Implement hardcoded sync in the light client (#8075)

* Implement hardcoded sync

* Fix concerns

* Remove artifact

* Fix cli tests

* Fix compilation

* Update hardcoded sync block

* Don't use any data fetch for the light service

json/src/spec/hardcoded_sync.rs

@@ -0,0 +1,63 @@
+// Copyright 2018 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity 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.
+
+// Parity 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 Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Spec hardcoded synchronization deserialization for the light client.
+
+use hash::H256;
+use uint::Uint;
+
+/// Spec hardcoded sync.
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+pub struct HardcodedSync {
+	/// Hexadecimal of the RLP encoding of the header of the block to start synchronization from.
+	pub header: String,
+	/// Total difficulty including the block of `header`.
+	#[serde(rename="totalDifficulty")]
+	pub total_difficulty: Uint,
+	/// Ordered trie roots of blocks before and including `header`.
+	#[serde(rename="CHTs")]
+	pub chts: Vec<H256>,
+}
+
+#[cfg(test)]
+mod tests {
+	use serde_json;
+	use uint::Uint;
+	use ethereum_types::{U256, H256 as Eth256};
+	use hash::H256;
+	use spec::hardcoded_sync::HardcodedSync;
+
+	#[test]
+	fn hardcoded_sync_deserialization() {
+		let s = r#"{
+			"header": "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",
+			"totalDifficulty": "0x400000000",
+			"CHTs": [
+				"0x11bbe8db4e347b4e8c937c1c8370e4b5ed33adb3db69cbdb7a38e1e50b1b82fa",
+				"0xd7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544"
+			]
+		}"#;
+		let deserialized: HardcodedSync = serde_json::from_str(s).unwrap();
+		assert_eq!(deserialized, HardcodedSync {
+			header: String::from("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"),
+			total_difficulty: Uint(U256::from(0x400000000u64)),
+			chts: vec![
+				H256(Eth256::from("0x11bbe8db4e347b4e8c937c1c8370e4b5ed33adb3db69cbdb7a38e1e50b1b82fa")),
+				H256(Eth256::from("0xd7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544")),
+			]
+		});
+	}
+}

json/src/spec/mod.rs

@@ -30,6 +30,7 @@ pub mod basic_authority;
 pub mod authority_round;
 pub mod tendermint;
 pub mod null_engine;
+pub mod hardcoded_sync;
 
 pub use self::account::Account;
 pub use self::builtin::{Builtin, Pricing, Linear};
@@ -45,3 +46,4 @@ pub use self::basic_authority::{BasicAuthority, BasicAuthorityParams};
 pub use self::authority_round::{AuthorityRound, AuthorityRoundParams};
 pub use self::tendermint::{Tendermint, TendermintParams};
 pub use self::null_engine::{NullEngine, NullEngineParams};
+pub use self::hardcoded_sync::HardcodedSync;

json/src/spec/spec.rs

@@ -19,7 +19,7 @@
 use std::io::Read;
 use serde_json;
 use serde_json::Error;
-use spec::{Params, Genesis, Engine, State};
+use spec::{Params, Genesis, Engine, State, HardcodedSync};
 
 /// Spec deserialization.
 #[derive(Debug, PartialEq, Deserialize)]
@@ -39,6 +39,9 @@ pub struct Spec {
 	pub accounts: State,
 	/// Boot nodes.
 	pub nodes: Option<Vec<String>>,
+	/// Hardcoded synchronization for the light client.
+	#[serde(rename="hardcodedSync")]
+	pub hardcoded_sync: Option<HardcodedSync>,
 }
 
 impl Spec {
@@ -104,6 +107,14 @@ mod tests {
 		"0000000000000000000000000000000000000003": { "balance": "1", "nonce": "1048576", "builtin": { "name": "ripemd160", "pricing": { "linear": { "base": 600, "word": 120 } } } },
 		"0000000000000000000000000000000000000004": { "balance": "1", "nonce": "1048576", "builtin": { "name": "identity", "pricing": { "linear": { "base": 15, "word": 3 } } } },
 		"102e61f5d8f9bc71d0ad4a084df4e65e05ce0e1c": { "balance": "1606938044258990275541962092341162602522202993782792835301376", "nonce": "1048576" }
+	},
+	"hardcodedSync": {
+		"header": "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",
+		"totalDifficulty": "0x400000000",
+		"CHTs": [
+			"0x11bbe8db4e347b4e8c937c1c8370e4b5ed33adb3db69cbdb7a38e1e50b1b82fa",
+			"0xd7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544"
+		]
 	}
 		}"#;
 		let _deserialized: Spec = serde_json::from_str(s).unwrap();

json/src/uint.rs

@@ -18,7 +18,7 @@
 
 use std::fmt;
 use std::str::FromStr;
-use serde::{Deserialize, Deserializer};
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use serde::de::{Error, Visitor, Unexpected};
 use ethereum_types::U256;
 
@@ -50,6 +50,13 @@ impl Into<u8> for Uint {
 	}
 }
 
+impl Serialize for Uint {
+	fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+		where S: Serializer {
+		self.0.to_string().serialize(serializer)
+	}
+}
+
 impl<'a> Deserialize<'a> for Uint {
 	fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
 		where D: Deserializer<'a> {