chore: update config loading logic to use MC_PROJECT_ROOT for configuration path and improve error handling for missing config files in load_config function

Author: kaihiroi

src/config.rs

@@ -121,17 +121,20 @@ impl Default for ReferenceConfig {
 
 // Example function to load config (will be used in main.rs)
 pub fn load_config() -> Result<McpConfig> {
-    // Support MCP_CONFIG_PATH env var for config file path
-    let config_path_env = std::env::var("MCP_CONFIG_PATH").ok();
-    let config_path = config_path_env.clone().unwrap_or_else(|| "mcp_config.toml".to_string());
-
-    if let Some(ref env_path) = config_path_env {
-        if !std::path::Path::new(env_path).exists() {
-            return Err(anyhow::anyhow!("Config file not found at MCP_CONFIG_PATH: {}", env_path));
-        }
-        log::info!("MCP_CONFIG_PATH is set: {}", env_path);
+    // Always use MC_PROJECT_ROOT for config path
+    let project_root = std::env::var("MC_PROJECT_ROOT")
+        .map_err(|_| anyhow::anyhow!("MC_PROJECT_ROOT is not set. Please set MC_PROJECT_ROOT to your project root directory."))?;
+    let project_root_path = std::path::Path::new(&project_root);
+    if !project_root_path.exists() {
+        return Err(anyhow::anyhow!("MC_PROJECT_ROOT does not exist: {}", project_root));
+    }
+    let config_path = project_root_path.join("mcp_config.toml");
+    let config_file_exists = config_path.exists();
+    if config_file_exists {
+        log::info!("MC_PROJECT_ROOT is set: {}", project_root_path.display());
+        log::info!("Loading config from: {}", config_path.display());
     } else {
-        log::info!("MCP_CONFIG_PATH not set, falling back to default: {}", config_path);
+        log::warn!("Config file not found at: {}. Using defaults.", config_path.display());
     }
     // Use ReferenceConfig::default() to get defaults including calculated paths
     let default_config = McpConfig {
@@ -140,13 +143,13 @@ pub fn load_config() -> Result<McpConfig> {
         setup: SetupConfig::default(),
     };
 
-    let figment = Figment::new()
+    let mut figment = Figment::new()
         // Start with our programmatically defined defaults
-        .merge(Serialized::defaults(default_config)) // Use our instance
-        // Merge TOML file if it exists
-        .merge(Toml::file(&config_path))
-        // Merge environment variables prefixed with MCP_
-        .merge(Env::prefixed("MCP_").split("__"));
+        .merge(Serialized::defaults(default_config)); // Use our instance
+    if config_file_exists {
+        figment = figment.merge(Toml::file(&config_path));
+    }
+    figment = figment.merge(Env::prefixed("MCP_").split("__"));
 
     let config: McpConfig = figment.extract().context("Failed to extract McpConfig")?;
     validate_config(&config)?;

src/main.rs

@@ -570,7 +570,20 @@ impl MyHandler {
         use std::env;
         use std::fs;
         use std::process::Command;
-        // 1. Check if current directory is empty
+        // 1. Get MC_PROJECT_ROOT and move to it
+        let project_root = std::env::var("MC_PROJECT_ROOT")
+            .map_err(|_| McpError::internal_error("MC_PROJECT_ROOT is not set. Please set MC_PROJECT_ROOT to your project root directory.", None))?;
+        let project_root_path = std::path::Path::new(&project_root);
+        if !project_root_path.exists() {
+            return Ok(CallToolResult::error(vec![Content::text(format!(
+                "MC_PROJECT_ROOT does not exist: {}", project_root
+            ))]));
+        }
+        std::env::set_current_dir(&project_root_path)
+            .map_err(|e| McpError::internal_error(format!("Failed to set current dir: {e}"), None))?;
+        log::info!("Changed working directory to MC_PROJECT_ROOT: {:?}", project_root_path);
+        // 2. Check if current directory is empty
+        log::info!("Current working directory for mc_setup: {:?}", env::current_dir());
         let current_dir = env::current_dir().map_err(|e| {
             McpError::internal_error(format!("Failed to get current dir: {e}"), None)
         })?;
@@ -588,20 +601,20 @@ impl MyHandler {
         if force && !is_empty {
             log::warn!("[setup.force=true] Forcing setup: existing files in the directory may be overwritten.");
         }
-        // 2. Run forge init . -t <repo>
+        // 3. Run forge init . -t <repo>
         // Use local template cache if specified
         let template_arg = if let Ok(local_template) = std::env::var("MC_TEMPLATE_CACHE") {
             local_template
         } else {
             MC_TEMPLATE_REPO.to_string()
         };
 
-        // Use output() to capture stderr as well
         let mut cmd = Command::new("forge");
         cmd.args(["init", ".", "-t", &template_arg]);
         if force {
             cmd.arg("--no-git");
         }
+        log::info!("Running forge init command: {:?}", cmd);
         let output_result = cmd.output();
 
         match output_result {