// Copyright 2017-2019 Parity Technologies (UK) Ltd. // This file is part of Substrate. // Substrate is free software: you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // Substrate is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // You should have received a copy of the GNU General Public License // along with Substrate. If not, see . //! Substrate service. Starts a thread that spins up the network, client, and extrinsic pool. //! Manages communication between them. #![warn(missing_docs)] mod components; mod chain_spec; pub mod config; pub mod chain_ops; pub mod error; use std::io; use std::net::SocketAddr; use std::collections::HashMap; use futures::sync::mpsc; use parking_lot::Mutex; use client::{BlockchainEvents, backend::Backend}; use exit_future::Signal; use futures::prelude::*; use keystore::Store as Keystore; use log::{info, warn, debug}; use parity_codec::{Encode, Decode}; use primitives::Pair; use runtime_primitives::generic::BlockId; use runtime_primitives::traits::{Header, SaturatedConversion}; use substrate_executor::NativeExecutor; use network::SyncProvider; use sysinfo::{get_current_pid, ProcessExt, System, SystemExt}; use tel::{telemetry, SUBSTRATE_INFO}; pub use self::error::Error; pub use config::{Configuration, Roles, PruningMode}; pub use chain_spec::{ChainSpec, Properties}; pub use transaction_pool::txpool::{ self, Pool as TransactionPool, Options as TransactionPoolOptions, ChainApi, IntoPoolError }; use client::runtime_api::BlockT; pub use client::FinalityNotifications; pub use components::{ServiceFactory, FullBackend, FullExecutor, LightBackend, LightExecutor, Components, PoolApi, ComponentClient, ComponentBlock, FullClient, LightClient, FullComponents, LightComponents, CodeExecutor, NetworkService, FactoryChainSpec, FactoryBlock, FactoryFullConfiguration, RuntimeGenesis, FactoryGenesis, ComponentExHash, ComponentExtrinsic, FactoryExtrinsic }; use components::{StartRPC, MaintainTransactionPool, OffchainWorker}; #[doc(hidden)] pub use std::{ops::Deref, result::Result, sync::Arc}; #[doc(hidden)] pub use network::{FinalityProofProvider, OnDemand}; #[doc(hidden)] pub use tokio::runtime::TaskExecutor; const DEFAULT_PROTOCOL_ID: &str = "sup"; /// Substrate service. pub struct Service { client: Arc>, select_chain: Option<::SelectChain>, network: Option>>, transaction_pool: Arc>, keystore: Keystore, exit: ::exit_future::Exit, signal: Option, /// Configuration of this Service pub config: FactoryFullConfiguration, _rpc: Box, _telemetry: Option, _offchain_workers: Option, ComponentBlock>>>, _telemetry_on_connect_sinks: Arc>>>, } /// Creates bare client without any networking. pub fn new_client(config: &FactoryFullConfiguration) -> Result>>, error::Error> { let executor = NativeExecutor::new(config.default_heap_pages); let (client, _) = components::FullComponents::::build_client( config, executor, )?; Ok(client) } /// Stream of events for connection established to a telemetry server. pub type TelemetryOnConnectNotifications = mpsc::UnboundedReceiver<()>; /// Used to hook on telemetry connection established events. pub struct TelemetryOnConnect<'a> { /// Handle to a future that will resolve on exit. pub on_exit: Box + Send + 'static>, /// Event stream. pub telemetry_connection_sinks: TelemetryOnConnectNotifications, /// Executor to which the hook is spawned. pub executor: &'a TaskExecutor, } impl Service { /// Get event stream for telemetry connection established events. pub fn telemetry_on_connect_stream(&self) -> TelemetryOnConnectNotifications { let (sink, stream) = mpsc::unbounded(); self._telemetry_on_connect_sinks.lock().push(sink); stream } /// Creates a new service. pub fn new( mut config: FactoryFullConfiguration, task_executor: TaskExecutor, ) -> Result { let (signal, exit) = ::exit_future::signal(); // Create client let executor = NativeExecutor::new(config.default_heap_pages); let mut keystore = Keystore::open(config.keystore_path.as_str().into())?; // This is meant to be for testing only // FIXME #1063 remove this for seed in &config.keys { keystore.generate_from_seed(seed)?; } // Keep the public key for telemetry let public_key = match keystore.contents()?.get(0) { Some(public_key) => public_key.clone(), None => { let key = keystore.generate(&config.password)?; let public_key = key.public(); info!