[RPC-Spec-V2] chainHead: use integer for block index and adjust Runti…

…meVersion JSON format (paritytech#1666)

This PR adjusts the serialized format of the the returned RuntimeVersion
in the rpc-spec-v2 methods. This is done to match the format defined
here:
https://paritytech.github.io/json-rpc-interface-spec/api/chainHead_unstable_follow.html#about-the-runtime

- ##### `apis` field as object
`apis` field of `RuntimeVersion` is now returned as an object, e.g. 
```
"apis": {
      "0xdf6acb689907609b": 3,
      "0x37e397fc7c91f5e4": 1,
}
```
instead of 
```
"apis": [
      ["0xdf6acb689907609b", 3],
      ["0x37e397fc7c91f5e4", 1],
]
```
- ##### removed `stateVersion` and `authoringVersion`
`stateVersion` and `authoringVersion` are no longer returned in the
`RuntimeVersion` JSON Object.

- ##### block index in chain head events as integer

### Related Issues

Closes: paritytech#1507
Closes: paritytech#1146

### Testing Done
Adjusted existing tests to make sure data is returned in the correct
format.

substrate/client/rpc-spec-v2/Cargo.toml

@@ -36,7 +36,6 @@ tokio = { version = "1.22.0", features = ["sync"] }
 array-bytes = "6.1"
 log = "0.4.17"
 futures-util = { version = "0.3.19", default-features = false }
-
 [dev-dependencies]
 serde_json = "1.0"
 tokio = { version = "1.22.0", features = ["macros"] }

substrate/client/rpc-spec-v2/src/chain_head/chain_head_follow.rs

@@ -158,7 +158,7 @@ where
 		let parent = match parent {
 			Some(parent) => parent,
 			// Nothing to compare against, always report.
-			None => return Some(RuntimeEvent::Valid(RuntimeVersionEvent { spec: block_rt })),
+			None => return Some(RuntimeEvent::Valid(RuntimeVersionEvent { spec: block_rt.into() })),
 		};
 
 		let parent_rt = match self.client.runtime_version_at(parent) {
@@ -168,7 +168,7 @@ where
 
 		// Report the runtime version change.
 		if block_rt != parent_rt {
-			Some(RuntimeEvent::Valid(RuntimeVersionEvent { spec: block_rt }))
+			Some(RuntimeEvent::Valid(RuntimeVersionEvent { spec: block_rt.into() }))
 		} else {
 			None
 		}

substrate/client/rpc-spec-v2/src/chain_head/error.rs

@@ -69,7 +69,6 @@ impl From<Error> for ErrorObject<'static> {
 			Error::InvalidSubscriptionID => ErrorObject::owned(INVALID_SUB_ID, msg, None::<()>),
 			Error::InvalidContinue => ErrorObject::owned(INVALID_CONTINUE, msg, None::<()>),
 		}
-		.into()
 	}
 }
 

substrate/client/rpc-spec-v2/src/chain_head/event.rs

@@ -21,6 +21,7 @@
 use serde::{ser::SerializeStruct, Deserialize, Serialize, Serializer};
 use sp_api::ApiError;
 use sp_version::RuntimeVersion;
+use std::collections::BTreeMap;
 
 /// The operation could not be processed due to an error.
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
@@ -35,11 +36,47 @@ pub struct ErrorEvent {
 /// This event is generated for:
 ///   - the first announced block by the follow subscription
 ///   - blocks that suffered a change in runtime compared with their parents
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 #[serde(rename_all = "camelCase")]
 pub struct RuntimeVersionEvent {
 	/// The runtime version.
-	pub spec: RuntimeVersion,
+	pub spec: ChainHeadRuntimeVersion,
+}
+
+/// Simplified type clone of `sp_version::RuntimeVersion`. Used instead of
+/// `sp_version::RuntimeVersion` to conform to RPC spec V2.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ChainHeadRuntimeVersion {
+	/// Identifies the different Substrate runtimes.
+	pub spec_name: String,
+	/// Name of the implementation of the spec.
+	pub impl_name: String,
+	/// Version of the runtime specification.
+	pub spec_version: u32,
+	/// Version of the implementation of the specification.
+	pub impl_version: u32,
+	/// Map of all supported API "features" and their versions.
+	pub apis: BTreeMap<String, u32>,
+	/// Transaction version.
+	pub transaction_version: u32,
+}
+
+impl From<RuntimeVersion> for ChainHeadRuntimeVersion {
+	fn from(val: RuntimeVersion) -> Self {
+		Self {
+			spec_name: val.spec_name.into(),
+			impl_name: val.impl_name.into(),
+			spec_version: val.spec_version,
+			impl_version: val.impl_version,
+			apis: val
+				.apis
+				.into_iter()
+				.map(|(api, version)| (sp_core::bytes::to_hex(api, false), *version))
+				.collect(),
+			transaction_version: val.transaction_version,
+		}
+	}
 }
 
