feat: Improving locking mechanism

Author: sousandrei

src/main.rs

@@ -4,7 +4,7 @@ use std::env;
 use std::sync::Arc;
 use tokio::signal::unix::{signal, SignalKind};
 use tokio::sync::mpsc;
-use tokio::sync::Mutex;
+use tokio::sync::RwLock;
 use tracing::{error, info};
 
 mod api;
@@ -32,7 +32,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
     };
 
     let state = State {
-        vms: Arc::new(Mutex::new(Vec::new())),
+        vms: Arc::new(RwLock::new(Vec::new())),
         tmp_dir: cli_options.tmp_dir,
         log_dir: cli_options.log_dir,
         assets_dir: cli_options.assets_dir,
@@ -73,7 +73,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
 
     graceful.await?;
 
-    let vms = state_ptr.vms.lock().await;
+    let vms = state_ptr.vms.read().await;
 
     for v in vms.iter() {
         info!("Terminating [{}]", v.name);

src/state.rs

@@ -1,6 +1,6 @@
 use serde::{Deserialize, Serialize};
 use std::sync::Arc;
-use tokio::sync::Mutex;
+use tokio::sync::RwLock;
 
 #[derive(Serialize, Deserialize, Debug, Clone)]
 pub struct Vm {
@@ -9,7 +9,7 @@ pub struct Vm {
 }
 
 pub struct State {
-    pub vms: Arc<Mutex<Vec<Vm>>>,
+    pub vms: Arc<RwLock<Vec<Vm>>>,
     pub tmp_dir: String,
     pub log_dir: String,
     pub assets_dir: String,
@@ -20,7 +20,7 @@ pub struct State {
 pub type StatePtr = Arc<State>;
 
 pub async fn get_vms(state_ptr: StatePtr) -> Vec<Vm> {
-    let vms = state_ptr.vms.lock().await;
+    let vms = state_ptr.vms.read().await;
 
     let mut new_vms: Vec<Vm> = Vec::new();
     for (_, item) in vms.iter().enumerate() {
@@ -31,7 +31,7 @@ pub async fn get_vms(state_ptr: StatePtr) -> Vec<Vm> {
 }
 
 pub async fn add_vm(state_ptr: StatePtr, name: &str, pid: u32) {
-    let mut vms = state_ptr.vms.lock().await;
+    let mut vms = state_ptr.vms.write().await;
 
     vms.push(Vm {
         name: String::from(name),
@@ -40,15 +40,15 @@ pub async fn add_vm(state_ptr: StatePtr, name: &str, pid: u32) {
 }
 
 pub async fn remove_vm(state_ptr: StatePtr, name: &str) {
-    let mut vms = state_ptr.vms.lock().await;
+    let mut vms = state_ptr.vms.write().await;
 
     if let Some(index) = vms.iter().position(|vm| vm.name == name) {
         vms.remove(index);
     }
 }
 
 pub async fn get_vm_pid(state_ptr: StatePtr, name: &str) -> Option<u32> {
-    let vms = state_ptr.vms.lock().await;
+    let vms = state_ptr.vms.read().await;
 
     if let Some(index) = vms.iter().position(|vm| vm.name == name) {
         return Option::Some(vms[index].pid);