("Generated a new keypair: {:?}", public_key); public_key } }; let (client, on_demand) = Components::build_client(&config, executor)?; let select_chain = Components::build_select_chain(&mut config, client.clone())?; let import_queue = Box::new(Components::build_import_queue( &mut config, client.clone(), select_chain.clone(), )?); let finality_proof_provider = Components::build_finality_proof_provider(client.clone())?; let chain_info = client.info().chain; let version = config.full_version(); info!("Highest known block at #{}", chain_info.best_number); telemetry!(SUBSTRATE_INFO; "node.start"; "height" => chain_info.best_number.saturated_into::(), "best" => ?chain_info.best_hash ); let network_protocol = ::build_network_protocol(&config)?; let transaction_pool = Arc::new( Components::build_transaction_pool(config.transaction_pool.clone(), client.clone())? ); let transaction_pool_adapter = Arc::new(TransactionPoolAdapter:: { imports_external_transactions: !config.roles.is_light(), pool: transaction_pool.clone(), client: client.clone(), }); let protocol_id = { let protocol_id_full = match config.chain_spec.protocol_id() { Some(pid) => pid, None => { warn!("Using default protocol ID {:?} because none is configured in the \ chain specs", DEFAULT_PROTOCOL_ID ); DEFAULT_PROTOCOL_ID } }.as_bytes(); network::ProtocolId::from(protocol_id_full) }; let network_params = network::config::Params { roles: config.roles, network_config: config.network.clone(), chain: client.clone(), finality_proof_provider, on_demand, transaction_pool: transaction_pool_adapter.clone() as _, import_queue, protocol_id, specialization: network_protocol, }; let has_bootnodes = !network_params.network_config.boot_nodes.is_empty(); let network_mut = network::NetworkWorker::new(network_params)?; let network = network_mut.service().clone(); task_executor.spawn(network_mut .map_err(|_| ()) .select(exit.clone()) .then(|_| Ok(()))); let offchain_workers = if config.offchain_worker { Some(Arc::new(offchain::OffchainWorkers::new( client.clone(), task_executor.clone(), ))) } else { None }; { // block notifications let network = Arc::downgrade(&network); let txpool = Arc::downgrade(&transaction_pool); let wclient = Arc::downgrade(&client); let offchain = offchain_workers.as_ref().map(Arc::downgrade); let events = client.import_notification_stream() .for_each(move |notification| { let number = *notification.header.number(); if let Some(network) = network.upgrade() { network.on_block_imported(notification.hash, notification.header); } if let (Some(txpool), Some(client)) = (txpool.upgrade(), wclient.upgrade()) { Components::RuntimeServices::maintain_transaction_pool( &BlockId::hash(notification.hash), &*client, &*txpool, ).map_err(|e| warn!("Pool error processing new block: {:?}", e))?; } if let (Some(txpool), Some(offchain)) = (txpool.upgrade(), offchain.as_ref().and_then(|o| o.upgrade())) { Components::RuntimeServices::offchain_workers( &number, &offchain, &txpool, ).map_err(|e| warn!("Offchain workers error processing new block: {:?}", e))?; } Ok(()) }) .select(exit.clone()) .then(|_| Ok(())); task_executor.spawn(events); } { // finality notifications let network = Arc::downgrade(&network); // A utility stream that drops all ready items and only returns the last one. // This is used to only keep the last finality notification and avoid // overloading the sync module with notifications. struct MostRecentNotification(futures::stream::Fuse>); impl Stream for MostRecentNotification { type Item = as Stream>::Item; type Error = as Stream>::Error; fn poll(&mut self) -> Poll, Self::Error> { let mut last = None; let last = loop { match self.0.poll()? { Async::Ready(Some(item)) => { last = Some(item) } Async::Ready(None) => match