introduce errors with info (#1834)

cli/Cargo.toml

@@ -14,19 +14,12 @@ wasm-opt = false
 crate-type = ["cdylib", "rlib"]
 
 [dependencies]
-log = "0.4.8"
-futures = { version = "0.3.4", features = ["compat"] }
-structopt = "0.3.8"
-sp-api = { git = "https://github.com/paritytech/substrate", branch = "master" }
+log = "0.4.11"
+structopt = { version = "0.3.8", optional = true }
 sp-core = { git = "https://github.com/paritytech/substrate", branch = "master" }
-sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "master" }
-sc-client-api = { git = "https://github.com/paritytech/substrate", branch = "master" }
-sc-client-db = { git = "https://github.com/paritytech/substrate", branch = "master" }
-sc-executor = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sc-tracing = { git = "https://github.com/paritytech/substrate", branch = "master" }
 service = { package = "polkadot-service", path = "../node/service", default-features = false, optional = true }
 
-tokio = { version = "0.2.13", features = ["rt-threaded"], optional = true }
 frame-benchmarking-cli = { git = "https://github.com/paritytech/substrate", branch = "master", optional = true }
 sc-cli = { git = "https://github.com/paritytech/substrate", branch = "master", optional = true }
 sc-service = { git = "https://github.com/paritytech/substrate", branch = "master", optional = true }
@@ -46,7 +39,7 @@ default = [ "wasmtime", "db", "cli", "full-node", "trie-memory-tracker" ]
 wasmtime = [ "sc-cli/wasmtime" ]
 db = [ "service/db" ]
 cli = [
-	"tokio",
+	"structopt",
 	"sc-cli",
 	"sc-service",
 	"frame-benchmarking-cli",

cli/src/lib.rs

@@ -17,7 +17,6 @@
 //! Polkadot CLI library.
 
 #![warn(missing_docs)]
-#![warn(unused_extern_crates)]
 
 #[cfg(feature = "browser")]
 mod browser;

erasure-coding/Cargo.toml

@@ -10,4 +10,4 @@ reed_solomon = { package = "reed-solomon-erasure", version = "4.0.2"}
 codec = { package = "parity-scale-codec", version = "1.3.4", default-features = false, features = ["derive"] }
 sp-core = { git = "https://github.com/paritytech/substrate", branch = "master" }
 trie = { package = "sp-trie", git = "https://github.com/paritytech/substrate", branch = "master" }
-derive_more = "0.15.0"
+thiserror = "1.0.21"

erasure-coding/src/lib.rs

@@ -30,6 +30,7 @@ use primitives::v0::{self, Hash as H256, BlakeTwo256, HashT};
 use primitives::v1;
 use sp_core::Blake2Hasher;
 use trie::{EMPTY_PREFIX, MemoryDB, Trie, TrieMut, trie_types::{TrieDBMut, TrieDB}};
+use thiserror::Error;
 
 use self::wrapped_shard::WrappedShard;
 
@@ -39,35 +40,43 @@ mod wrapped_shard;
 const MAX_VALIDATORS: usize = <galois_16::Field as reed_solomon::Field>::ORDER;
 
 /// Errors in erasure coding.
-#[derive(Debug, Clone, PartialEq, derive_more::Display)]
+#[derive(Debug, Clone, PartialEq, Error)]
 pub enum Error {
 	/// Returned when there are too many validators.
+	#[error("There are too many validators")]
 	TooManyValidators,
 	/// Cannot encode something for no validators
+	#[error("Validator set is empty")]
 	EmptyValidators,
 	/// Cannot reconstruct: wrong number of validators.
+	#[error("Validator count mismatches between encoding and decoding")]
 	WrongValidatorCount,
 	/// Not enough chunks present.
+	#[error("Not enough chunks to reconstruct message")]
 	NotEnoughChunks,
 	/// Too many chunks present.
+	#[error("Too many chunks present")]
 	TooManyChunks,
 	/// Chunks not of uniform length or the chunks are empty.
+	#[error("Chunks are not unform, mismatch in length or are zero sized")]
 	NonUniformChunks,
 	/// An uneven byte-length of a shard is not valid for GF(2^16) encoding.
+	#[error("Uneven length is not valid for field GF(2^16)")]
 	UnevenLength,
 	/// Chunk index out of bounds.
-	#[display(fmt = "Chunk is out of bounds: {} {}", _0, _1)]
-	ChunkIndexOutOfBounds(usize, usize),
+	#[error("Chunk is out of bounds: {chunk_index} not included in 0..{n_validators}")]
+	ChunkIndexOutOfBounds{ chunk_index: usize, n_validators: usize },
 	/// Bad payload in reconstructed bytes.
+	#[error("Reconstructed payload invalid")]
 	BadPayload,
 	/// Invalid branch proof.
+	#[error("Invalid branch proof")]
 	InvalidBranchProof,
 	/// Branch out of bounds.
+	#[error("Branch is out of bounds")]
 	BranchOutOfBounds,
 }
 
