feat(config): add configuration file support

- Add wharf-core config module with TOML loading
- Define YachtAgentConfig and WharfCliConfig structs
- Implement ConfigLoader for hierarchical config discovery
  (project-local > user > system > defaults)
- Integrate config loading into yacht-agent main
- CLI args take precedence over config file values
- Add example config files in examples/
- Update STATE.scm with session progress

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: Jonathan D.A. Jewell

Cargo.lock

@@ -9,7 +9,7 @@
       ((version . "1.0.0")
        (schema-version . "1")
        (created . "2025-01-10T13:50:29+00:00")
-       (updated . "2025-01-12T06:00:00+00:00")
+       (updated . "2025-01-12T07:00:00+00:00")
        (project . "project-wharf")
        (repo . "https://github.com/hyperpolymath/project-wharf")))
 
@@ -20,16 +20,16 @@
 
     (current-position
       ((phase . "Alpha Development")
-       (overall-completion . 55)
+       (overall-completion . 60)
        (components
          ((wharf-core
             ((status . "functional")
-             (completion . 60)
-             (notes . "PolicyEngine, IntegrityChecker, SyncManager implemented")))
+             (completion . 70)
+             (notes . "PolicyEngine, IntegrityChecker, SyncManager, ConfigLoader implemented")))
           (yacht-agent
             ((status . "in-progress")
-             (completion . 60)
-             (notes . "DB proxy, API, eBPF loader, nftables fallback complete")))
+             (completion . 65)
+             (notes . "DB proxy, API, eBPF loader, nftables fallback, config loading complete")))
           (wharf-cli
             ((status . "in-progress")
              (completion . 35)
@@ -43,15 +43,16 @@
           "SQL AST parsing for zone classification"
           "BLAKE3 file integrity manifests"
           "eBPF XDP firewall loader (userspace)"
-          "rsync-based file synchronization"))))
+          "nftables fallback firewall"
+          "rsync-based file synchronization"
+          "Configuration file loading (TOML)"))))
 
     (route-to-mvp
       ((milestones
         ((core-hardening
            ((target-completion . 70)
-            (items . ("Complete nftables fallback"
-                      "Wire integrity ops in CLI"
-                      "Add configuration file support"))
+            (items . ("Wire integrity ops in CLI"
+                      "Add config loading to wharf-cli"))
             (status . "in-progress")))
          (nebula-integration
            ((target-completion . 85)
@@ -69,20 +70,28 @@
     (blockers-and-issues
       ((critical . ())
        (high . ())
-       (medium . ("CLI integrity commands not wired"
-                  "No configuration file support"))
+       (medium . ("CLI integrity commands not wired"))
        (low . ("Some unused function warnings in wharf-cli"))))
 
     (critical-next-actions
       ((immediate . ("Wire integrity commands in CLI"
-                     "Add configuration file support"))
+                     "Start Nebula/Mooring integration"))
        (this-week . ("Test nftables on production system"
                      "Test eBPF compilation with bpf-linker"))
-       (this-month . ("Begin Nebula mesh integration"
+       (this-month . ("Implement Mooring protocol"
                       "Performance optimization"))))
 
     (session-history
-      (((timestamp . "2025-01-12T06:00:00Z")
+      (((timestamp . "2025-01-12T07:00:00Z")
+        (session-id . "config-support")
+        (accomplishments
+          ("Created wharf-core config module with TOML support"
+           "Added ConfigLoader for hierarchical config discovery"
+           "Defined YachtAgentConfig and WharfCliConfig structs"
+           "Integrated config loading into yacht-agent main"
+           "Config merges with CLI args (CLI takes precedence)"
+           "Created example config files in examples/")))
+       ((timestamp . "2025-01-12T06:00:00Z")
         (session-id . "firewall-blockers")
         (accomplishments
           ("Implemented NftablesManager with full runtime API"

STATE.scm

@@ -31,6 +31,7 @@ use tokio::sync::{Mutex, RwLock};
 use tracing::{error, info, warn, Level};
 use tracing_subscriber::FmtSubscriber;
 
