Rename main folders and write sql backend adaptor

backend/src/main.rs

@@ -0,0 +1,33 @@
+use std::net::SocketAddr;
+
+use axum::{routing::get, Router, Server};
+use data::adaptor::Adaptor;
+use sql_adaptor::PostgresAdaptor;
+
+#[cfg(debug_assertions)]
+const MODE: &str = "debug";
+
+#[cfg(not(debug_assertions))]
+const MODE: &str = "release";
+
+#[tokio::main]
+async fn main() {
+    // Load env
+    dotenv::dotenv().ok();
+
+    PostgresAdaptor::new().await;
+
+    let app = Router::new().route("/", get(get_root));
+
+    let addr = SocketAddr::from(([127, 0, 0, 1], 3000));
+
+    println!("Crab Fit API listening at http://{} in {} mode", addr, MODE);
+    Server::bind(&addr)
+        .serve(app.into_make_service())
+        .await
+        .unwrap();
+}
+
+async fn get_root() -> String {
+    format!("Crab Fit API v{}", env!("CARGO_PKG_VERSION"))
+}