-impl std::error::Error for Error { }
-
 #[derive(Debug, PartialEq)]
 struct CodeParams {
 	data_shards: usize,
@@ -206,7 +215,7 @@ fn reconstruct<'a, I: 'a, T: Decode>(n_validators: usize, chunks: I) -> Result<T
 	let mut shard_len = None;
 	for (chunk_data, chunk_idx) in chunks.into_iter().take(n_validators) {
 		if chunk_idx >= n_validators {
-			return Err(Error::ChunkIndexOutOfBounds(chunk_idx, n_validators));
+			return Err(Error::ChunkIndexOutOfBounds{ chunk_index: chunk_idx, n_validators });
 		}
 
 		let shard_len = shard_len.get_or_insert_with(|| chunk_data.len());

node/collation-generation/Cargo.toml

@@ -5,7 +5,6 @@ authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2018"
 
 [dependencies]
-derive_more = "0.99.9"
 futures = "0.3.5"
 log = "0.4.8"
 polkadot-erasure-coding = { path = "../../erasure-coding" }
@@ -14,6 +13,7 @@ polkadot-node-subsystem = { path = "../subsystem" }
 polkadot-node-subsystem-util = { path = "../subsystem-util" }
 polkadot-primitives = { path = "../../primitives" }
 sp-core = { git = "https://github.com/paritytech/substrate", branch = "master" }
+thiserror = "1.0.21"
 
 [dev-dependencies]
 polkadot-node-subsystem-test-helpers = { path = "../subsystem-test-helpers" }

node/collation-generation/src/error.rs

@@ -14,19 +14,20 @@
 // You should have received a copy of the GNU General Public License
 // along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
 
+use thiserror::Error;
 
-#[derive(Debug, derive_more::From)]
+#[derive(Debug, Error)]
 pub enum Error {
-	#[from]
-	Subsystem(polkadot_node_subsystem::SubsystemError),
-	#[from]
-	OneshotRecv(futures::channel::oneshot::Canceled),
-	#[from]
-	Runtime(polkadot_node_subsystem::errors::RuntimeApiError),
-	#[from]
-	Util(polkadot_node_subsystem_util::Error),
-	#[from]
-	Erasure(polkadot_erasure_coding::Error),
+	#[error(transparent)]
+	Subsystem(#[from] polkadot_node_subsystem::SubsystemError),
+	#[error(transparent)]
+	OneshotRecv(#[from] futures::channel::oneshot::Canceled),
+	#[error(transparent)]
+	Runtime(#[from] polkadot_node_subsystem::errors::RuntimeApiError),
+	#[error(transparent)]
+	Util(#[from] polkadot_node_subsystem_util::Error),
+	#[error(transparent)]
+	Erasure(#[from] polkadot_erasure_coding::Error),
 }
 
 pub type Result<T> = std::result::Result<T, Error>;

node/core/av-store/Cargo.toml

@@ -5,12 +5,12 @@ authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2018"
 
