add support for callback on init in the runner.

gg-broadcast/src/main.rs

@@ -42,7 +42,7 @@ fn main() {
         tx.send(msg).unwrap();
     });
 
-    runner.run(rx);
+    runner.run(rx, None);
     let _ = i.join();
     let _ = g.join();
 }

gg-echo/src/main.rs

@@ -39,6 +39,6 @@ fn main() {
 
     let runner = Runner::new(node, out);
 
-    runner.run(rx);
+    runner.run(rx, None);
     i.join().unwrap();
 }

gg-g_counter/src/main.rs

@@ -1,8 +1,4 @@
-use std::{
-    sync::{Arc, Mutex},
-    thread,
-    time::Duration,
-};
+use std::sync::{Arc, Mutex};
 
 use nebkor_maelstrom::{mk_payload, mk_stdin, Body, Message, Node, Runner};
 
@@ -14,19 +10,22 @@ fn main() {
 
     let runner = Runner::new(node, out);
 
-    let (i, extra_input, rx) = mk_stdin();
-    let init = thread::spawn(move || {
-        thread::sleep(Duration::from_millis(10));
-        extra_input
-            .send(Message {
-                body: Body::from_type("kv_init"),
-                ..Default::default()
-            })
-            .unwrap();
-    });
+    let (i, _, rx) = mk_stdin();
 
-    runner.run(rx);
-    init.join().unwrap();
+    let on_init = |rnr: &Runner| {
+        let payload = mk_payload(&[
+            ("key", KEY.into()),
+            ("from", 0i64.into()),
+            ("to", 0i64.into()),
+            ("create_if_not_exists", true.into()),
+        ]);
+        let body = Body::from_type("cas").with_payload(payload);
+        rnr.send("seq-kv", body);
+    };
+
+    let on_init = Box::new(on_init);
+
+    runner.run(rx, Some(on_init));
     i.join().unwrap();
 }
 
@@ -42,16 +41,6 @@ impl Node for Counter {
         let msg_id = req.body.msg_id.to_owned();
 
         match typ {
-            "kv_init" => {
-                let payload = mk_payload(&[
-                    ("key", KEY.into()),
-                    ("from", 0i64.into()),
-                    ("to", 0i64.into()),
-                    ("create_if_not_exists", true.into()),
-                ]);
-                let body = Body::from_type("cas").with_payload(payload);
-                runner.send("seq-kv", body);
-            }
             "add" => {
                 runner.reply(&req, Body::from_type("add_ok"));
             }

gg-uid/src/main.rs

@@ -26,7 +26,7 @@ fn main() {
 
     let runner = Runner::new(node, out);
 
-    runner.run(rx);
+    runner.run(rx, None);
     i.join().unwrap();
 }
 

nebkor-maelstrom/src/lib.rs

@@ -17,6 +17,7 @@ pub mod kv;
 
 pub type DynNode = Arc<Mutex<dyn Node>>;
 pub type Handler = Box<dyn FnMut(Message)>;
+pub type OnInit = Box<dyn Fn(&Runner)>;
 
 pub trait Node {
     fn handle(&mut self, runner: &Runner, msg: Message);
@@ -46,13 +47,16 @@ impl Runner {
         }
     }
 
-    pub fn run(&self, input: Receiver<Message>) {
+    pub fn run(&self, input: Receiver<Message>, on_init: Option<OnInit>) {
         for msg in input.iter() {
             let typ = &msg.body.typ;
             if let "init" = typ.as_str() {
                 self.init(&msg);
                 let body = Body::from_type("init_ok");
                 self.reply(&msg, body);
+                if let Some(ref h) = on_init {
+                    h(self);
+                }
             } else {
                 let irt = msg.body.in_reply_to;
                 {