Function decode

nodedb-cluster/src/rpc_codec/raft_rpc.rs:109–144

Decode a framed binary message into a [`RaftRpc`].

(data: &[u8])

/// Decode a framed binary message into a [`RaftRpc`].
pub fn decode(data: &[u8]) -> Result<RaftRpc> {
    let (rpc_type, payload) = super::header::parse_frame(data)?;
    match rpc_type {
        RPC_APPEND_ENTRIES_REQ => raft_msgs::decode_append_entries_req(payload),
        RPC_APPEND_ENTRIES_RESP => raft_msgs::decode_append_entries_resp(payload),
        RPC_REQUEST_VOTE_REQ => raft_msgs::decode_request_vote_req(payload),
        RPC_REQUEST_VOTE_RESP => raft_msgs::decode_request_vote_resp(payload),
        RPC_INSTALL_SNAPSHOT_REQ => raft_msgs::decode_install_snapshot_req(payload),
        RPC_INSTALL_SNAPSHOT_RESP => raft_msgs::decode_install_snapshot_resp(payload),
        RPC_JOIN_REQ => cluster_mgmt::decode_join_req(payload),
        RPC_JOIN_RESP => cluster_mgmt::decode_join_resp(payload),
        RPC_PING => cluster_mgmt::decode_ping(payload),
        RPC_PONG => cluster_mgmt::decode_pong(payload),
        RPC_TOPOLOGY_UPDATE => cluster_mgmt::decode_topology_update(payload),
        RPC_TOPOLOGY_ACK => cluster_mgmt::decode_topology_ack(payload),
        // Discriminants 13/14 (ForwardRequest/ForwardResponse) are retired.
        // A node receiving these has a peer still running an older version.
        // Return a typed error so the operator sees a clear message.
        RPC_FORWARD_REQ | RPC_FORWARD_RESP => Err(ClusterError::Codec {
            detail: format!(
                "rpc_type {rpc_type} is a retired wire variant (ForwardRequest/ForwardResponse, \
                 retired in C-δ.6); upgrade all cluster nodes to remove this peer"
            ),
        }),
        RPC_VSHARD_ENVELOPE => vshard::decode_vshard_envelope(payload),
        RPC_METADATA_PROPOSE_REQ => metadata::decode_metadata_propose_req(payload),
        RPC_METADATA_PROPOSE_RESP => metadata::decode_metadata_propose_resp(payload),
        RPC_EXECUTE_REQ => execute::decode_execute_req(payload),
        RPC_EXECUTE_RESP => execute::decode_execute_resp(payload),
        RPC_DATA_PROPOSE_REQ => data_propose::decode_data_propose_req(payload),
        RPC_DATA_PROPOSE_RESP => data_propose::decode_data_propose_resp(payload),
        _ => Err(ClusterError::Codec {
            detail: format!("unknown rpc_type: {rpc_type}"),
        }),
    }
}

/// Return the total frame size for a buffer that starts with a valid header.
pub fn frame_size(header: &[u8; HEADER_SIZE]) -> Result<usize> {