From 820d55a532ba139da64755a21f140ca298a56425 Mon Sep 17 00:00:00 2001
From: Yeastplume <yeastplume@gmail.com>
Date: Wed, 25 Apr 2018 16:48:19 +0100
Subject: [PATCH] Change wallet retry strategy (and address stratum panic)
 (#1004)

* remove complex retry from wallet client

* remove complex retry from wallet client

* move retry code to stratum
---
 servers/src/mining/mine_block.rs | 10 ++++++++-
 wallet/src/client.rs             | 35 +++++---------------------------
 2 files changed, 14 insertions(+), 31 deletions(-)

diff --git a/servers/src/mining/mine_block.rs b/servers/src/mining/mine_block.rs
index 56a8f1c5b..c822a4727 100644
--- a/servers/src/mining/mine_block.rs
+++ b/servers/src/mining/mine_block.rs
@@ -86,6 +86,7 @@ pub fn get_block(
 	max_tx: u32,
 	wallet_listener_url: Option<String>,
 ) -> (core::Block, BlockFees) {
+	let wallet_retry_interval = 5;
 	// get the latest chain state and build a block on top of it
 	let mut result = build_block(
 		chain,
@@ -102,6 +103,14 @@ pub fn get_block(
 					"Duplicate commit for potential coinbase detected. Trying next derivation."
 				);
 			}
+			self::Error::Wallet(_) => {
+				error!(
+					LOGGER,
+					"Stratum server: Can't connect to wallet listener at {:?}; will retry",
+					wallet_listener_url.as_ref().unwrap()
+				);
+				thread::sleep(Duration::from_secs(wallet_retry_interval));
+			}
 			ae => {
 				warn!(LOGGER, "Error building new block: {:?}. Retrying.", ae);
 			}
@@ -227,7 +236,6 @@ fn get_coinbase(
 			let url = format!("{}/v1/receive/coinbase", wallet_listener_url.as_str());
 
 			let res = wallet::client::create_coinbase(&url, &block_fees)?;
-
 			let out_bin = util::from_hex(res.output).unwrap();
 			let kern_bin = util::from_hex(res.kernel).unwrap();
 			let key_id_bin = util::from_hex(res.key_id).unwrap();
diff --git a/wallet/src/client.rs b/wallet/src/client.rs
index 9ca21cdda..ac715cd45 100644
--- a/wallet/src/client.rs
+++ b/wallet/src/client.rs
@@ -12,17 +12,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use std::time;
-use std::ops::FnMut;
-
 use futures::{Future, Stream};
 use failure::ResultExt;
 use hyper;
 use hyper::{Method, Request};
 use hyper::header::ContentType;
 use tokio_core::reactor;
-use tokio_retry::Retry;
-use tokio_retry::strategy::FibonacciBackoff;
 use serde_json;
 
 use types::*;
@@ -32,36 +27,16 @@ use std::io;
 /// Call the wallet API to create a coinbase output for the given block_fees.
 /// Will retry based on default "retry forever with backoff" behavior.
 pub fn create_coinbase(url: &str, block_fees: &BlockFees) -> Result<CbData, Error> {
-	let mut has_error = false;
-
-	retry_backoff_forever(|| {
-		let res = single_create_coinbase(&url, &block_fees);
-		if let Err(_) = res {
-			has_error = true;
+	match single_create_coinbase(&url, &block_fees) {
+		Err(e) => {
 			error!(
 				LOGGER,
 				"Failed to get coinbase from {}. Run grin wallet listen", url
 			);
+			Err(e)
 		}
-		if has_error {
-			error!(LOGGER, "Successfully received coinbase from {}", url);
-		}
-		res
-	})
-}
-
-/// Runs the specified function wrapped in some basic retry logic.
-fn retry_backoff_forever<F, R>(f: F) -> Result<R, Error>
-where
-	F: FnMut() -> Result<R, Error>,
-{
-	let mut core =
-		reactor::Core::new().context(ErrorKind::GenericError("Could not create reactor"))?;
-	let retry_strategy =
-		FibonacciBackoff::from_millis(100).max_delay(time::Duration::from_secs(10));
-	let retry_future = Retry::spawn(core.handle(), retry_strategy, f);
-	let res = core.run(retry_future).unwrap();
-	Ok(res)
+		Ok(res) => Ok(res),
+	}
 }
 
 pub fn send_partial_tx(url: &str, partial_tx: &PartialTx, fluff: bool) -> Result<PartialTx, Error> {