 [dependencies]
-derive_more = "0.99.9"
 futures = "0.3.5"
 futures-timer = "3.0.2"
 kvdb = "0.7.0"
 kvdb-rocksdb = "0.9.1"
-log = "0.4.8"
+log = "0.4.11"
+thiserror = "1.0.21"
 
 codec = { package = "parity-scale-codec", version = "1.3.1", features = ["derive"] }
 erasure = { package = "polkadot-erasure-coding", path = "../../../erasure-coding" }

node/core/av-store/src/lib.rs

@@ -44,6 +44,7 @@ use polkadot_node_subsystem_util::metrics::{self, prometheus};
 use polkadot_subsystem::messages::{
 	AllMessages, AvailabilityStoreMessage, ChainApiMessage, RuntimeApiMessage, RuntimeApiRequest,
 };
+use thiserror::Error;
 
 const LOG_TARGET: &str = "availability";
 
@@ -53,22 +54,22 @@ mod columns {
 	pub const NUM_COLUMNS: u32 = 2;
 }
 
-#[derive(Debug, derive_more::From)]
+#[derive(Debug, Error)]
 enum Error {
-	#[from]
-	Chain(ChainApiError),
-	#[from]
-	Erasure(erasure::Error),
-	#[from]
-	Io(io::Error),
-	#[from]
-	Oneshot(oneshot::Canceled),
-	#[from]
-	Runtime(RuntimeApiError),
-	#[from]
-	Subsystem(SubsystemError),
-	#[from]
-	Time(SystemTimeError),
+	#[error(transparent)]
+	RuntimeAPI(#[from] RuntimeApiError),
+	#[error(transparent)]
+	ChainAPI(#[from] ChainApiError),
+	#[error(transparent)]
+	Erasure(#[from] erasure::Error),
+	#[error(transparent)]
+	Io(#[from] io::Error),
+	#[error(transparent)]
+	Oneshot(#[from] oneshot::Canceled),
+	#[error(transparent)]
+	Subsystem(#[from] SubsystemError),
+	#[error(transparent)]
+	Time(#[from] SystemTimeError),
 }
 
 /// A wrapper type for delays.

node/core/backing/Cargo.toml

@@ -6,19 +6,16 @@ edition = "2018"
 
 [dependencies]
 futures = "0.3.5"
-sp-api = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-keystore = { git = "https://github.com/paritytech/substrate", branch = "master" }
-sc-client-api = { git = "https://github.com/paritytech/substrate", branch = "master" }
-sp-blockchain = { git = "https://github.com/paritytech/substrate", branch = "master" }
 polkadot-primitives = { path = "../../../primitives" }
 polkadot-node-primitives = { path = "../../primitives" }
 polkadot-subsystem = { package = "polkadot-node-subsystem", path = "../../subsystem" }
 polkadot-node-subsystem-util = { path = "../../subsystem-util" }
 erasure-coding = { package = "polkadot-erasure-coding", path = "../../../erasure-coding" }
 statement-table = { package = "polkadot-statement-table", path = "../../../statement-table" }
-derive_more = "0.99.9"
 bitvec = { version = "0.17.4", default-features = false, features = ["alloc"] }
-log = "0.4.8"
+log = "0.4.11"
+thiserror = "1.0.21"
 
 [dev-dependencies]
 sp-core = { git = "https://github.com/paritytech/substrate", branch = "master" }

node/core/backing/src/lib.rs

@@ -16,6 +16,8 @@
 
 //! Implements a `CandidateBackingSubsystem`.
 
+#![deny(unused_crate_dependencies)]
+
 use std::collections::{HashMap, HashSet};
 use std::convert::TryFrom;
 use std::pin::Pin;
@@ -64,22 +66,26 @@ use statement_table::{
 		SignedStatement as TableSignedStatement, Summary as TableSummary,
 	},
 };
+use thiserror::Error;
 
-#[derive(Debug, derive_more::From)]
+#[derive(Debug, Error)]
 enum Error {
+	#[error("Candidate is not found")]
 	CandidateNotFound,
+	#[error("Signature is invalid")]
 	InvalidSignature,
-	StoreFailed,
-	#[from]
-	Erasure(erasure_coding::Error),
-	#[from]
-	ValidationFailed(ValidationFailed),
-	#[from]
-	Oneshot(oneshot::Canceled),
-	#[from]
-	Mpsc(mpsc::SendError),
-	#[from]
-	UtilError(util::Error),
+	#[error("Failed to send candidates {0:?}")]
+	Send(Vec<NewBackedCandidate>),
+	#[error("Oneshot never resolved")]
+	Oneshot(#[from] #[source] oneshot::Canceled),
+	#[error("Obtaining erasure chunks failed")]
+	ObtainErasureChunks(#[from] #[source] erasure_coding::Error),
+	#[error(transparent)]
+	ValidationFailed(#[from] ValidationFailed),
+	#[error(transparent)]
+	Mpsc(#[from] mpsc::SendError),
+	#[error(transparent)]
+	UtilError(#[from] util::Error),
 }
 
