echo_failure/
echo_failure.rs

1/// ```bash
2/// $ cargo build --examples
3/// $ maelstrom test -w echo --bin ./target/debug/examples/echo_failure --node-count 1 --time-limit 10 --log-stderr
4/// ````
5use async_trait::async_trait;
6use maelstrom::protocol::{ErrorMessageBody, Message};
7use maelstrom::{done, Node, Result, Runtime};
8use serde_json::{Map, Value};
9use std::sync::atomic::Ordering;
10use std::sync::Arc;
11
12pub(crate) fn main() -> Result<()> {
13    Runtime::init(try_main())
14}
15
16async fn try_main() -> Result<()> {
17    let handler = Arc::new(Handler::default());
18    Runtime::new().with_handler(handler).run().await
19}
20
21#[derive(Clone, Default)]
22struct Handler {
23    inter: Arc<std::sync::atomic::AtomicI32>,
24}
25
26#[async_trait]
27impl Node for Handler {
28    async fn process(&self, runtime: Runtime, message: Message) -> Result<()> {
29        if message.get_type() == "echo" {
30            if self.inter.fetch_add(1, Ordering::SeqCst) > 0 {
31                let err = maelstrom::Error::TemporarilyUnavailable {};
32                let body = ErrorMessageBody::from_error(err);
33                return runtime.reply(message, body).await;
34            }
35
36            let echo = format!("Another echo {}", message.body.msg_id);
37            let msg = Value::Object(Map::from_iter([("echo".to_string(), Value::String(echo))]));
38            return runtime.reply(message, msg).await;
39        }
40
41        done(runtime, message)
42    }
43}
44
45// Putting `#[serde(rename = "type")] typo: String` is not necessary,
46// as it is auto-deducted.
47// #[derive(Serialize)]
48// struct EchoResponse {
49//     echo: String,
50// }
echo_failure/echo_failure.rs

echo_failure/
echo_failure.rs
