add retry logic to miner when hitting wallet coinbase API (#213)

* mount v2 router for flexibility, wallet checker now refreshes multiple outputs via single api call
* fix the api router
* wallet api handlers, miner uses wallet_client
* retry logic via tokio_retry, miner creates new coinbase output via wallet API (retries several times)
* move wallet client into wallet crateand rework the lock acquisition logic to use tokio_retry

api/src/handlers.rs

@@ -1,4 +1,4 @@
-// Copyright 2016 The Grin Developers
+// Copyright 2017 The Grin Developers
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

grin/Cargo.toml

@@ -19,13 +19,14 @@ secp256k1zkp = { git = "https://github.com/mimblewimble/rust-secp256k1-zkp" }
 
 futures = "^0.1.15"
 futures-cpupool = "^0.1.3"
-hyper = { git = "https://github.com/hyperium/hyper" }
+hyper = "~0.11.4"
 slog = { version = "^2.0.12", features = ["max_level_trace", "release_max_level_trace"] }
 time = "^0.1"
 serde = "~1.0.8"
 serde_derive = "~1.0.8"
-tokio-core="^0.1.1"
-tokio-timer="^0.1.0"
+serde_json = "~1.0.2"
+tokio-core="~0.1.1"
+tokio-timer="~0.1.0"
 rand = "^0.3"
 itertools = "~0.6.0"
 

grin/src/lib.rs

@@ -30,6 +30,7 @@ extern crate rand;
 extern crate serde;
 #[macro_use]
 extern crate serde_derive;
+extern crate serde_json;
 extern crate time;
 extern crate tokio_core;
 extern crate tokio_timer;

grin/src/miner.rs

@@ -17,13 +17,11 @@
 
 use rand::{self, Rng};
 use std::sync::{Arc, RwLock};
-use std::thread;
+use std::{thread, str};
 use std;
-use std::str;
 use time;
 
 use adapters::PoolToChainAdapter;
-use api;
 use core::consensus;
 use core::core;
 use core::core::Proof;
@@ -36,15 +34,15 @@ use pow::types::MinerConfig;
 use core::ser;
 use core::ser::AsFixedBytes;
 use util::LOGGER;
-
-// use core::genesis;
+use types::Error;
 
 use chain;
 use secp;
 use pool;
 use util;
 use keychain::{Identifier, Keychain};
-use wallet::{BlockFees, WalletReceiveRequest, CbData};
+use wallet;
+use wallet::BlockFees;
 
 use pow::plugin::PluginMiner;
 
@@ -566,8 +564,10 @@ impl Miner {
 			height,
 		};
 
-		let (output, kernel, block_fees) = self.get_coinbase(block_fees);
+		// TODO - error handling, things can go wrong with get_coinbase (wallet api down etc.)
+		let (output, kernel, block_fees) = self.get_coinbase(block_fees).unwrap();
 		let mut b = core::Block::with_reward(head, txs, output, kernel).unwrap();
+
 		debug!(
 			LOGGER,
 			"(Server ID: {}) Built new block with {} inputs and {} outputs, difficulty: {}",
@@ -591,26 +591,33 @@ impl Miner {
 		(b, block_fees)
 	}
 
-	fn get_coinbase(&self, block_fees: BlockFees) -> (core::Output, core::TxKernel, BlockFees) {
-		if self.config.burn_reward {
+	///
+	/// Probably only want to do this when testing.
+	///
+	fn burn_reward(
+		&self,
+		block_fees: BlockFees,
+	) -> Result<(core::Output, core::TxKernel, BlockFees), Error> {
 		let keychain = Keychain::from_random_seed().unwrap();
 		let key_id = keychain.derive_key_id(1).unwrap();
-			let (out, kern) = core::Block::reward_output(&keychain, &key_id, block_fees.fees)
+		let (out, kernel) = core::Block::reward_output(&keychain, &key_id, block_fees.fees)
 			.unwrap();
-			(out, kern, block_fees)
+		Ok((out, kernel, block_fees))
+	}
+
+	fn get_coinbase(
+		&self,
+		block_fees: BlockFees,
+	) -> Result<(core::Output, core::TxKernel, BlockFees), Error> {
+		if self.config.burn_reward {
+			self.burn_reward(block_fees)
 		} else {
 			let url = format!(
-				"{}/v1/receive/coinbase",
-				self.config.wallet_receiver_url.as_str()
-			);
-			let request = WalletReceiveRequest::Coinbase(block_fees.clone());
-			let res: CbData = api::client::post(url.as_str(), &request).expect(
-				format!(
-					"(Server ID: {}) Wallet receiver unreachable, could not claim reward. Is it running?",
-					self.debug_output_id
-						.as_str()
-				).as_str(),
-			);
+				"{}/v2/receive/coinbase",
+				self.config.wallet_receiver_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();
@@ -624,7 +631,7 @@ impl Miner {
 