 /// The runtime event generated if the `follow` subscription
@@ -380,7 +417,7 @@ mod tests {
 			..Default::default()
 		};
 
-		let runtime_event = RuntimeEvent::Valid(RuntimeVersionEvent { spec: runtime });
+		let runtime_event = RuntimeEvent::Valid(RuntimeVersionEvent { spec: runtime.into() });
 		let mut initialized = Initialized {
 			finalized_block_hash: "0x1".into(),
 			finalized_block_runtime: Some(runtime_event),
@@ -391,8 +428,8 @@ mod tests {
 		let ser = serde_json::to_string(&event).unwrap();
 		let exp = concat!(
 			r#"{"event":"initialized","finalizedBlockHash":"0x1","#,
-			r#""finalizedBlockRuntime":{"type":"valid","spec":{"specName":"ABC","implName":"Impl","authoringVersion":0,"#,
-			r#""specVersion":1,"implVersion":0,"apis":[],"transactionVersion":0,"stateVersion":0}}}"#,
+			r#""finalizedBlockRuntime":{"type":"valid","spec":{"specName":"ABC","implName":"Impl","#,
+			r#""specVersion":1,"implVersion":0,"apis":{},"transactionVersion":0}}}"#,
 		);
 		assert_eq!(ser, exp);
 
@@ -429,10 +466,11 @@ mod tests {
 			spec_name: "ABC".into(),
 			impl_name: "Impl".into(),
 			spec_version: 1,
+			apis: vec![([0, 0, 0, 0, 0, 0, 0, 0], 2), ([1, 0, 0, 0, 0, 0, 0, 0], 3)].into(),
 			..Default::default()
 		};
 
-		let runtime_event = RuntimeEvent::Valid(RuntimeVersionEvent { spec: runtime });
+		let runtime_event = RuntimeEvent::Valid(RuntimeVersionEvent { spec: runtime.into() });
 		let mut new_block = NewBlock {
 			block_hash: "0x1".into(),
 			parent_block_hash: "0x2".into(),
@@ -445,8 +483,8 @@ mod tests {
 		let ser = serde_json::to_string(&event).unwrap();
 		let exp = concat!(
 			r#"{"event":"newBlock","blockHash":"0x1","parentBlockHash":"0x2","#,
-			r#""newRuntime":{"type":"valid","spec":{"specName":"ABC","implName":"Impl","authoringVersion":0,"#,
-			r#""specVersion":1,"implVersion":0,"apis":[],"transactionVersion":0,"stateVersion":0}}}"#,
+			r#""newRuntime":{"type":"valid","spec":{"specName":"ABC","implName":"Impl","#,
+			r#""specVersion":1,"implVersion":0,"apis":{"0x0000000000000000":2,"0x0100000000000000":3},"transactionVersion":0}}}"#,
 		);
 		assert_eq!(ser, exp);
 

substrate/client/rpc-spec-v2/src/chain_head/tests.rs

@@ -234,17 +234,17 @@ async fn follow_with_runtime() {
 	let event: FollowEvent<String> = get_next_event(&mut sub).await;
 
 	// it is basically json-encoded substrate_test_runtime_client::runtime::VERSION
-	let runtime_str = "{\"specName\":\"test\",\"implName\":\"parity-test\",\"authoringVersion\":1,\
+	let runtime_str = "{\"specName\":\"test\",\"implName\":\"parity-test\",\"authoringVersion\":0,\
 		\"specVersion\":2,\"implVersion\":2,\"apis\":[[\"0xdf6acb689907609b\",4],\
 		[\"0x37e397fc7c91f5e4\",2],[\"0xd2bc9897eed08f15\",3],[\"0x40fe3ad401f8959a\",6],\
 		[\"0xbc9d89904f5b923f\",1],[\"0xc6e9a76309f39b09\",2],[\"0xdd718d5cc53262d4\",1],\
 		[\"0xcbca25e39f142387\",2],[\"0xf78b278be53f454c\",2],[\"0xab3c0572291feb8b\",1],\
-		[\"0xed99c5acb25eedf5\",3],[\"0xfbc577b9d747efd6\",1]],\"transactionVersion\":1,\"stateVersion\":1}";
+		[\"0xed99c5acb25eedf5\",3],[\"0xfbc577b9d747efd6\",1]],\"transactionVersion\":1,\"stateVersion\":0}";
 
