[feat] introduced server and cli crates with foundational HTTP server and CLI implementation, including routing, health check, and configuration setup

backend-rust/crates/cli/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "cli"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+anyhow = { workspace = true }
+tokio = { workspace = true }
+serde = { workspace = true }
+serde_json = { workspace = true }
+toml = { workspace = true }
+dotenv = { workspace = true }
+
+api = { path = "../api" }
+server = { path = "../server" }

backend-rust/crates/cli/src/main.rs

@@ -0,0 +1,70 @@
+use anyhow::Result;
+use api::config::Cli;
+use dotenv::dotenv;
+use std::{env, net::SocketAddr, str::FromStr};
+use tokio::signal;
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    dotenv().ok();
+    let args: Vec<String> = env::args().collect();
+
+    match args.get(1).map(|s| s.as_str()) {
+        Some("serve") => serve(args).await,
+        Some("print-config") => print_config(),
+        _ => {
+            print_help();
+            Ok(())
+        }
+    }
+}
+
+fn print_help() {
+    eprintln!(
+        "Usage:
+  cli serve [--addr 0.0.0.0:8080]
+  cli print-config
+
+Environment:
+  These may influence runtime behavior.
+
+Notes:
+  - 'serve' runs the HTTP server.
+  - 'print-config' prints the default CLI configuration in JSON."
+    );
+}
+
+async fn serve(args: Vec<String>) -> Result<()> {
+    // naive flag parse: look for "--addr host:port"
+    let mut addr: SocketAddr = SocketAddr::from_str("127.0.0.1:8080")?;
+    let mut i = 2;
+    while i + 1 < args.len() {
+        if args[i] == "--addr" {
+            addr = SocketAddr::from_str(&args[i + 1])?;
+            i += 2;
+        } else {
+            i += 1;
+        }
+    }
+
+    let server_task = tokio::spawn(async move { server::start_server(addr).await });
+
+    // graceful shutdown via Ctrl+C
+    tokio::select! {
+        res = server_task => {
+            res??;
+        }
+        _ = signal::ctrl_c() => {
+            eprintln!("Shutting down...");
+        }
+    }
+
+    Ok(())
+}
+
+fn print_config() -> Result<()> {
+    let cfg = Cli::default();
+    let json = serde_json::to_string_pretty(&cfg)?;
+    println!("{json}");
+    Ok(())
+}