last { None => return Ok(Async::Ready(None)), Some(last) => break last, }, Async::NotReady => match last { None => return Ok(Async::NotReady), Some(last) => break last, }, } }; Ok(Async::Ready(Some(last))) } } let events = MostRecentNotification(client.finality_notification_stream().fuse()) .for_each(move |notification| { if let Some(network) = network.upgrade() { network.on_block_finalized(notification.hash, notification.header); } Ok(()) }) .select(exit.clone()) .then(|_| Ok(())); task_executor.spawn(events); } { // extrinsic notifications let network = Arc::downgrade(&network); let transaction_pool_ = transaction_pool.clone(); let events = transaction_pool.import_notification_stream() .for_each(move |_| { if let Some(network) = network.upgrade() { network.trigger_repropagate(); } let status = transaction_pool_.status(); telemetry!(SUBSTRATE_INFO; "txpool.import"; "ready" => status.ready, "future" => status.future ); Ok(()) }) .select(exit.clone()) .then(|_| Ok(())); task_executor.spawn(events); } // Periodically notify the telemetry. let transaction_pool_ = transaction_pool.clone(); let client_ = client.clone(); let network_ = network.clone(); let mut sys = System::new(); let self_pid = get_current_pid(); task_executor.spawn(network.status().for_each(move |sync_status| { let info = client_.info(); let best_number = info.chain.best_number.saturated_into::(); let best_hash = info.chain.best_hash; let num_peers = sync_status.num_peers; let txpool_status = transaction_pool_.status(); let finalized_number: u64 = info.chain.finalized_number.saturated_into::(); let bandwidth_download = network_.average_download_per_sec(); let bandwidth_upload = network_.average_upload_per_sec(); #[allow(deprecated)] let backend = (*client_).backend(); let used_state_cache_size = match backend.used_state_cache_size(){ Some(size) => size, None => 0, }; // get cpu usage and memory usage of this process let (cpu_usage, memory) = if sys.refresh_process(self_pid) { let proc = sys.get_process(self_pid).expect("Above refresh_process succeeds, this should be Some(), qed"); (proc.cpu_usage(), proc.memory()) } else { (0.0, 0) }; let network_state = network_.network_state(); telemetry!( SUBSTRATE_INFO; "system.interval"; "network_state" => network_state, "peers" => num_peers, "height" => best_number, "best" => ?best_hash, "txcount" => txpool_status.ready, "cpu" => cpu_usage, "memory" => memory, "finalized_height" => finalized_number, "finalized_hash" => ?info.chain.finalized_hash, "bandwidth_download" => bandwidth_download, "bandwidth_upload" => bandwidth_upload, "used_state_cache_size" => used_state_cache_size, ); Ok(()) }).select(exit.clone()).then(|_| Ok(()))); // RPC let system_info = rpc::apis::system::SystemInfo { chain_name: config.chain_spec.name().into(), impl_name: config.impl_name.into(), impl_version: config.impl_version.into(), properties: config.chain_spec.properties(), }; let rpc = Components::RuntimeServices::start_rpc( client.clone(), network.clone(), has_bootnodes, system_info, config.rpc_http, config.rpc_ws, config.rpc_ws_max_connections, config.rpc_cors.clone(), task_executor.clone(), transaction_pool.clone(), )?; let telemetry_connection_sinks: Arc>>> = Default::default(); // Telemetry let telemetry = config.telemetry_endpoints.clone().map(|endpoints| { let is_authority = config.roles == Roles::AUTHORITY; let network_id = network.local_peer_id().to_base58(); let pubkey = format!("{}", public_key); let name = config.name.clone(); let impl_name = config.impl_name.to_owned(); let version = version.clone(); let chain_name = config.chain_spec.name().to_owned(); let telemetry_connection_sinks_ = telemetry_connection_sinks.clone(); let telemetry = tel::init_telemetry(tel::TelemetryConfig { endpoints, wasm_external_transport: None, on_connect: Box::new(move || { telemetry!