 			debug!(LOGGER, "block_fees here: {:?}", block_fees);
 
-			(output, kernel, block_fees)
+			Ok((output, kernel, block_fees))
 		}
 	}
 }

grin/src/types.rs

@@ -20,6 +20,7 @@ use p2p;
 use pool;
 use store;
 use pow;
+use wallet;
 use core::global::MiningParameterMode;
 
 /// Error type wrapping underlying module errors.
@@ -31,8 +32,10 @@ pub enum Error {
 	Chain(chain::Error),
 	/// Error originating from the peer-to-peer network.
 	P2P(p2p::Error),
-	/// Error originating from HTTP API calls
+	/// Error originating from HTTP API calls.
 	API(api::Error),
+	/// Error originating from wallet API.
+	Wallet(wallet::Error),
 }
 
 impl From<chain::Error> for Error {
@@ -59,6 +62,12 @@ impl From<api::Error> for Error {
 	}
 }
 
+impl From<wallet::Error> for Error {
+	fn from(e: wallet::Error) -> Error {
+		Error::Wallet(e)
+	}
+}
+
 /// Type of seeding the server will use to find other peers on the network.
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 pub enum Seeding {

wallet/Cargo.toml

@@ -16,7 +16,12 @@ blake2-rfc = "~0.2.17"
 serde = "~1.0.8"
 serde_derive = "~1.0.8"
 serde_json = "~1.0.2"
+bodyparser = "~0.7.0"
+futures = "^0.1.15"
 iron = "~0.5.1"
+hyper = "~0.11.4"
+tokio-core="~0.1.1"
+tokio-retry="~0.1.0"
 router = "~0.5.1"
 grin_api = { path = "../api" }
 grin_core = { path = "../core" }

wallet/src/client.rs

@@ -0,0 +1,74 @@
+// Copyright 2017 The Grin Developers
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use std::{io, time};
+use std::ops::FnMut;
+
+use futures::{Future, Stream};
+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::*;
+use util::LOGGER;
+
+/// 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> {
+	retry_backoff_forever(|| {
+		let res = single_create_coinbase(&url, &block_fees);
+		if let Err(_) = res {
+			error!(LOGGER, "Failed to get coinbase via wallet API (will retry)...");
+		}
+		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()?;
+	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)
+}
+
+/// Makes a single request to the wallet API to create a new coinbase output.
+fn single_create_coinbase(url: &str, block_fees: &BlockFees) -> Result<CbData, Error> {
+	let mut core = reactor::Core::new()?;
+	let client = hyper::Client::new(&core.handle());
+
+	let mut req = Request::new(Method::Post, url.parse()?);
+	req.headers_mut().set(ContentType::json());
+	let json = serde_json::to_string(&block_fees)?;
+	req.set_body(json);
+
+	let work = client.request(req).and_then(|res| {
+		res.body().concat2().and_then(move |body| {
+			let coinbase: CbData = serde_json::from_slice(&body)
+				.map_err(|e| {io::Error::new(io::ErrorKind::Other, e)})?;
+			Ok(coinbase)
+		})
+	});
+
+	let res = core.run(work)?;
+	Ok(res)
+}

