Recover transaction pool on light client (#3833)

* recover tx pool on light client

* revert local tests fix

* removed import renamings

* futures03::Future -> std::future::Future

* Update core/transaction-pool/graph/src/error.rs

Co-Authored-By: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* replace remove_from_ready with remove_invalid

* avoid excess hashing

* debug -> warn

* TransactionPool + BasicTransactionPool

* pause future tx reject when resubmitting

* bump impl_version to make CI happy

* and revert back local test fixes

* alter doc to restart CI

* Transaction::clone() -> Transaction::duplicate()

* transactions -> updated_tranasctions

* remove explicit consensus-common ref

* ::std:: -> std::

* manual set/unset flag -> calling clusore with given flag value

* removed comments

* removed force argument

* BestIterator -> Box<Iterator>

* separate crate for TxPool + Maintainer trait

* long line fix

* pos-merge fix

* fix benches compilation

* Rename txpoolapi to txpool_api

* Clean up.

* Finalize merge.

* post-merge fix

* Move transaction pool api to primitives directly.

* Consistent naming for txpool-runtime-api

* Warn about missing docs.

* Move  abstraction for offchain calls to tx-pool-api.

* Merge RPC instantiation.

* Update cargo.lock

* Post merge fixes.

* Avoid depending on client.

* Fix build

substrate/primitives/transaction-pool/src/error.rs

@@ -0,0 +1,82 @@
+// Copyright 2018-2019 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 <http://www.gnu.org/licenses/>.
+
+//! Transaction pool errors.
+
+use sr_primitives::transaction_validity::{
+	TransactionPriority as Priority, InvalidTransaction, UnknownTransaction,
+};
+
+/// Transaction pool result.
+pub type Result<T> = std::result::Result<T, Error>;
+
+/// Transaction pool error type.
+#[derive(Debug, derive_more::Display, derive_more::From)]
+pub enum Error {
+	/// Transaction is not verifiable yet, but might be in the future.
+	#[display(fmt="Unknown transaction validity: {:?}", _0)]
+	UnknownTransaction(UnknownTransaction),
+	/// Transaction is invalid.
+	#[display(fmt="Invalid transaction validity: {:?}", _0)]
+	InvalidTransaction(InvalidTransaction),
+	/// The transaction validity returned no "provides" tag.
+	///
+	/// Such transactions are not accepted to the pool, since we use those tags
+	/// to define identity of transactions (occupance of the same "slot").
+	#[display(fmt="The transaction does not provide any tags, so the pool can't identify it.")]
+	NoTagsProvided,
+	/// The transaction is temporarily banned.
+	#[display(fmt="Temporarily Banned")]
+	TemporarilyBanned,
+	/// The transaction is already in the pool.
+	#[display(fmt="[{:?}] Already imported", _0)]
+	AlreadyImported(Box<dyn std::any::Any + Send>),
+	/// The transaction cannot be imported cause it's a replacement and has too low priority.
+	#[display(fmt="Too low priority ({} > {})", old, new)]
+	TooLowPriority {
+		/// Transaction already in the pool.
+		old: Priority,
+		/// Transaction entering the pool.
+		new: Priority
+	},
+	/// Deps cycle etected and we couldn't import transaction.
+	#[display(fmt="Cycle Detected")]
+	CycleDetected,
+	/// Transaction was dropped immediately after it got inserted.
+	#[display(fmt="Transaction couldn't enter the pool because of the limit.")]
+	ImmediatelyDropped,
+	/// Invalid block id.
+	InvalidBlockId(String),
+	/// The pool is not accepting future transactions.
+	#[display(fmt="The pool is not accepting future transactions")]
+	RejectedFutureTransaction,
+}
+
+impl std::error::Error for Error {}
+
+/// Transaction pool error conversion.
+pub trait IntoPoolError: ::std::error::Error + Send + Sized {
+	/// Try to extract original `Error`
+	///
+	/// This implementation is optional and used only to
+	/// provide more descriptive error messages for end users
+	/// of RPC API.
+	fn into_pool_error(self) -> ::std::result::Result<Error, Self> { Err(self) }
+}
+
+impl IntoPoolError for Error {
+	fn into_pool_error(self) -> ::std::result::Result<Error, Self> { Ok(self) }
+}