change worker id to be a uuid

zoidberg_server/Cargo.toml

@@ -16,3 +16,6 @@ clap = "3.2"
 env_logger = "0.9"
 log = "0.4"
 futures = "0.3.24"
+tokio = { version = "1", features = ["full"] }
+chrono = "0.4.22"
+uuid = { version = "1.1.2", features = ["v4"] }

zoidberg_server/src/main.rs

@@ -3,13 +3,17 @@ use actix_web::{
     dev, get, middleware::Logger, post, web, App, Error, FromRequest, HttpRequest, HttpResponse,
     HttpServer, Responder, Result,
 };
+use chrono::Utc;
 use clap;
 use env_logger::Env;
 use futures::future::{err, ok, Ready};
 use log;
 use std::sync::Mutex;
+use std::time::Duration;
+use uuid::Uuid;
 use zoidberg_lib::types::{
-    FetchResponse, Heartbeat, Job, RegisterResponse, StatusRequest, Update, Worker,
+    FetchRequest, FetchResponse, Heartbeat, Job, RegisterResponse, Status, StatusRequest, Update,
+    Worker,
 };
 
 mod webpage;
@@ -17,7 +21,6 @@ mod webpage;
 const VERSION: &str = env!("CARGO_PKG_VERSION");
 
 struct State {
-    counter_workers: Mutex<i32>,
     counter_jobs: Mutex<i32>,
     workers: Mutex<Vec<Worker>>,
     new_jobs: Mutex<Vec<Job>>,
@@ -27,7 +30,6 @@ struct State {
 impl State {
     fn new() -> Self {
         Self {
-            counter_workers: Mutex::new(0),
             counter_jobs: Mutex::new(0),
             workers: Mutex::new(Vec::new()),
             new_jobs: Mutex::new(Vec::new()),
@@ -68,24 +70,40 @@ async fn index(data: web::Data<State>) -> impl Responder {
 
 #[get("/register")]
 async fn register(data: web::Data<State>, _: Authorization) -> Result<impl Responder> {
-    let mut counter_workers = data.counter_workers.lock().unwrap();
-    *counter_workers += 1;
-
     let mut workers = data.workers.lock().unwrap();
+    let uuid = Uuid::new_v4().to_string();
     workers.push(Worker {
-        id: *counter_workers,
+        id: uuid.clone(),
+        last_heartbeat: None,
     });
 
-    log::info!("Registered worker node with id: {}", *counter_workers);
-    Ok(web::Json(RegisterResponse {
-        id: *counter_workers,
-    }))
+    log::info!("Registered worker node with id: {}", uuid);
+    Ok(web::Json(RegisterResponse { id: uuid }))
 }
 
-#[get("/fetch")]
-async fn fetch(data: web::Data<State>, _: Authorization) -> Result<impl Responder> {
+#[post("/fetch")]
+async fn fetch(
+    data: web::Data<State>,
+    f: web::Json<FetchRequest>,
+    _: Authorization,
+) -> Result<impl Responder> {
+    let requesting_worker = f.into_inner().worker_id;
+    {
+        let workers = data.workers.lock().unwrap();
+        if workers.iter().filter(|w| w.id == requesting_worker).count() != 1 {
+            return Ok(web::Json(FetchResponse::Terminate(
+                "Worker not found".into(),
+            )));
+        }
+    }
     let mut new_jobs = data.new_jobs.lock().unwrap();
     if let Some(j) = new_jobs.pop() {
+        let mut jobs = data.jobs.lock().unwrap();
+        for cj in jobs.iter_mut() {
+            if cj.id == j.id {
+                cj.status = Status::Running(requesting_worker.clone())
+            }
+        }
         return Ok(web::Json(FetchResponse::Jobs(vec![j])));
     }
     Ok(web::Json(FetchResponse::Nop))
@@ -133,8 +151,18 @@ async fn update(
 }
 