 	let runtime: RuntimeVersion = serde_json::from_str(runtime_str).unwrap();
 
 	let finalized_block_runtime =
-		Some(RuntimeEvent::Valid(RuntimeVersionEvent { spec: runtime.clone() }));
+		Some(RuntimeEvent::Valid(RuntimeVersionEvent { spec: runtime.clone().into() }));
 	// Runtime must always be reported with the first event.
 	let expected = FollowEvent::Initialized(Initialized {
 		finalized_block_hash: format!("{:?}", finalized_hash),
@@ -308,7 +308,8 @@ async fn follow_with_runtime() {
 	let best_hash = block.header.hash();
 	client.import(BlockOrigin::Own, block.clone()).await.unwrap();
 
-	let new_runtime = Some(RuntimeEvent::Valid(RuntimeVersionEvent { spec: runtime.clone() }));
+	let new_runtime =
+		Some(RuntimeEvent::Valid(RuntimeVersionEvent { spec: runtime.clone().into() }));
 	let event: FollowEvent<String> = get_next_event(&mut sub).await;
 	let expected = FollowEvent::NewBlock(NewBlock {
 		block_hash: format!("{:?}", best_hash),

substrate/client/rpc-spec-v2/src/transaction/event.rs

@@ -34,7 +34,6 @@ use serde::{Deserialize, Serialize};
 #[serde(rename_all = "camelCase")]
 pub struct TransactionBroadcasted {
 	/// The number of peers the transaction was broadcasted to.
-	#[serde(with = "as_string")]
 	pub num_peers: usize,
 }
 
@@ -45,7 +44,6 @@ pub struct TransactionBlock<Hash> {
 	/// The hash of the block the transaction was included into.
 	pub hash: Hash,
 	/// The index (zero-based) of the transaction within the body of the block.
-	#[serde(with = "as_string")]
 	pub index: usize,
 }
 
@@ -224,22 +222,6 @@ impl<Hash> From<TransactionEventIR<Hash>> for TransactionEvent<Hash> {
 	}
 }
 
-/// Serialize and deserialize helper as string.
-mod as_string {
-	use super::*;
-	use serde::{Deserializer, Serializer};
-
-	pub fn serialize<S: Serializer>(data: &usize, serializer: S) -> Result<S::Ok, S::Error> {
-		data.to_string().serialize(serializer)
-	}
-
-	pub fn deserialize<'de, D: Deserializer<'de>>(deserializer: D) -> Result<usize, D::Error> {
-		String::deserialize(deserializer)?
-			.parse()
-			.map_err(|e| serde::de::Error::custom(format!("Parsing failed: {}", e)))
-	}
-}
-
 #[cfg(test)]
 mod tests {
 	use super::*;
@@ -263,7 +245,7 @@ mod tests {
 			TransactionEvent::Broadcasted(TransactionBroadcasted { num_peers: 2 });
 		let ser = serde_json::to_string(&event).unwrap();
 
-		let exp = r#"{"event":"broadcasted","numPeers":"2"}"#;
+		let exp = r#"{"event":"broadcasted","numPeers":2}"#;
 		assert_eq!(ser, exp);
 
 		let event_dec: TransactionEvent<()> = serde_json::from_str(exp).unwrap();
@@ -288,7 +270,7 @@ mod tests {
 			}));
 		let ser = serde_json::to_string(&event).unwrap();
 
-		let exp = r#"{"event":"bestChainBlockIncluded","block":{"hash":"0x0000000000000000000000000000000000000000000000000000000000000001","index":"2"}}"#;
+		let exp = r#"{"event":"bestChainBlockIncluded","block":{"hash":"0x0000000000000000000000000000000000000000000000000000000000000001","index":2}}"#;
 		assert_eq!(ser, exp);
 
 		let event_dec: TransactionEvent<H256> = serde_json::from_str(exp).unwrap();
@@ -303,7 +285,7 @@ mod tests {
 		});
 		let ser = serde_json::to_string(&event).unwrap();
 
-		let exp = r#"{"event":"finalized","block":{"hash":"0x0000000000000000000000000000000000000000000000000000000000000001","index":"10"}}"#;
+		let exp = r#"{"event":"finalized","block":{"hash":"0x0000000000000000000000000000000000000000000000000000000000000001","index":10}}"#;
 		assert_eq!(ser, exp);
 
 		let event_dec: TransactionEvent<H256> = serde_json::from_str(exp).unwrap();