ensure aborted transactions don't get written

This commit is contained in:
Joe Ardent 2024-06-09 14:11:52 -07:00
parent 64153b7fd4
commit 350d24d284

View file

@ -1,6 +1,6 @@
use std::collections::HashMap;
use nebkor_maelstrom::{mk_payload, Body, Message, Node, Runner};
use nebkor_maelstrom::{mk_payload, Body, ErrorCode, Message, Node, Runner};
use serde_json::Value;
type Txn = Vec<TxnOp>;
@ -44,6 +44,7 @@ impl TANode {
fn transact(&mut self, txn: &Txn) -> (Txn, Txn) {
let mut out = Txn::with_capacity(txn.len());
let mut yo = Txn::new();
let mut new = HashMap::new();
for txn_op in txn.iter() {
let op = txn_op.op.as_str();
match op {
@ -57,7 +58,7 @@ impl TANode {
out.push(op);
}
"w" => {
self.store.insert(txn_op.key, txn_op.value.unwrap());
new.insert(txn_op.key, txn_op.value.unwrap());
yo.push(txn_op.clone());
out.push(txn_op.clone());
}
@ -67,13 +68,13 @@ impl TANode {
}
}
(out, yo)
// if the transaction were aborted, we'd not want to commit it by inserting from
// `new` here
for (k, v) in new.into_iter() {
self.store.insert(k, v);
}
fn handle_yo(&mut self, txn: &Txn) {
for op in txn.iter() {
self.store.insert(op.key, op.value.unwrap());
}
(out, yo)
}
}
@ -86,15 +87,26 @@ impl Node for TANode {
let txn = get_txn(&msg);
let (txn, yo) = self.transact(&txn);
// simulated aborted transaction for G1a-resistance
if txn.is_empty() {
let mut error = Body::from_type("error");
let ec =
ErrorCode::Definite(nebkor_maelstrom::protocol::DefiniteError::TxnConflict);
error.code = Some(ec);
error.text = Some("shit's fucked".into());
runner.reply(&msg, error);
return;
}
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);
for op in txn.iter() {
self.store.insert(op.key, op.value.unwrap());
}
}
_ => {
eprintln!("unknown message type {typ}")