wallet/src/handlers.rs

@@ -0,0 +1,88 @@
+// Copyright 2017 The Grin Developers
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use iron::prelude::*;
+use iron::Handler;
+use iron::status;
+use serde_json;
+use bodyparser;
+
+use receiver::receive_coinbase;
+use core::ser;
+use api;
+use keychain::Keychain;
+use types::*;
+use util;
+
+
+pub struct CoinbaseHandler {
+	pub config: WalletConfig,
+	pub keychain: Keychain,
+}
+
+impl CoinbaseHandler {
+	fn build_coinbase(&self, block_fees: &BlockFees) -> Result<CbData, Error> {
+		let (out, kern, block_fees) = receive_coinbase(
+			&self.config,
+			&self.keychain,
+			block_fees,
+		).map_err(|e| {
+			api::Error::Internal(format!("Error building coinbase: {:?}", e))
+		})?;
+
+		let out_bin = ser::ser_vec(&out).map_err(|e| {
+			api::Error::Internal(format!("Error serializing output: {:?}", e))
+		})?;
+
+		let kern_bin = ser::ser_vec(&kern).map_err(|e| {
+			api::Error::Internal(format!("Error serializing kernel: {:?}", e))
+		})?;
+
+		let key_id_bin = match block_fees.key_id {
+			Some(key_id) => {
+				ser::ser_vec(&key_id).map_err(|e| {
+					api::Error::Internal(
+						format!("Error serializing kernel: {:?}", e),
+					)
+				})?
+			}
+			None => vec![],
+		};
+
+		Ok(CbData {
+			output: util::to_hex(out_bin),
+			kernel: util::to_hex(kern_bin),
+			key_id: util::to_hex(key_id_bin),
+		})
+	}
+}
+
+// TODO - error handling - what to return if we fail to get the wallet lock for some reason...
+impl Handler for CoinbaseHandler {
+	fn handle(&self, req: &mut Request) -> IronResult<Response> {
+		let struct_body = req.get::<bodyparser::Struct<BlockFees>>();
+
+		if let Ok(Some(block_fees)) = struct_body {
+			let coinbase = self.build_coinbase(&block_fees)
+				.map_err(|e| IronError::new(e, status::BadRequest))?;
+			if let Ok(json) = serde_json::to_string(&coinbase) {
+				Ok(Response::with((status::Ok, json)))
+			} else {
+				Ok(Response::with((status::BadRequest, "")))
+			}
+		} else {
+			Ok(Response::with((status::BadRequest, "")))
+		}
+	}
+}

wallet/src/lib.rs

@@ -1,4 +1,4 @@
-// Copyright 2016 The Grin Developers
+// Copyright 2017 The Grin Developers
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -24,7 +24,13 @@ extern crate serde;
 extern crate serde_derive;
 extern crate serde_json;
 
+extern crate bodyparser;
+extern crate futures;
+extern crate tokio_core;
+extern crate tokio_retry;
+extern crate hyper;
 extern crate iron;
+#[macro_use]
 extern crate router;
 
 extern crate grin_api as api;
@@ -34,13 +40,15 @@ extern crate grin_util as util;
 extern crate secp256k1zkp as secp;
 
 mod checker;
+mod handlers;
 mod info;
 mod receiver;
 mod sender;
 mod types;
+pub mod client;
 pub mod server;
 
 pub use info::show_info;
 pub use receiver::{WalletReceiver, receive_json_tx};
 pub use sender::{issue_send_tx, issue_burn_tx};
-pub use types::{BlockFees, CbData, WalletConfig, WalletReceiveRequest, WalletSeed};
+pub use types::{BlockFees, CbData, Error, WalletConfig, WalletReceiveRequest, WalletSeed};

wallet/src/receiver.rs

@@ -67,10 +67,11 @@ pub struct TxWrapper {
 /// Receive an already well formed JSON transaction issuance and finalize the
 /// transaction, adding our receiving output, to broadcast to the rest of the
 /// network.
-pub fn receive_json_tx(config: &WalletConfig,
+pub fn receive_json_tx(
+	config: &WalletConfig,
 	keychain: &Keychain,
-                       partial_tx_str: &str)
-                       -> Result<(), Error> {
+	partial_tx_str: &str,
+) -> Result<(), Error> {
 	let (amount, blinding, partial_tx) = partial_tx_from_json(keychain, partial_tx_str)?;
 	let final_tx = receive_transaction(config, keychain, amount, blinding, partial_tx)?;
 	let tx_hex = util::to_hex(ser::ser_vec(&final_tx).unwrap());
@@ -96,49 +97,11 @@ impl ApiEndpoint for WalletReceiver {
 	type OP_OUT = CbData;
 
