From 67a84aa3b6b4d90c860fa01399082007e48bd4f8 Mon Sep 17 00:00:00 2001
From: Joe Ardent <code@ardent.nebcorp.com>
Date: Sun, 9 Jun 2024 13:16:44 -0700
Subject: [PATCH] passes 6b, unreliably gossips writes

---
 gg-txn/src/main.rs | 32 ++++++++++++++++++++++++++++----
 1 file changed, 28 insertions(+), 4 deletions(-)

diff --git a/gg-txn/src/main.rs b/gg-txn/src/main.rs
index b751400..86e4594 100644
--- a/gg-txn/src/main.rs
+++ b/gg-txn/src/main.rs
@@ -41,8 +41,9 @@ struct TANode {
 }
 
 impl TANode {
-    fn transact(&mut self, txn: &Txn) -> Txn {
+    fn transact(&mut self, txn: &Txn) -> (Txn, Txn) {
         let mut out = Txn::with_capacity(txn.len());
+        let mut yo = Txn::new();
         for txn_op in txn.iter() {
             let op = txn_op.op.as_str();
             match op {
@@ -57,6 +58,7 @@ impl TANode {
                 }
                 "w" => {
                     self.store.insert(txn_op.key, txn_op.value.unwrap());
+                    yo.push(txn_op.clone());
                     out.push(txn_op.clone());
                 }
                 _ => {
@@ -65,7 +67,13 @@ impl TANode {
             }
         }
 
-        out
+        (out, yo)
+    }
+
+    fn handle_yo(&mut self, txn: &Txn) {
+        for op in txn.iter() {
+            self.store.insert(op.key, op.value.unwrap());
+        }
     }
 }
 
@@ -77,12 +85,17 @@ impl Node for TANode {
             "txn" => {
                 let txn = get_txn(&msg);
 
-                let txn = self.transact(&txn);
-
+                let (txn, yo) = self.transact(&txn);
+                gossip(runner, &yo);
                 let payload = mk_payload(&[("txn", txn.serialize())]);
                 let body = Body::from_type("txn_ok").with_payload(payload);
                 runner.reply(&msg, body);
             }
+
+            "yo" => {
+                let txn = get_txn(&msg);
+                self.handle_yo(&txn);
+            }
             _ => {
                 eprintln!("unknown message type {typ}")
             }
@@ -90,6 +103,17 @@ impl Node for TANode {
     }
 }
 
+fn gossip(runner: &Runner, goss: &Txn) {
+    let payload = mk_payload(&[("txn", goss.serialize())]);
+    let body = Body::from_type("yo").with_payload(payload);
+
+    let slf = runner.node_id();
+    let nodes = runner.nodes().iter().filter(|e| e.as_str() != slf);
+    for node in nodes {
+        runner.send(node, body.clone());
+    }
+}
+
 fn get_txn(msg: &Message) -> Txn {
     msg.body
         .payload