 /// Holds all data needed for candidate backing job operation.
@@ -468,7 +474,7 @@ impl CandidateBackingJob {
 			CandidateBackingMessage::GetBackedCandidates(_, tx) => {
 				let backed = self.get_backed();
 
-				tx.send(backed).map_err(|_| oneshot::Canceled)?;
+				tx.send(backed).map_err(|data| Error::Send(data))?;
 			}
 		}
 
@@ -640,7 +646,7 @@ impl CandidateBackingJob {
 			)
 		).await?;
 
-		rx.await?.map_err(|_| Error::StoreFailed)?;
+		let _ = rx.await?;
 
 		Ok(())
 	}

node/core/bitfield-signing/Cargo.toml

@@ -6,11 +6,11 @@ edition = "2018"
 
 [dependencies]
 bitvec = "0.17.4"
-derive_more = "0.99.9"
 futures = "0.3.5"
-log = "0.4.8"
+log = "0.4.11"
 polkadot-primitives = { path = "../../../primitives" }
 polkadot-node-subsystem = { path = "../../subsystem" }
 polkadot-node-subsystem-util = { path = "../../subsystem-util" }
 sp-keystore = { git = "https://github.com/paritytech/substrate", branch = "master" }
 wasm-timer = "0.2.4"
+thiserror = "1.0.21"

node/core/bitfield-signing/src/lib.rs

@@ -16,6 +16,9 @@
 
 //! The bitfield signing subsystem produces `SignedAvailabilityBitfield`s once per block.
 
+#![deny(unused_crate_dependencies, unused_results)]
+#![warn(missing_docs)]
+
 use bitvec::bitvec;
 use futures::{
 	channel::{mpsc, oneshot},
@@ -37,6 +40,7 @@ use polkadot_node_subsystem_util::{
 use polkadot_primitives::v1::{AvailabilityBitfield, CoreState, Hash, ValidatorIndex};
 use std::{convert::TryFrom, pin::Pin, time::Duration};
 use wasm_timer::{Delay, Instant};
+use thiserror::Error;
 
 /// Delay between starting a bitfield signing job and its attempting to create a bitfield.
 const JOB_DELAY: Duration = Duration::from_millis(1500);
@@ -45,6 +49,7 @@ const JOB_DELAY: Duration = Duration::from_millis(1500);
 pub struct BitfieldSigningJob;
 
 /// Messages which a `BitfieldSigningJob` is prepared to receive.
+#[allow(missing_docs)]
 pub enum ToJob {
 	BitfieldSigning(BitfieldSigningMessage),
 	Stop,
@@ -79,6 +84,7 @@ impl From<BitfieldSigningMessage> for ToJob {
 }
 
 /// Messages which may be sent from a `BitfieldSigningJob`.
+#[allow(missing_docs)]
 pub enum FromJob {
 	AvailabilityStore(AvailabilityStoreMessage),
 	BitfieldDistribution(BitfieldDistributionMessage),
@@ -112,28 +118,28 @@ impl TryFrom<AllMessages> for FromJob {
 }
 