 	fn operations(&self) -> Vec<Operation> {
-		vec![Operation::Custom("coinbase".to_string()),
-		     Operation::Custom("receive_json_tx".to_string())]
+		vec![Operation::Custom("receive_json_tx".to_string())]
 	}
 
 	fn operation(&self, op: String, input: WalletReceiveRequest) -> ApiResult<CbData> {
 		match op.as_str() {
-			"coinbase" => {
-				match input {
-					WalletReceiveRequest::Coinbase(cb_fees) => {
-						debug!(LOGGER, "Operation {} with fees {:?}", op, cb_fees);
-						let (out, kern, block_fees) = receive_coinbase(
-							&self.config,
-							&self.keychain,
-							&cb_fees,
-						).map_err(|e| {
-							api::Error::Internal(format!("Error building coinbase: {:?}", e))
-						})?;
-						let out_bin = ser::ser_vec(&out).map_err(|e| {
-							api::Error::Internal(format!("Error serializing output: {:?}", e))
-						})?;
-						let kern_bin = ser::ser_vec(&kern).map_err(|e| {
-							api::Error::Internal(format!("Error serializing kernel: {:?}", e))
-						})?;
-						let key_id_bin = match block_fees.key_id {
-							Some(key_id) => {
-								ser::ser_vec(&key_id).map_err(|e| {
-									api::Error::Internal(
-										format!("Error serializing kernel: {:?}", e),
-									)
-								})?
-							}
-							None => vec![],
-						};
-
-						Ok(CbData {
-							output: util::to_hex(out_bin),
-							kernel: util::to_hex(kern_bin),
-							key_id: util::to_hex(key_id_bin),
-						})
-					}
-					_ => Err(api::Error::Argument(format!("Incorrect request data: {}", op))),
-				}
-			}
 			"receive_json_tx" => {
 				match input {
 					WalletReceiveRequest::PartialTransaction(partial_tx_str) => {
@@ -202,7 +165,7 @@ fn next_available_key(
 }
 
 /// Build a coinbase output and the corresponding kernel
-fn receive_coinbase(
+pub fn receive_coinbase(
 	config: &WalletConfig,
 	keychain: &Keychain,
 	block_fees: &BlockFees

wallet/src/server.rs

@@ -1,4 +1,4 @@
-// Copyright 2016 The Grin Developers
+// Copyright 2017 The Grin Developers
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,6 +15,7 @@
 
 use api::ApiServer;
 use keychain::Keychain;
+use handlers::CoinbaseHandler;
 use receiver::WalletReceiver;
 use types::WalletConfig;
 use util::LOGGER;
@@ -31,11 +32,23 @@ pub fn start_rest_apis(wallet_config: WalletConfig, keychain: Keychain) {
 	apis.register_endpoint(
 		"/receive".to_string(),
 		WalletReceiver {
-			keychain: keychain,
 			config: wallet_config.clone(),
+			keychain: keychain.clone(),
 		},
 	);
 
+	let coinbase_handler = CoinbaseHandler {
+		config: wallet_config.clone(),
+		keychain: keychain.clone(),
+	};
+	// let tx_handler = TxHandler{};
+
+	let router = router!(
+		receive_coinbase: post "/receive/coinbase" => coinbase_handler,
+		// receive_tx: post "/receive/tx" => tx_handler,
+	);
+	apis.register_handler("/v2", router);
+
 	apis.start(wallet_config.api_http_addr).unwrap_or_else(|e| {
 		error!(LOGGER, "Failed to start Grin wallet receiver: {}.", e);
 	});

wallet/src/types.rs

@@ -1,4 +1,4 @@
-// Copyright 2016 The Grin Developers
+// Copyright 2017 The Grin Developers
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -14,7 +14,7 @@
 
 use blake2;
 use rand::{thread_rng, Rng};
-use std::{fmt, num, thread, time};
+use std::{fmt, num, error};
 use std::convert::From;
 use std::fs::{self, File, OpenOptions};
 use std::io::{self, Read, Write};
@@ -23,8 +23,13 @@ use std::path::MAIN_SEPARATOR;
 use std::collections::HashMap;
 use std::cmp::min;
 
