wallet can now optionally spend zero-confirmation txs (#188)

* wallet can now optionally spend zero-confirmation txs
* add rule to get_mineable_transactions based on total pool size

pool/src/graph.rs

@@ -260,6 +260,20 @@ impl DirectedGraph {
 	pub fn get_roots(&self) -> Vec<core::hash::Hash> {
 		self.roots.iter().map(|x| x.transaction_hash).collect()
 	}
+
+	/// Get list of all vertices in this graph including the roots
+	pub fn get_vertices(&self) -> Vec<core::hash::Hash> {
+		let mut hashes = self.roots
+			.iter()
+			.map(|x| x.transaction_hash)
+			.collect::<Vec<_>>();
+		let non_root_hashes = self.vertices
+			.iter()
+			.map(|x| x.transaction_hash)
+			.collect::<Vec<_>>();
+		hashes.extend(&non_root_hashes);
+		return hashes
+	}
 }
 
 /// Using transaction merkle_inputs_outputs to calculate a deterministic hash;

pool/src/types.rs

@@ -304,11 +304,17 @@ impl Pool {
 		}
 	}
 
-	/// Simplest possible implementation: just return the roots
+	/// Currently a single rule for miner preference -
+	/// return all txs if less than num_to_fetch txs in the entire pool
+	/// otherwise return num_to_fetch of just the roots
 	pub fn get_mineable_transactions(&self, num_to_fetch: u32) -> Vec<hash::Hash> {
-		let mut roots = self.graph.get_roots();
+		if self.graph.len_vertices() <= num_to_fetch as usize {
-		roots.truncate(num_to_fetch as usize);
+			self.graph.get_vertices()
-		roots
+		} else {
+			let mut roots = self.graph.get_roots();
+			roots.truncate(num_to_fetch as usize);
+			roots
+		}
 	}
 }
 

src/bin/grin.rs

@@ -200,6 +200,12 @@ fn main() {
 			.arg(Arg::with_name("amount")
 				.help("Amount to send in the smallest denomination")
 				.index(1))
+			.arg(Arg::with_name("minimum_confirmations")
+				.help("Minimum number of confirmations required for an output to be spendable.")
+				.short("c")
+				.long("min_conf")
+				.default_value("1")
+				.takes_value(true))
 			.arg(Arg::with_name("dest")
 				.help("Send the transaction to the provided server")
 				.short("d")
@@ -212,7 +218,13 @@ fn main() {
 				transactions.")
 			.arg(Arg::with_name("amount")
 				.help("Amount to burn in the smallest denomination")
-				.index(1)))
+				.index(1))
+			.arg(Arg::with_name("minimum_confirmations")
+				.help("Minimum number of confirmations required for an output to be spendable.")
+				.short("c")
+				.long("min_conf")
+				.default_value("1")
+				.takes_value(true)))
 
 		.subcommand(SubCommand::with_name("info")
 			.about("basic wallet info (outputs)")))
@@ -380,11 +392,22 @@ fn wallet_command(wallet_args: &ArgMatches) {
 				.expect("Amount to send required")
 				.parse()
 				.expect("Could not parse amount as a whole number.");
+			let minimum_confirmations: u64 = send_args
+				.value_of("minimum_confirmations")
+				.unwrap_or("1")
+				.parse()
+				.expect("Could not parse minimum_confirmations as a whole number.");
 			let mut dest = "stdout";
 			if let Some(d) = send_args.value_of("dest") {
 				dest = d;
 			}
-			wallet::issue_send_tx(&wallet_config, &keychain, amount, dest.to_string()).unwrap();
+			wallet::issue_send_tx(
+				&wallet_config,
+				&keychain,
+				amount,
+				minimum_confirmations,
+				dest.to_string()
+			).unwrap();
 		}
 		("burn", Some(send_args)) => {
 			let amount = send_args
@@ -392,7 +415,17 @@ fn wallet_command(wallet_args: &ArgMatches) {
 				.expect("Amount to burn required")
 				.parse()
 				.expect("Could not parse amount as a whole number.");
-			wallet::issue_burn_tx(&wallet_config, &keychain, amount).unwrap();
+			let minimum_confirmations: u64 = send_args
+				.value_of("minimum_confirmations")
+				.unwrap_or("1")
+				.parse()
+				.expect("Could not parse minimum_confirmations as a whole number.");
+			wallet::issue_burn_tx(
+				&wallet_config,
+				&keychain,
+				amount,
+				minimum_confirmations,
+			).unwrap();
 		}
 		("info", Some(_)) => {
 			wallet::show_info(&wallet_config, &keychain);

wallet/src/checker.rs

@@ -20,16 +20,12 @@ use types::*;
 use keychain::Keychain;
 use util;
 
