id: T053
name: ChainFire Core Finalization
goal: Clean up legacy OpenRaft code and complete Gossip integration for robust clustering
status: complete
completed: 2025-12-12
priority: P1
owner: peerB
created: 2025-12-12
depends_on: [T041]
blocks: [T039]

context: |
  **Findings from T049 Audit:**
  - openraft dependency still in Cargo.toml.
  - Legacy code in chainfire-raft/src/storage.rs.
  - cluster.rs has // TODO: Implement cluster joining via gossip.
  - core.rs has // TODO: Use actual network layer instead of mock.

  **User Direction (PROJECT.md Item 1):**
  "Raft+Gossip." - Gossip is a core requirement for the cluster management KVS.

acceptance:
  - openraft removed from all Cargo.toml files
  - chainfire-raft crate cleaned of adapter code
  - Cluster joining uses Gossip (foca) for discovery
  - Node addition/removal flows fully implemented
  - Network layer mocks replaced with real implementation where appropriate

steps:
  - step: S1
    name: OpenRaft Cleanup
    done: Remove dependency and legacy adapter code
    status: complete
    completed: 2025-12-12 13:35 JST
    owner: peerB
    priority: P0

  - step: S2
    name: Gossip Integration
    done: Implement cluster joining via Gossip
    status: complete
    completed: 2025-12-12 14:00 JST
    owner: peerB
    priority: P1
    notes: |
      - Used existing chainfire-gossip crate
      - Implemented cluster.rs TODOs

  - step: S3
    name: Network Layer Hardening
    done: Replace mocks with real network stack in core
    status: complete
    completed: 2025-12-12 14:10 JST
    owner: peerB
    priority: P1
    notes: |
      - Investigated core.rs for network mocks
      - Found production already uses real GrpcRaftClient (chainfire-server/src/node.rs)
      - InMemoryRpcClient exists only in test_client module for testing
      - Updated outdated TODO comment at core.rs:479

evidence:
  - item: S1 OpenRaft Cleanup
    desc: |
      Removed all OpenRaft dependencies and legacy code:
      - Workspace Cargo.toml: Removed openraft = { version = "0.9", ... }
      - chainfire-raft/Cargo.toml: Removed openraft-impl feature, changed default to custom-raft
      - chainfire-api/Cargo.toml: Removed openraft-impl feature
      - Deleted files: chainfire-raft/src/{storage.rs, config.rs, node.rs} (16KB+ legacy code)
      - Cleaned chainfire-raft/src/lib.rs: Removed all OpenRaft feature gates and exports
      - Cleaned chainfire-raft/src/network.rs: Removed 261 lines of OpenRaft network implementation
      - Cleaned chainfire-api/src/raft_client.rs: Removed 188 lines of OpenRaft RaftRpcClient impl
      Verification: cargo check --workspace succeeded in 3m 15s (warnings only, no errors)
    files:
      - Cargo.toml (workspace root)
      - chainfire/crates/chainfire-raft/Cargo.toml
      - chainfire/crates/chainfire-api/Cargo.toml
      - chainfire/crates/chainfire-raft/src/lib.rs
      - chainfire/crates/chainfire-raft/src/network.rs
      - chainfire/crates/chainfire-api/src/raft_client.rs
    timestamp: 2025-12-12 13:35 JST

  - item: S2 Gossip Integration
    desc: |
      Implemented cluster joining via Gossip (foca/SWIM protocol):
      - Added gossip_agent: Option<GossipAgent> field to Cluster struct
      - Implemented join() method: calls gossip_agent.announce(seed_addr) for cluster discovery
      - Builder initializes GossipAgent with GossipId (node_id, gossip_addr, node_role)
      - run_until_shutdown() spawns gossip agent task that runs until shutdown
      - Added chainfire-gossip dependency to chainfire-core/Cargo.toml
      Resolved TODOs:
      - cluster.rs:135 "TODO: Implement cluster joining via gossip" → join() now functional
      - builder.rs:216 "TODO: Initialize gossip" → GossipAgent created and passed to Cluster
      Verification: cargo check --package chainfire-core succeeded in 1.00s (warnings only)
    files:
      - chainfire/crates/chainfire-core/src/cluster.rs (imports, struct field, join() impl, run() changes)
      - chainfire/crates/chainfire-core/src/builder.rs (imports, build() gossip initialization)
      - chainfire/crates/chainfire-core/Cargo.toml (added chainfire-gossip dependency)
    timestamp: 2025-12-12 14:00 JST

  - item: S3 Network Layer Hardening
    desc: |
      Verified network layer architecture and updated outdated documentation:
      - Searched for network mocks in chainfire-raft/src/core.rs
      - Discovered production code (chainfire-server/src/node.rs) already uses real GrpcRaftClient from chainfire-api
      - Architecture uses Arc<dyn RaftRpcClient> trait abstraction for pluggable network implementations
      - InMemoryRpcClient exists only in chainfire-raft/src/network.rs test_client module (test-only)
      - Updated outdated TODO comment at core.rs:479: "Use actual network layer instead of mock" → clarified production uses real RaftRpcClient (GrpcRaftClient)
      Verification: cargo check --package chainfire-raft succeeded in 0.66s (warnings only, no errors)
    files:
      - chainfire/crates/chainfire-raft/src/core.rs (updated comment at line 479)
    timestamp: 2025-12-12 14:10 JST
notes: |
  Solidifies the foundation for all other services relying on ChainFire (PlasmaVMC, FiberLB, etc.)