Struct ConfigManager 

pub struct ConfigManager { /* private fields */ }

Lock Ordering Invariant

To prevent deadlock, ALL methods acquiring multiple locks MUST respect this canonical ordering:

1. reload_mutex (coarse-grained serialization)
2. config (fine-grained data access)

CRITICAL: Never hold config write lock while requesting reload_mutex.

Atomic Operation Ordering

Atomic operations follow happens-before relationships:

set_value() → increment generation → send SaveRequest
    ↓
background_saver receives → read config + generation → write disk

Sequential consistency (Ordering::SeqCst) ensures all threads see generation increments in the same order.

Concurrent Safety

• config: RwLock allows multiple concurrent readers, single writer
• generation: AtomicU64 provides lock-free increment
• saving: AtomicBool prevents file watcher self-trigger
• reload_mutex: Serializes reload operations
• save_sender: UnboundedSender is lock-free

Implementations

impl ConfigManager

pub fn new() -> Self

pub async fn init(&self) -> Result<(), McpError>

Initialize configuration from disk and environment variables

Errors

Returns error if config directory cannot be created or config file cannot be read/written

pub async fn reload(&self) -> Result<(), McpError>

Reload configuration from disk

Re-reads the config file and updates in-memory state. Serialized with mutex to prevent concurrent reloads (Race #3). Uses the same recovery cascade as init() to handle corruption. Environment variable overrides (KODEGEN_ALLOWED_DIRS, KODEGEN_DENIED_DIRS) are preserved and re-applied after loading.

Errors

Returns error if config file cannot be read or parsed

pub async fn enable_file_watching(&mut self) -> Result<(), McpError>

Enable automatic config file watching

Starts monitoring the config file for changes. When changes are detected (after 1-second debounce), automatically calls reload().

This is optional and should be enabled via CLI flag (e.g., --watch-config).

Errors

Returns error if file watching cannot be initialized

pub fn get_config(&self) -> ServerConfig

pub fn get_file_read_line_limit(&self) -> usize

pub fn get_file_write_line_limit(&self) -> usize

pub fn get_blocked_commands(&self) -> Vec<String>

pub fn get_fuzzy_search_threshold(&self) -> f64

pub fn get_http_connection_timeout_secs(&self) -> u64

pub fn get_path_validation_timeout_ms(&self) -> u64

pub fn get_value(&self, key: &str) -> Option<ConfigValue>

pub async fn set_value( &self, key: &str, value: ConfigValue, ) -> Result<(), McpError>

Set a configuration value by key

Thread-safe with generation tracking to prevent lost updates. Increments generation counter atomically after modification.

Errors

Returns error if the key is unknown, value type is invalid, or config cannot be saved

pub async fn set_client_info(&self, client_info: ClientInfo)

Store client information from MCP initialization

Updates in-memory state immediately and queues async save to disk. Disk write errors are logged but not propagated (fire-and-forget pattern). Use get_save_error_count() to check for save failures.

pub fn get_client_info(&self) -> Option<ClientInfo>

Get current client information

pub fn get_client_history(&self) -> Vec<ClientRecord>

Get client connection history

pub fn get_save_error_count() -> usize

Get total count of config save failures since server start

This counter tracks background save failures (disk write errors). Used for observability and monitoring config persistence issues.

Trait Implementations

impl Clone for ConfigManager

fn clone(&self) -> ConfigManager

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Default for ConfigManager

fn default() -> Self

Returns the “default value” for a type.