-fn refresh_output(out: &mut OutputData, api_out: Option<api::Output>, tip: &api::Tip) {
+fn refresh_output(out: &mut OutputData, api_out: Option<api::Output>) {
 	if let Some(api_out) = api_out {
 		out.height = api_out.height;
 		out.lock_height = api_out.lock_height;
 
-		if out.status == OutputStatus::Locked {
+		if out.status != OutputStatus::Locked {
-			// leave it Locked locally for now
-		} else if api_out.lock_height > tip.height {
-			out.status = OutputStatus::Immature;
-		} else {
 			out.status = OutputStatus::Unspent;
 		}
 	} else if vec![OutputStatus::Unspent, OutputStatus::Locked].contains(&out.status) {
@@ -39,9 +35,10 @@ fn refresh_output(out: &mut OutputData, api_out: Option<api::Output>, tip: &api:
 
 /// Goes through the list of outputs that haven't been spent yet and check
 /// with a node whether their status has changed.
-pub fn refresh_outputs(config: &WalletConfig, keychain: &Keychain) -> Result<(), Error> {
+pub fn refresh_outputs(
-	let tip = get_tip_from_node(config)?;
+	config: &WalletConfig,
-
+	keychain: &Keychain,
+) -> Result<(), Error> {
 	WalletData::with_wallet(&config.data_file_dir, |wallet_data| {
 		// check each output that's not spent
 		for mut out in wallet_data.outputs.values_mut().filter(|out| {
@@ -50,7 +47,7 @@ pub fn refresh_outputs(config: &WalletConfig, keychain: &Keychain) -> Result<(),
 		{
 			// TODO check the pool for unconfirmed
 			match get_output_from_node(config, keychain, out.value, out.n_child) {
-				Ok(api_out) => refresh_output(&mut out, api_out, &tip),
+				Ok(api_out) => refresh_output(&mut out, api_out),
 				Err(_) => {
 					// TODO find error with connection and return
 					// error!(LOGGER, "Error contacting server node at {}. Is it running?",

wallet/src/info.rs

@@ -23,8 +23,23 @@ pub fn show_info(config: &WalletConfig, keychain: &Keychain) {
 	// operate within a lock on wallet data
 	let _ = WalletData::with_wallet(&config.data_file_dir, |wallet_data| {
 
+		// get the current height via the api
+		// if we cannot get the current height use the max height known to the wallet
+		let current_height = match checker::get_tip_from_node(config) {
+			Ok(tip) => tip.height,
+			Err(_) => {
+				match wallet_data.outputs.values().map(|out| out.height).max() {
+					Some(height) => height,
+					None => 0,
+				}
+			}
+		};
+
+		// need to specify a default value here somehow
+		let minimum_confirmations = 1;
+
 		println!("Outputs - ");
-		println!("key_id, height, lock_height, status, zero_ok, value");
+		println!("key_id, height, lock_height, status, spendable?, coinbase?, value");
 		println!("----------------------------------");
 
 		let mut outputs = wallet_data
@@ -35,13 +50,14 @@ pub fn show_info(config: &WalletConfig, keychain: &Keychain) {
 		outputs.sort_by_key(|out| out.n_child);
 		for out in outputs {
 			println!(
-				"{}, {}, {}, {:?}, {}, {}",
+				"{}, {}, {}, {:?}, {}, {}, {}",
 				out.key_id,
 				out.height,
 				out.lock_height,
 				out.status,
-				out.zero_ok,
+				out.eligible_to_spend(current_height, minimum_confirmations),
-				out.value
+				out.is_coinbase,
+				out.value,
 			);
 		}
 	});

wallet/src/receiver.rs

@@ -172,10 +172,11 @@ impl ApiEndpoint for WalletReceiver {
 }
 
 /// Build a coinbase output and the corresponding kernel
-fn receive_coinbase(config: &WalletConfig,
+fn receive_coinbase(
-                    keychain: &Keychain,
+	config: &WalletConfig,
-                    block_fees: &BlockFees)
+	keychain: &Keychain,
-                    -> Result<(Output, TxKernel, BlockFees), Error> {
+	block_fees: &BlockFees
+) -> Result<(Output, TxKernel, BlockFees), Error> {
 	let root_key_id = keychain.root_key_id();
 