(SUBSTRATE_INFO; "system.connected"; "name" => name.clone(), "implementation" => impl_name.clone(), "version" => version.clone(), "config" => "", "chain" => chain_name.clone(), "pubkey" => &pubkey, "authority" => is_authority, "network_id" => network_id.clone() ); telemetry_connection_sinks_.lock().retain(|sink| { sink.unbounded_send(()).is_ok() }); }), }); task_executor.spawn(telemetry.clone() .select(exit.clone()) .then(|_| Ok(()))); telemetry }); Ok(Service { client, network: Some(network), select_chain, transaction_pool, signal: Some(signal), keystore, config, exit, _rpc: Box::new(rpc), _telemetry: telemetry, _offchain_workers: offchain_workers, _telemetry_on_connect_sinks: telemetry_connection_sinks.clone(), }) } /// give the authority key, if we are an authority and have a key pub fn authority_key(&self) -> Option { if self.config.roles != Roles::AUTHORITY { return None } let keystore = &self.keystore; if let Ok(Some(Ok(key))) = keystore.contents().map(|keys| keys.get(0) .map(|k| keystore.load(k, &self.config.password))) { Some(key) } else { None } } /// return a shared instance of Telemetry (if enabled) pub fn telemetry(&self) -> Option { self._telemetry.as_ref().map(|t| t.clone()) } } impl Service where Components: components::Components { /// Get shared client instance. pub fn client(&self) -> Arc> { self.client.clone() } /// Get clone of select chain. pub fn select_chain(&self) -> Option<::SelectChain> { self.select_chain.clone() } /// Get shared network instance. pub fn network(&self) -> Arc> { self.network.as_ref().expect("self.network always Some").clone() } /// Get shared transaction pool instance. pub fn transaction_pool(&self) -> Arc> { self.transaction_pool.clone() } /// Get shared keystore. pub fn keystore(&self) -> &Keystore { &self.keystore } /// Get a handle to a future that will resolve on exit. pub fn on_exit(&self) -> ::exit_future::Exit { self.exit.clone() } } impl Drop for Service where Components: components::Components { fn drop(&mut self) { debug!(target: "service", "Substrate service shutdown"); drop(self.network.take()); if let Some(signal) = self.signal.take() { signal.fire(); } } } fn maybe_start_server(address: Option, start: F) -> Result, io::Error> where F: Fn(&SocketAddr) -> Result, { Ok(match address { Some(mut address) => Some(start(&address) .or_else(|e| match e.kind() { io::ErrorKind::AddrInUse | io::ErrorKind::PermissionDenied => { warn!("Unable to bind server to {}. Trying random port.", address); address.set_port(0); start(&address) }, _ => Err(e), })?), None => None, }) } /// Transaction pool adapter. pub struct TransactionPoolAdapter { imports_external_transactions: bool, pool: Arc>, client: Arc>, } impl TransactionPoolAdapter { fn best_block_id(&self) -> Option>> { Some(BlockId::hash(self.client.info().chain.best_hash)) } } /// Get transactions for propagation. /// /// Function extracted to simplify the test and prevent creating `ServiceFactory`. fn transactions_to_propagate(pool: &TransactionPool) -> Vec<(H, B::Extrinsic)> where PoolApi: ChainApi, B: BlockT, H: std::hash::Hash + Eq + runtime_primitives::traits::Member + serde::Serialize, E: txpool::error::IntoPoolError + From, { pool.ready() .filter(|t| t.is_propagateable()) .map(|t| { let hash = t.hash.clone(); let ex: B::Extrinsic = t.data.clone(); (hash, ex) }) .collect() } impl network::TransactionPool, ComponentBlock> for TransactionPoolAdapter where ::RuntimeApi: Send + Sync { fn transactions(&self) -> Vec<(ComponentExHash, ComponentExtrinsic)> { transactions_to_propagate(&self.pool) } fn import(&self, transaction: &ComponentExtrinsic) -> Option> { if !self.imports_external_transactions { debug!("Transaction rejected"); return None; } let encoded = transaction.encode(); if let Some(uxt) = Decode::decode(&mut &encoded[..]) { let best_block_id = self.best_block_id()?; match self.pool.submit_one(&best_block_id, uxt) { Ok(hash) => Some(hash), Err(e) => match e.into_pool_error() { Ok(txpool::error::Error::AlreadyImported(hash)) => { hash.downcast::>().ok() .map(|x| x.as_ref().clone()) }, Ok(e) => { debug!("Error adding transaction to the pool: {:?}", e); None }, Err(e) => { debug!("Error converting pool error: {:?}", e); None }, } } } else { debug!