+use hyper;
 use serde_json;
 use secp;
+use tokio_core::reactor;
+use tokio_retry::Retry;
+use tokio_retry::strategy::FibonacciBackoff;
+
 
 use api;
 use core::core::{Transaction, transaction};
@@ -68,6 +73,26 @@ pub enum Error {
 	IOError(io::Error),
 	/// Error when contacting a node through its API
 	Node(api::Error),
+	/// Error originating from hyper.
+	Hyper(hyper::Error),
+	/// Error originating from hyper uri parsing.
+	Uri(hyper::error::UriError),
+}
+
+impl error::Error for Error {
+	fn description(&self) -> &str {
+		match *self {
+			_ => "some kind of wallet error",
+		}
+	}
+}
+
+impl fmt::Display for Error {
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+		match *self {
+			_ => write!(f, "some kind of wallet error"),
+		}
+	}
 }
 
 impl From<keychain::Error> for Error {
@@ -112,6 +137,18 @@ impl From<io::Error> for Error {
 	}
 }
 
+impl From<hyper::Error> for Error {
+	fn from(e: hyper::Error) -> Error {
+		Error::Hyper(e)
+	}
+}
+
+impl From<hyper::error::UriError> for Error {
+	fn from(e: hyper::error::UriError) -> Error {
+		Error::Uri(e)
+	}
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct WalletConfig {
 	// Whether to run a wallet
@@ -361,47 +398,34 @@ impl WalletData {
 		let data_file_path = &format!("{}{}{}", data_file_dir, MAIN_SEPARATOR, DAT_FILE);
 		let lock_file_path = &format!("{}{}{}", data_file_dir, MAIN_SEPARATOR, LOCK_FILE);
 
-		// create the lock file, if it already exists, will produce an error
-		// sleep and retry a few times if we cannot get it the first time
-		let mut retries = 0;
-		loop {
-			let result = OpenOptions::new()
+		info!(LOGGER, "Acquiring wallet lock ...");
+
+		let action = || {
+			debug!(LOGGER, "Attempting to acquire wallet lock");
+			OpenOptions::new()
 				.write(true)
 				.create_new(true)
 				.open(lock_file_path)
-				.map_err(|_| {
-					Error::WalletData(format!(
-						"Could not create wallet lock file. Either \
-						some other process is using the wallet or there is a write access issue."
-					))
-				});
-			match result {
-				Ok(_) => {
-					info!(LOGGER, "acquired wallet lock ...");
-					break;
-				}
-				Err(e) => {
-					if retries >= 10 {
-						info!(
+		};
+
+		// use tokio_retry to cleanly define some retry logic
+		let mut core = reactor::Core::new().unwrap();
+		let retry_strategy = FibonacciBackoff::from_millis(10).take(10);
+		let retry_future = Retry::spawn(core.handle(), retry_strategy, action);
+		let retry_result = core.run(retry_future);
+
+		match retry_result {
+			Ok(_) => {},
+			Err(_) => {
+				error!(
 					LOGGER,
-							"failed to obtain wallet.lock after {} retries, \
-							unable to successfully open the wallet",
-							retries
+					"Failed to acquire wallet lock file (multiple retries)",
 				);
-						return Err(e);
-					}
-					debug!(
-						LOGGER,
-						"failed to obtain wallet.lock, retries - {}, sleeping and retrying",
-						retries
-					);
-					retries += 1;
-					thread::sleep(time::Duration::from_millis(250));
-				}
+				return Err(Error::WalletData(format!("Failed to acquire lock file")));
 			}
 		}
 
-		// do what needs to be done
+		// We successfully acquired the lock - so do what needs to be done.
 		let mut wdat = WalletData::read_or_create(data_file_path)?;
 		let res = f(&mut wdat);
 		wdat.write(data_file_path)?;