+use wharf_core::config::{ConfigLoader, YachtAgentConfig};
 use wharf_core::db_policy::{DatabasePolicy, PolicyEngine, QueryAction};
 use wharf_core::types::HeaderPolicy;
 
@@ -175,8 +176,48 @@ impl AgentState {
 async fn main() -> anyhow::Result<()> {
     let args = Args::parse();
 
-    // Set up logging based on verbosity
-    let log_level = match args.verbose {
+    // Load configuration file (CLI args override config file values)
+    let config_loader = ConfigLoader::new();
+    let config = config_loader.load_yacht_agent_config().unwrap_or_else(|e| {
+        eprintln!("Warning: Failed to load config file: {}. Using defaults.", e);
+        YachtAgentConfig::default()
+    });
+
+    // Merge config with CLI args (CLI takes precedence)
+    let protocol = if args.protocol != "mysql" {
+        args.protocol.clone()
+    } else {
+        config.db_proxy.protocol.clone()
+    };
+    let listen_port = args.listen_port;
+    let shadow_host = if args.shadow_host != "127.0.0.1" {
+        args.shadow_host.clone()
+    } else {
+        config.db_proxy.shadow_host.clone()
+    };
+    let shadow_port = if args.shadow_port != 33060 {
+        args.shadow_port
+    } else {
+        config.db_proxy.shadow_port
+    };
+    let firewall_mode = if args.firewall_mode != "nftables" {
+        args.firewall_mode.clone()
+    } else {
+        config.firewall.mode.clone()
+    };
+    let xdp_interface = if args.xdp_interface != "eth0" {
+        args.xdp_interface.clone()
+    } else {
+        config.firewall.xdp_interface.clone()
+    };
+
+    // Set up logging based on verbosity (CLI overrides config)
+    let verbosity = if args.verbose > 0 {
+        args.verbose
+    } else {
+        config.logging.verbosity
+    };
+    let log_level = match verbosity {
         0 => Level::INFO,
         1 => Level::DEBUG,
         _ => Level::TRACE,
@@ -192,15 +233,15 @@ async fn main() -> anyhow::Result<()> {
 
     info!("Yacht Agent starting...");
     info!("Version: {}", wharf_core::VERSION);
-    info!("Protocol: {}", args.protocol);
-    info!("Masquerade port: {}", args.listen_port);
-    info!("Shadow DB: {}:{}", args.shadow_host, args.shadow_port);
-    info!("Firewall mode: {}", args.firewall_mode);
+    info!("Protocol: {}", protocol);
+    info!("Masquerade port: {}", listen_port);
+    info!("Shadow DB: {}:{}", shadow_host, shadow_port);
+    info!("Firewall mode: {}", firewall_mode);
 
     // Initialize firewall based on mode
-    let _firewall: Firewall = match args.firewall_mode.as_str() {
+    let _firewall: Firewall = match firewall_mode.as_str() {
         "ebpf" => {
-            info!("Attempting to load eBPF XDP firewall on {}", args.xdp_interface);
+            info!("Attempting to load eBPF XDP firewall on {}", xdp_interface);
 
             // Look for the eBPF object file in standard locations
             let ebpf_paths = [
@@ -213,9 +254,9 @@ async fn main() -> anyhow::Result<()> {
 
             match ebpf_path {
                 Some(path) => {
-                    match ebpf::try_load_shield(path, &args.xdp_interface) {
+                    match ebpf::try_load_shield(path, &xdp_interface) {
                         Some(shield) => {
-                            info!("eBPF XDP firewall loaded successfully on {}", args.xdp_interface);
+                            info!("eBPF XDP firewall loaded successfully on {}", xdp_interface);
                             Firewall::Ebpf(shield)
                         }
                         None => {

bin/yacht-agent/src/main.rs

@@ -27,5 +27,8 @@ anyhow = { workspace = true }
 # Logging
 tracing = { workspace = true }
 
+# Platform-independent directories
+dirs = "5.0"
+
 [dev-dependencies]
 tempfile = "3.10"