnostics().status,
    ClusterLifecycleStatus::Idle
);

let handle = bridge.start();
assert!(bridge.lifecycle_diagnostics().is_running());

handle.shutdown().await;
assert!(bridge.lifecycle_diagnostics().is_stopped());
# Ok(())
# }

Client/member cache diagnostics should also describe the local runtime state:

use std::sync::Arc;

use hydracache::{HydraCache, InMemoryCluster};

# #[tokio::main]
# async fn main() -> hydracache::CacheResult<()> {
let cluster = Arc::new(InMemoryCluster::new("orders"));
let member = HydraCache::member()
    .shared_cluster(cluster)
    .node_id("member-a")
    .start()
    .await?;

let diagnostics = member.cluster_diagnostics().expect("cluster runtime");
assert!(diagnostics.lifecycle.is_running());

member.leave_cluster().await?;
assert!(member.cluster_diagnostics().unwrap().lifecycle.is_stopped());
# Ok(())
# }

Validation

Focused checks:

cargo test -p hydracache --lib --locked lifecycle
cargo test -p hydracache --lib --locked admission_bridge
cargo test -p hydracache --lib --locked cluster
cargo test -p hydracache-sandbox --lib --locked openapi_document_describes_demo_and_actuator_routes
cargo test -p hydracache-sandbox --lib --locked swagger_api_exercises_library_features_and_reports
cargo test --doc -p hydracache --locked

Expected full release gate:

cargo fmt --all -- --check
cargo check --workspace --all-targets --locked
cargo test --workspace --locked
cargo clippy --workspace --all-targets --all-features --locked -- -D warnings
cargo test --doc --workspace --locked
$env:RUSTDOCFLAGS='-D warnings'; cargo doc --workspace --no-deps --locked

Validated locally on 2026-06-12 with:

• cargo fmt --all -- --check
• cargo check --workspace --all-targets --locked
• cargo test --workspace --locked
• cargo clippy --workspace --all-targets --all-features --locked -- -D warnings
• cargo test --doc --workspace --locked
• $env:RUSTDOCFLAGS='-D warnings'; cargo doc --workspace --no-deps --locked

Published to crates.io on 2026-06-12:

• hydracache-core 0.28.0
• hydracache-macros 0.28.0
• hydracache 0.28.0
• hydracache-cluster-chitchat 0.28.0
• hydracache-cluster-raft 0.28.0
• hydracache-cluster 0.28.0
• hydracache-cluster-transport-axum 0.28.0
• hydracache-observability 0.28.0
• hydracache-actuator-axum 0.28.0
• hydracache-db 0.28.0
• hydracache-sqlx 0.28.0

Registry metadata was verified with cargo info <crate>@0.28.0 --registry crates-io from outside the workspace.

See
the 0.28.0 plan
for the implementation checklist.