 #[post("/heartbeat")]
-async fn heartbeat(heartbeat: web::Json<Heartbeat>, _: Authorization) -> Result<String> {
+async fn heartbeat(
+    heartbeat: web::Json<Heartbeat>,
+    data: web::Data<State>,
+    _: Authorization,
+) -> Result<String> {
     log::info!("Heartbeat from worker {}", heartbeat.id);
+    let mut workers = data.workers.lock().unwrap();
+    for w in workers.iter_mut() {
+        if w.id == heartbeat.id {
+            w.last_heartbeat = Some(Utc::now().timestamp());
+        }
+    }
     Ok(format!("Heartbeat from worker {}", heartbeat.id))
 }
 
@@ -181,6 +209,18 @@ async fn main() -> std::io::Result<()> {
 
     let state = web::Data::new(State::new());
 
+    let s = state.clone();
+    tokio::spawn(async move {
+        loop {
+            tokio::time::sleep(Duration::from_secs(10)).await;
+            let mut workers = s.workers.lock().unwrap();
+            workers.retain(|w| match w.last_heartbeat {
+                None => true,
+                Some(t) => Utc::now().timestamp() - t < 60,
+            })
+        }
+    });
+
     HttpServer::new(move || {
         App::new()
             .wrap(Logger::default())
@@ -264,8 +304,8 @@ mod tests {
             FetchResponse::Nop => {
                 panic!("did not expect FetchResponse::Nop")
             }
-            FetchResponse::StopWorking => {
-                panic!("did not expect FetchResponse::NotWorking")
+            FetchResponse::Terminate(w) => {
+                panic!("did not expect FetchResponse::Terminate from worker {}", w)
             }
             FetchResponse::Jobs(new_jobs) => {
                 assert_eq!(new_jobs[0].id, 0);
@@ -288,7 +328,7 @@ mod tests {
                     jobs: Mutex::new(vec![Job {
                         id: 1,
                         cmd: cmd.clone(),
-                        status: Status::Running,
+                        status: Status::Running(0),
                     }]),
                 }))
                 .service(status),
@@ -317,7 +357,7 @@ mod tests {
             .set_json(vec![Update {
                 worker: 0,
                 job: 0,
-                status: Status::Running,
+                status: Status::Running(0),
             }])
             .uri("/update")
             .to_request();
@@ -339,7 +379,7 @@ mod tests {
             .set_json(vec![Job {
                 id: 0,
                 cmd: String::from("hi"),
-                status: Status::Running,
+                status: Status::Running(0),
             }])
             .uri("/submit")
             .to_request();

zoidberg_server/src/webpage.rs

@@ -1,3 +1,4 @@
+use chrono::Utc;
 use zoidberg_lib::types::{Job, Worker};
 
 // TODO: write nicer frontend
@@ -17,10 +18,17 @@ pub fn render(jobs: &[Job], workers: &[Worker]) -> String {
         + "</tbody></table>";
 
     let workers_html: String = String::from("<table class=\"table is-hoverable\">")
-        + "<thead><tr><th><td>ID</td></th></tr></thead><tbody>"
+        + "<thead><tr><th><td>ID</td><td>last heartbeat</td></th></tr></thead><tbody>"
         + &workers
             .iter()
-            .map(|w| format!("<tr><th></th><td>{}</td></tr>", w.id))
+            .map(|w| {
+                let ts = if let Some(ts) = w.last_heartbeat {
+                    format!("{}", Utc::now().timestamp() - ts)
+                } else {
+                    String::from("")
+                };
+                format!("<tr><th></th><td>{}</td><td>{}</td></tr>", w.id, ts)
+            })
             .collect::<Vec<String>>()
             .join("\n")
         + "</tbody></table>";
@@ -43,7 +51,8 @@ pub fn render(jobs: &[Job], workers: &[Worker]) -> String {
   <head>
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
-    <title>Hello Bulma!</title>
+    <title>Zoidberg</title>
+    <link rel="icon" href="data:,">
     <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bulma@0.9.4/css/bulma.min.css">
     {}
   </head>