fix: handle connection reset

Signed-off-by: Christina Sørensen <christina@cafkafk.com>

src/main.rs

@@ -88,26 +88,46 @@ mod nix {
 }
 
 mod net {
-    use std::net::SocketAddr;
+    use std::{net::SocketAddr, time::Duration};
 
     use reqwest::{StatusCode, ClientBuilder, Client};
     use async_recursion::async_recursion;
+    use tokio::time::sleep;
 
     #[async_recursion]
-    pub async fn nar_exists(client: Client, domain: &str, hash: &str) -> usize {
+    pub async fn nar_exists(client: Client, domain: &str, hash: &str, slide: u64) -> usize {
         let response = client
-            .get(format!("https://{domain}/{hash}.narinfo"))
+            .head(format!("https://{domain}/{hash}.narinfo"))
             .send()
-            .await
+            .await;
-            .unwrap();
 
-        match response.status().as_u16() {
+        match response {
-            200 => 1,
+            Ok(response) if response.status().as_u16() == 200 => 1,
-            // Retry on ConnectionReset
+            Ok(response) if response.status().as_u16() == 404 => 0,
-            104 => nar_exists(client, domain, hash).await,
+            _ => {
-            _ => 0
+                // We're so fast now we get rate limited.
+                //
+                // Writng an actual sliding window seems kinda hard,
+                // so we do this instead.
+                sleep(Duration::from_millis(slide)).await;
+                nar_exists(client, domain, hash, slide * 2).await
             }
         }
+
+        // match response.status().as_u16() {
+        //     200 => 1,
+        //     // Retry on ConnectionReset
+        //     104 => {
+        //         // We're so fast now we get rate limited.
+        //         //
+        //         // Writng an actual sliding window seems kinda hard,
+        //         // so we do this instead.
+        //         sleep(Duration::from_millis(slide)).await;
+        //         nar_exists(client, domain, hash, slide * 2).await
+        //     },
+        //     _ => 0
+        // }
+    }
 }
 
 // #[tokio::main(flavor = "multi_thread", worker_threads = 100)]
@@ -129,6 +149,9 @@ async fn main() -> io::Result<()> {
     let binding = get_requisites("DBCAC");
     let connection_buffer = binding.lines().map(|line| line.to_owned()).collect::<Vec<_>>();
 
+    // FIXME make constant
+    let slide = 100;
+
     // FIXME we take ten just for testing
     let tasks = connection_buffer
         .into_iter()
@@ -137,7 +160,7 @@ async fn main() -> io::Result<()> {
             let client = client.clone();
             tokio::spawn(async move {
                 info!("connecting to {domain} {domain_addr:#?} for {hash}");
-                net::nar_exists(client, domain, &hash).await
+                net::nar_exists(client, domain, &hash, slide).await
             })
         })
         .collect_vec();