 /// Errors we may encounter in the course of executing the `BitfieldSigningSubsystem`.
-#[derive(Debug, derive_more::From)]
+#[derive(Debug, Error)]
 pub enum Error {
 	/// error propagated from the utility subsystem
-	#[from]
-	Util(util::Error),
+	#[error(transparent)]
+	Util(#[from] util::Error),
 	/// io error
-	#[from]
-	Io(std::io::Error),
+	#[error(transparent)]
+	Io(#[from] std::io::Error),
 	/// a one shot channel was canceled
-	#[from]
-	Oneshot(oneshot::Canceled),
+	#[error(transparent)]
+	Oneshot(#[from] oneshot::Canceled),
 	/// a mspc channel failed to send
-	#[from]
-	MpscSend(mpsc::SendError),
+	#[error(transparent)]
+	MpscSend(#[from] mpsc::SendError),
 	/// several errors collected into one
-	#[from]
+	#[error("Multiple errours occured: {0:?}")]
 	Multiple(Vec<Error>),
 	/// the runtime API failed to return what we wanted
-	#[from]
-	Runtime(RuntimeApiError),
+	#[error(transparent)]
+	Runtime(#[from] RuntimeApiError),
 	/// the keystore failed to process signing request
-	#[from]
+	#[error("Keystore failed: {0:?}")]
 	Keystore(KeystoreError),
 }
 
@@ -252,7 +258,7 @@ async fn construct_availability_bitfield(
 	if errs.is_empty() {
 		Ok(out.into_inner().into())
 	} else {
-		Err(errs.into())
+		Err(Error::Multiple(errs.into()))
 	}
 }
 

node/core/candidate-selection/Cargo.toml

@@ -5,9 +5,9 @@ authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2018"
 
 [dependencies]
-derive_more = "0.99.9"
 futures = "0.3.5"
-log = "0.4.8"
+log = "0.4.11"
+thiserror = "1.0.21"
 polkadot-primitives = { path = "../../../primitives" }
 polkadot-node-primitives = { path = "../../primitives" }
 polkadot-node-subsystem = { path = "../../subsystem" }

node/core/candidate-selection/src/lib.rs

@@ -17,7 +17,7 @@
 //! The provisioner is responsible for assembling a relay chain block
 //! from a set of available parachain candidates of its choice.
 
-#![deny(missing_docs)]
+#![deny(missing_docs, unused_crate_dependencies, unused_results)]
 
 use futures::{
 	channel::{mpsc, oneshot},
@@ -39,6 +39,7 @@ use polkadot_primitives::v1::{
 	CandidateDescriptor, CandidateReceipt, CollatorId, Hash, Id as ParaId, PoV,
 };
 use std::{convert::TryFrom, pin::Pin, sync::Arc};
+use thiserror::Error;
 
 const TARGET: &'static str = "candidate_selection";
 
@@ -116,18 +117,18 @@ impl TryFrom<AllMessages> for FromJob {
 	}
 }
 
-#[derive(Debug, derive_more::From)]
+#[derive(Debug, Error)]
 enum Error {
-	#[from]
-	Sending(mpsc::SendError),
-	#[from]
-	Util(util::Error),
-	#[from]
-	OneshotRecv(oneshot::Canceled),
-	#[from]
-	ChainApi(ChainApiError),
-	#[from]
-	Runtime(RuntimeApiError),
+	#[error(transparent)]
+	Sending(#[from] mpsc::SendError),
+	#[error(transparent)]
+	Util(#[from] util::Error),
+	#[error(transparent)]
+	OneshotRecv(#[from] oneshot::Canceled),
+	#[error(transparent)]
+	ChainApi(#[from] ChainApiError),
+	#[error(transparent)]
+	Runtime(#[from] RuntimeApiError),
 }
 
 impl JobTrait for CandidateSelectionJob {
@@ -149,14 +150,13 @@ impl JobTrait for CandidateSelectionJob {
 		receiver: mpsc::Receiver<ToJob>,
 		sender: mpsc::Sender<FromJob>,
 	) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send>> {
-		async move {
+		Box::pin(async move {
 			let job = CandidateSelectionJob::new(metrics, sender, receiver);
 
 			// it isn't necessary to break run_loop into its own function,
 			// but it's convenient to separate the concerns in this way
 			job.run_loop().await
-		}
-		.boxed()
+		})
 	}
 }
 

node/core/candidate-validation/Cargo.toml

@@ -5,11 +5,9 @@ authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2018"
 
 [dependencies]
-derive_more = "0.99.9"
 futures = "0.3.5"
-log = "0.4.8"
+log = "0.4.11"
 
-sp-blockchain = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-core = { package = "sp-core", git = "https://github.com/paritytech/substrate", branch = "master" }
 parity-scale-codec = { version = "1.3.0", default-features = false, features = ["bit-vec", "derive"] }
 

node/core/candidate-validation/src/lib.rs

@@ -20,8 +20,11 @@
 //! according to a validation function. This delegates validation to an underlying
 //! pool of processes used for execution of the Wasm.
 