 	// operate within a lock on wallet data
@@ -205,7 +206,7 @@ fn receive_coinbase(config: &WalletConfig,
 			status: OutputStatus::Unconfirmed,
 			height: 0,
 			lock_height: 0,
-			zero_ok: false,
+			is_coinbase: true,
 		});
 
 		debug!(
@@ -280,7 +281,7 @@ fn receive_transaction(
 			status: OutputStatus::Unconfirmed,
 			height: 0,
 			lock_height: 0,
-			zero_ok: false,
+			is_coinbase: false,
 		});
 		debug!(
 			LOGGER,

wallet/src/sender.rs

@@ -31,14 +31,25 @@ pub fn issue_send_tx(
 	config: &WalletConfig,
 	keychain: &Keychain,
 	amount: u64,
+	minimum_confirmations: u64,
 	dest: String,
 ) -> Result<(), Error> {
 	checker::refresh_outputs(config, keychain)?;
 
 	let chain_tip = checker::get_tip_from_node(config)?;
+	let current_height = chain_tip.height;
+
+	// proof of concept - set lock_height on the tx
 	let lock_height = chain_tip.height;
 
-	let (tx, blind_sum) = build_send_tx(config, keychain, amount, lock_height)?;
+	let (tx, blind_sum) = build_send_tx(
+		config,
+		keychain,
+		amount,
+		current_height,
+		minimum_confirmations,
+		lock_height,
+	)?;
 	let json_tx = partial_tx_to_json(amount, blind_sum, tx);
 
 	if dest == "stdout" {
@@ -64,6 +75,8 @@ fn build_send_tx(
 	config: &WalletConfig,
 	keychain: &Keychain,
 	amount: u64,
+	current_height: u64,
+	minimum_confirmations: u64,
 	lock_height: u64,
 ) -> Result<(Transaction, BlindingFactor), Error> {
 	let key_id = keychain.clone().root_key_id();
@@ -71,8 +84,8 @@ fn build_send_tx(
 	// operate within a lock on wallet data
 	WalletData::with_wallet(&config.data_file_dir, |wallet_data| {
 
-		// select some suitable outputs to spend from our local wallet
+		// select some spendable coins from our local wallet
-		let (coins, _) = wallet_data.select(key_id.clone(), u64::max_value());
+		let coins = wallet_data.select(key_id.clone(), current_height, minimum_confirmations);
 
 		// build transaction skeleton with inputs and change
 		// TODO - should probably also check we are sending enough to cover the fees + non-zero output
@@ -89,9 +102,17 @@ fn build_send_tx(
 	})?
 }
 
-pub fn issue_burn_tx(config: &WalletConfig, keychain: &Keychain, amount: u64) -> Result<(), Error> {
+pub fn issue_burn_tx(
+	config: &WalletConfig,
+	keychain: &Keychain,
+	amount: u64,
+	minimum_confirmations: u64,
+) -> Result<(), Error> {
 	let keychain = &Keychain::burn_enabled(keychain, &Identifier::zero());
 
+	let chain_tip = checker::get_tip_from_node(config)?;
+	let current_height = chain_tip.height;
+
 	let _ = checker::refresh_outputs(config, keychain);
 
 	let key_id = keychain.root_key_id();
@@ -99,8 +120,8 @@ pub fn issue_burn_tx(config: &WalletConfig, keychain: &Keychain, amount: u64) ->
 	// operate within a lock on wallet data
 	WalletData::with_wallet(&config.data_file_dir, |mut wallet_data| {
 
