f - Use a timeout with block_on to prevent deadlock

Test read_chunked_message_body sometimes hangs trying to read within
block_on. AFAICT, the server reads an EOF and drops the stream so never
writes anything for the client to read. Using a timeout triggers a retry
 which seems to resolve the problem.

Author: jkczyz

lightning-block-sync/Cargo.toml

@@ -15,7 +15,7 @@ rpc-client = [ "serde_json", "chunked_transfer" ]
 [dependencies]
 bitcoin = "0.24"
 lightning = { version = "0.0.12", path = "../lightning" }
-tokio = { version = ">=0.2.12", features = [ "tcp", "io-util", "dns" ], optional = true }
+tokio = { version = ">=0.2.12", features = [ "tcp", "io-util", "dns", "time" ], optional = true }
 serde_json = { version = "1", optional = true }
 chunked_transfer = { version = "1.3.0", optional = true }
 futures = { version = "0.3.8" }

lightning-block-sync/src/http.rs

@@ -367,7 +367,11 @@ struct ReadAdapter<'a, R: tokio::io::AsyncRead + std::marker::Unpin>(&'a mut R);
 #[cfg(feature = "tokio")]
 impl<'a, R: tokio::io::AsyncRead + std::marker::Unpin> std::io::Read for ReadAdapter<'a, R> {
 	fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
-		futures::executor::block_on(self.0.read(buf))
+		let read_with_timeout = tokio::time::timeout(Duration::from_secs(2), self.0.read(buf));
+		match futures::executor::block_on(read_with_timeout) {
+			Ok(result) => result,
+			Err(e) => Err(std::io::Error::new(std::io::ErrorKind::TimedOut, e)),
+		}
 	}
 }