+#![deny(unused_crate_dependencies, unused_results)]
+#![warn(missing_docs)]
+
 use polkadot_subsystem::{
-	Subsystem, SubsystemContext, SpawnedSubsystem, SubsystemResult,
+	Subsystem, SubsystemContext, SpawnedSubsystem, SubsystemResult, SubsystemError,
 	FromOverseer, OverseerSignal,
 	messages::{
 		AllMessages, CandidateValidationMessage, RuntimeApiMessage,
@@ -116,9 +119,13 @@ impl<S, C> Subsystem<C> for CandidateValidationSubsystem<S> where
 	S: SpawnNamed + Clone + 'static,
 {
 	fn start(self, ctx: C) -> SpawnedSubsystem {
+		let future = run(ctx, self.spawn, self.metrics)
+			.map_err(|e| SubsystemError::with_origin("candidate-validation", e))
+			.map(|_| ())
+			.boxed();
 		SpawnedSubsystem {
 			name: "candidate-validation-subsystem",
-			future: run(ctx, self.spawn, self.metrics).map(|_| ()).boxed(),
+			future,
 		}
 	}
 }

node/core/chain-api/src/lib.rs

@@ -27,9 +27,12 @@
 //! * Last finalized block number
 //! * Ancestors
 
+#![deny(unused_crate_dependencies, unused_results)]
+#![warn(missing_docs)]
+
 use polkadot_subsystem::{
 	FromOverseer, OverseerSignal,
-	SpawnedSubsystem, Subsystem, SubsystemResult, SubsystemContext,
+	SpawnedSubsystem, Subsystem, SubsystemResult, SubsystemError, SubsystemContext,
 	messages::ChainApiMessage,
 };
 use polkadot_node_subsystem_util::{
@@ -61,8 +64,12 @@ impl<Client, Context> Subsystem<Context> for ChainApiSubsystem<Client> where
 	Context: SubsystemContext<Message = ChainApiMessage>
 {
 	fn start(self, ctx: Context) -> SpawnedSubsystem {
+		let future = run(ctx, self)
+			.map_err(|e| SubsystemError::with_origin("chain-api", e))
+			.map(|_| ())
+			.boxed();
 		SpawnedSubsystem {
-			future: run(ctx, self).map(|_| ()).boxed(),
+			future,
 			name: "chain-api-subsystem",
 		}
 	}
@@ -112,7 +119,10 @@ where
 						let maybe_header = subsystem.client.header(BlockId::Hash(hash));
 						match maybe_header {
 							// propagate the error
-							Err(e) => Some(Err(e.to_string().into())),
+							Err(e) => {
+								let e = e.to_string().into();
+								Some(Err(e))
+							},
 							// fewer than `k` ancestors are available
 							Ok(None) => None,
 							Ok(Some(header)) => {

node/core/proposer/Cargo.toml

@@ -6,16 +6,13 @@ edition = "2018"
 
 [dependencies]
 futures = "0.3.4"
-futures-timer = "3.0.1"
 log = "0.4.8"
-parity-scale-codec = "1.3.4"
 polkadot-node-subsystem = { path = "../../subsystem" }
 polkadot-overseer = { path = "../../overseer" }
 polkadot-primitives = { path = "../../../primitives" }
 sc-basic-authorship = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sc-block-builder = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sc-client-api = { git = "https://github.com/paritytech/substrate", branch = "master" }
-sc-telemetry = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-api = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-blockchain = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-consensus = { git = "https://github.com/paritytech/substrate", branch = "master" }
@@ -23,5 +20,4 @@ sp-core = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-inherents = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-transaction-pool = { git = "https://github.com/paritytech/substrate", branch = "master" }
-tokio-executor = { version = "0.2.0-alpha.6", features = ["blocking"] }
 wasm-timer = "0.2.4"

node/core/proposer/src/lib.rs

+// Copyright 2020 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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.
+