-		// select all suitable outputs by passing largest amount
+		// select some spendable coins from the wallet
-		let (coins, _) = wallet_data.select(key_id.clone(), u64::max_value());
+		let coins = wallet_data.select(key_id.clone(), current_height, minimum_confirmations);
 
 		// build transaction skeleton with inputs and change
 		let mut parts = inputs_and_change(&coins, keychain, key_id, &mut wallet_data, amount)?;
@@ -170,7 +191,7 @@ fn inputs_and_change(
 		status: OutputStatus::Unconfirmed,
 		height: 0,
 		lock_height: 0,
-		zero_ok: true,
+		is_coinbase: false,
 	});
 
 	// now lock the ouputs we're spending so we avoid accidental double spend attempt

wallet/src/types.rs

@@ -132,7 +132,6 @@ impl Default for WalletConfig {
 pub enum OutputStatus {
 	Unconfirmed,
 	Unspent,
-	Immature,
 	Locked,
 	Spent,
 }
@@ -142,7 +141,6 @@ impl fmt::Display for OutputStatus {
 		match *self {
 			OutputStatus::Unconfirmed => write!(f, "Unconfirmed"),
 			OutputStatus::Unspent => write!(f, "Unspent"),
-			OutputStatus::Immature => write!(f, "Immature"),
 			OutputStatus::Locked => write!(f, "Locked"),
 			OutputStatus::Spent => write!(f, "Spent"),
 		}
@@ -168,8 +166,8 @@ pub struct OutputData {
 	pub height: u64,
 	/// Height we are locked until
 	pub lock_height: u64,
-	/// Can we spend with zero confirmations? (Did it originate from us, change output etc.)
+	/// Is this a coinbase output? Is it subject to coinbase locktime?
-	pub zero_ok: bool,
+	pub is_coinbase: bool,
 }
 
 impl OutputData {
@@ -177,6 +175,29 @@ impl OutputData {
 	fn lock(&mut self) {
 		self.status = OutputStatus::Locked;
 	}
+
+	pub fn eligible_to_spend(
+		&self,
+		current_height: u64,
+		minimum_confirmations: u64
+	) -> bool {
+		if [
+			OutputStatus::Spent,
+			OutputStatus::Locked,
+		].contains(&self.status) {
+			return false;
+		} else if self.status == OutputStatus::Unconfirmed && self.is_coinbase {
+			return false;
+		} else if self.lock_height > current_height {
+			return false;
+		} else if self.status == OutputStatus::Unspent && self.height + minimum_confirmations <= current_height {
+			return true;
+		} else if self.status == OutputStatus::Unconfirmed && minimum_confirmations == 0 {
+			return true;
+		} else {
+			return false;
+		}
+	}
 }
 
 /// Wallet information tracking all our outputs. Based on HD derivation and
@@ -313,27 +334,22 @@ impl WalletData {
 		self.outputs.get(&key_id.to_hex())
 	}
 
-	/// Select a subset of unspent outputs to spend in a transaction
+	/// Select spendable coins from the wallet
-	/// transferring the provided amount.
+	pub fn select(
-	pub fn select(&self, root_key_id: keychain::Identifier, amount: u64) -> (Vec<OutputData>, i64) {
+		&self,
-		let mut to_spend = vec![];
+		root_key_id: keychain::Identifier,
-		let mut input_total = 0;
+		current_height: u64,
+		minimum_confirmations: u64,
+	) -> Vec<OutputData> {
 
-		for out in self.outputs.values() {
+		self.outputs
-			if out.root_key_id == root_key_id
+			.values()
-				&& (out.status == OutputStatus::Unspent)
+			.filter(|out| {
-					// the following will let us spend zero confirmation change outputs
+				out.root_key_id == root_key_id
-					// || (out.status == OutputStatus::Unconfirmed && out.zero_ok))
+					&& out.eligible_to_spend(current_height, minimum_confirmations)
-			{
+			})
-				to_spend.push(out.clone());
+			.map(|out| out.clone())
-				input_total += out.value;
+			.collect()
-				if input_total >= amount {
-					break;
-				}
-			}
-		}
-		// TODO - clean up our handling of i64 vs u64 so we are consistent
-		(to_spend, (input_total as i64) - (amount as i64))
 	}
 
 	/// Next child index when we want to create a new output.