("Error decoding transaction"); None } } fn on_broadcasted(&self, propagations: HashMap, Vec>) { self.pool.on_broadcasted(propagations) } } /// Constructs a service factory with the given name that implements the `ServiceFactory` trait. /// The required parameters are required to be given in the exact order. Some parameters are followed /// by `{}` blocks. These blocks are required and used to initialize the given parameter. /// In these block it is required to write a closure that takes the same number of arguments, /// the corresponding function in the `ServiceFactory` trait provides. /// /// # Example /// /// ``` /// # use substrate_service::{ /// # construct_service_factory, Service, FullBackend, FullExecutor, LightBackend, LightExecutor, /// # FullComponents, LightComponents, FactoryFullConfiguration, FullClient, TaskExecutor /// # }; /// # use transaction_pool::{self, txpool::{Pool as TransactionPool}}; /// # use network::construct_simple_protocol; /// # use client::{self, LongestChain}; /// # use primitives::{Pair as PairT, ed25519}; /// # use consensus_common::import_queue::{BasicQueue, Verifier}; /// # use consensus_common::{BlockOrigin, ImportBlock, well_known_cache_keys::Id as CacheKeyId}; /// # use node_runtime::{GenesisConfig, RuntimeApi}; /// # use std::sync::Arc; /// # use node_primitives::Block; /// # use runtime_primitives::Justification; /// # use runtime_primitives::traits::Block as BlockT; /// # use grandpa; /// # construct_simple_protocol! { /// # pub struct NodeProtocol where Block = Block { } /// # } /// # struct MyVerifier; /// # impl Verifier for MyVerifier { /// # fn verify( /// # &self, /// # origin: BlockOrigin, /// # header: B::Header, /// # justification: Option, /// # body: Option>, /// # ) -> Result<(ImportBlock, Option)>>), String> { /// # unimplemented!(); /// # } /// # } /// type FullChainApi = transaction_pool::ChainApi< /// client::Client, FullExecutor, Block, RuntimeApi>, Block>; /// type LightChainApi = transaction_pool::ChainApi< /// client::Client, LightExecutor, Block, RuntimeApi>, Block>; /// /// construct_service_factory! { /// struct Factory { /// // Declare the block type /// Block = Block, /// RuntimeApi = RuntimeApi, /// // Declare the network protocol and give an initializer. /// NetworkProtocol = NodeProtocol { |config| Ok(NodeProtocol::new()) }, /// RuntimeDispatch = node_executor::Executor, /// FullTransactionPoolApi = FullChainApi /// { |config, client| Ok(TransactionPool::new(config, transaction_pool::ChainApi::new(client))) }, /// LightTransactionPoolApi = LightChainApi /// { |config, client| Ok(TransactionPool::new(config, transaction_pool::ChainApi::new(client))) }, /// Genesis = GenesisConfig, /// Configuration = (), /// FullService = FullComponents /// { |config, executor| >::new(config, executor) }, /// // Setup as Consensus Authority (if the role and key are given) /// AuthoritySetup = { /// |service: Self::FullService, executor: TaskExecutor, key: Option>| { /// Ok(service) /// }}, /// LightService = LightComponents /// { |config, executor| >::new(config, executor) }, /// FullImportQueue = BasicQueue /// { |_, client, _| Ok(BasicQueue::new(Arc::new(MyVerifier), client, None, None, None)) }, /// LightImportQueue = BasicQueue /// { |_, client| Ok(BasicQueue::new(Arc::new(MyVerifier), client, None, None, None)) }, /// SelectChain = LongestChain, Self::Block> /// { |config: &FactoryFullConfiguration, client: Arc>| { /// #[allow(deprecated)] /// Ok(LongestChain::new(client.backend().clone())) /// }}, /// FinalityProofProvider = { |client: Arc>| { /// Ok(Some(Arc::new(grandpa::FinalityProofProvider::new(client.clone(), client)) as _)) /// }}, /// } /// } /// ``` #[macro_export] macro_rules! construct_service_factory { ( $(#[$attr:meta])* struct $name:ident { Block = $block:ty, RuntimeApi = $runtime_api:ty, NetworkProtocol = $protocol:ty { $( $protocol_init:tt )* }, RuntimeDispatch = $dispatch:ty, FullTransactionPoolApi = $full_transaction:ty { $( $full_transaction_init:tt )* }, LightTransactionPoolApi = $light_transaction:ty { $( $light_transaction_init:tt )* }, Genesis = $genesis:ty, Configuration = $config:ty, FullService = $full_service:ty { $( $full_service_init:tt )* }, AuthoritySetup = { $( $authority_setup:tt )* }, LightService = $light_service:ty { $( $light_service_init:tt )* }, FullImportQueue = $full_import_queue:ty { $( $full_import_queue_init:tt )* }, LightImportQueue = $light_import_queue:ty { $( $light_import_queue_init:tt )* }, SelectChain = $select_chain:ty { $( $select_chain_init:tt )* }, FinalityProofProvider = { $( $finality_proof_provider_init:tt )* }, } ) => { $( #[$attr] )* pub struct $name {} #[allow(unused_variables)] impl $crate::ServiceFactory for $name { type Block = $block; type RuntimeApi = $runtime_api; type NetworkProtocol = $protocol; type RuntimeDispatch = $dispatch; type FullTransactionPoolApi = $full_transaction; type LightTransactionPoolApi = $light_transaction; type Genesis = $genesis; type Configuration = $config; type FullService = $full_service; type LightService = $light_service; type FullImportQueue = $full_import_queue; type LightImportQueue = $light_import_queue; type SelectChain = $select_chain; fn build_full_transaction_pool( config: $crate::TransactionPoolOptions, client: $crate::Arc<$crate::FullClient> ) -> $crate::Result<$crate::TransactionPool, $crate::Error> { ( $( $full_transaction_init )* ) (config, client) } fn build_light_transaction_pool( config: $crate::TransactionPoolOptions, client: $crate::Arc<$crate::LightClient> ) -> $crate::Result<$crate::TransactionPool, $crate::Error> { ( $( $light_transaction_init )* ) (config, client) } fn build_network_protocol(config: &$crate::FactoryFullConfiguration) -> $crate::Result { ( $( $protocol_init )* ) (config) } fn build_select_chain( config: &mut $crate::FactoryFullConfiguration, client: Arc<$crate::FullClient> ) -> $crate::Result { ( $( $select_chain_init )* ) (config, client) } fn build_full_import_queue( config: &mut $crate::FactoryFullConfiguration, client: $crate::Arc<$crate::FullClient>, select_chain: Self::SelectChain ) -> $crate::Result { ( $( $full_import_queue_init )* ) (config, client, select_chain) } fn build_light_import_queue( config: &mut FactoryFullConfiguration, client: Arc<$crate::LightClient>, ) -> Result { ( $( $light_import_queue_init )* ) (config, client) } fn build_finality_proof_provider( client: Arc<$crate::FullClient> ) -> Result>>, $crate::Error> { ( $( $finality_proof_provider_init )* ) (client) } fn new_light( config: $crate::FactoryFullConfiguration, executor: $crate::TaskExecutor ) -> $crate::Result { ( $( $light_service_init )* ) (config, executor) } fn new_full( config: $crate::FactoryFullConfiguration, executor: $crate::TaskExecutor, ) -> Result { ( $( $full_service_init )* ) (config, executor.clone()).and_then(|service| { let key = (&service).authority_key().map(Arc::new); ($( $authority_setup )*)(service, executor, key) }) } } } } #[cfg(test)] mod tests { use super::*; use consensus_common::SelectChain; use runtime_primitives::traits::BlindCheckable; use substrate_test_runtime_client::{prelude::*, runtime::{Extrinsic, Transfer}}; #[test] fn should_not_propagate_transactions_that_are_marked_as_such() { // given let (client, longest_chain) = TestClientBuilder::new().build_with_longest_chain(); let client = Arc::new(client); let pool = Arc::new(TransactionPool::new( Default::default(), transaction_pool::ChainApi::new(client.clone()) )); let best = longest_chain.best_chain().unwrap(); let transaction = Transfer { amount: 5, nonce: 0, from: AccountKeyring::Alice.into(), to: Default::default(), }.into_signed_tx(); pool.submit_one(&BlockId::hash(best.hash()), transaction.clone()).unwrap(); pool.submit_one(&BlockId::hash(best.hash()), Extrinsic::IncludeData(vec![1])).unwrap(); assert_eq!(pool.status().ready, 2); // when let transactions = transactions_to_propagate(&pool); // then assert_eq!(transactions.len(), 1); assert!(transactions[0].1.clone().check().is_ok()); // this should not panic let _ = transactions[0].1.transfer(); } }