refactor: extract iroh wire helpers

crates/geth-node/src/wire.rs

@@ -0,0 +1,49 @@
+//! Shared Iroh stream helpers.
+
+use crate::NodeError;
+
+pub(crate) async fn read_iroh_line(
+    recv: &mut iroh::endpoint::RecvStream,
+    max_len: usize,
+) -> Result<String, NodeError> {
+    let mut bytes = Vec::new();
+    let mut byte = [0_u8; 1];
+    loop {
+        if bytes.len() >= max_len {
+            return Err(NodeError::IrohPeer(format!(
+                "iroh response line exceeded {max_len} bytes"
+            )));
+        }
+        let Some(n) = recv
+            .read(&mut byte)
+            .await
+            .map_err(|error| NodeError::IrohPeer(error.to_string()))?
+        else {
+            if bytes.is_empty() {
+                return Err(NodeError::IrohPeer(
+                    "iroh stream closed before response line".to_owned(),
+                ));
+            }
+            break;
+        };
+        if n == 0 {
+            continue;
+        }
+        bytes.push(byte[0]);
+        if byte[0] == b'\n' {
+            break;
+        }
+    }
+    String::from_utf8(bytes).map_err(|error| NodeError::IrohPeer(error.to_string()))
+}
+
+pub(crate) async fn finish_iroh_send(
+    send: &mut iroh::endpoint::SendStream,
+) -> Result<(), NodeError> {
+    send.finish()
+        .map_err(|error| NodeError::IrohPeer(error.to_string()))?;
+    send.stopped()
+        .await
+        .map_err(|error| NodeError::IrohPeer(error.to_string()))?;
+    Ok(())
+}