added commentation

WatcherAgent/src/main.rs

@@ -1,20 +1,55 @@
-/// WatcherAgent - A Rust-based system monitoring agent
-/// This agent collects hardware metrics and sends them to a backend server.
-/// It supports CPU, GPU, RAM, disk, and network metrics.
+
+//! # WatcherAgent
+//!
+//! **WatcherAgent** is a cross-platform system monitoring agent written in Rust.
+//!
+//! ## Overview
+//! This agent collects real-time hardware metrics (CPU, GPU, RAM, disk, network) and communicates with a backend server for registration, reporting, and remote control. It is designed for deployment in environments where automated monitoring and remote management of system resources is required.
+//!
+//! ## Features
+//! - **Hardware Metrics:** Collects CPU, GPU, RAM, disk, and network statistics using platform-specific APIs.
+//! - **Docker Integration:** Detects and manages its own Docker container, supports image updates and container restarts.
+//! - **Server Communication:** Registers with a backend server, sends periodic heartbeats, and reports metrics securely.
+//! - **Remote Commands:** Listens for and executes commands from the backend (e.g., update image, restart container, stop agent).
+//!
+//! ## Modules
+//! - [`api`]: Handles HTTP communication with the backend server (registration, heartbeat, metrics, commands).
+//! - [`hardware`]: Collects hardware metrics from the host system (CPU, GPU, RAM, disk, network).
+//! - [`metrics`]: Orchestrates metric collection and reporting.
+//! - [`models`]: Defines data structures for server communication and metrics.
+//! - [`docker`]: Integrates with Docker for container management and agent lifecycle.
+//!
+//! ## Usage
+//! Run the agent with the backend server URL as an argument:
+//! ```sh
+//! watcheragent <server-url>
+//! ```
+//!
+//! The agent will register itself, start collecting metrics, and listen for remote commands.
+
 pub mod api;
 pub mod hardware;
 pub mod metrics;
 pub mod models;
 pub mod docker;
-
-use std::env;
-use std::error::Error;
-use std::marker::Send;
-use std::marker::Sync;
-use std::result::Result;
 use tokio::task::JoinHandle;
 use bollard::Docker;
 
+
+
+/// Awaits a spawned asynchronous task and flattens its nested `Result` type.
+///
+/// This utility is used to handle the result of a `tokio::spawn`ed task that itself returns a `Result`,
+/// propagating any errors from both the task and its execution.
+///
+/// # Type Parameters
+/// * `T` - The type returned by the task on success.
+///
+/// # Arguments
+/// * `handle` - The `JoinHandle` of the spawned task.
+///
+/// # Returns
+/// * `Result<T, Box<dyn Error + Send + Sync>>` - The result of the task, or an error if the task failed or panicked.
 async fn flatten<T>(
     handle: JoinHandle<Result<T, Box<dyn Error + Send + Sync>>>,
 ) -> Result<T, Box<dyn Error + Send + Sync>> {
@@ -25,6 +60,24 @@ async fn flatten<T>(
     }
 }
 
+/// Main entry point for the WatcherAgent application.
+///
+/// This function performs the following steps:
+/// 1. Initializes the Docker client for container management.
+/// 2. Detects the current running image version.
+/// 3. Parses command-line arguments to obtain the backend server URL.
+/// 4. Registers the agent with the backend server and retrieves its server ID and IP address.
+/// 5. Spawns background tasks for:
+///     - Listening for remote commands from the server
+///     - Sending periodic heartbeat signals
+///     - Collecting and reporting hardware metrics
+/// 6. Waits for all background tasks to complete and logs their results.
+///
+/// # Arguments
+/// * `server-url` - The URL of the backend server to register and report metrics to (passed as a command-line argument).
+///
+/// # Errors
+/// Returns an error if registration or any background task fails, or if required arguments are missing.
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn Error + Send + Sync>> {
     // Initialize Docker client
@@ -54,7 +107,7 @@ async fn main() -> Result<(), Box<dyn Error + Send + Sync>> {
     let server_url = &args[1];
     println!("Server URL: {:?}", server_url);
 
-    // Registration
+    // Registration with backend server
     let (server_id, ip) = match api::register_with_server(&server_url).await {
         Ok((id, ip)) => (id, ip),
         Err(e) => {