From f4eb08dae5f844d75249bf773b04d311d00e73bf Mon Sep 17 00:00:00 2001
From: Sergey Pepyakin <s.pepyakin@gmail.com>
Date: Sat, 29 Sep 2018 18:56:00 +0100
Subject: [PATCH] Take and return the result in bytes (#842)

---
 substrate/core/rpc/src/state/mod.rs   | 17 ++++++++++++-----
 substrate/core/rpc/src/state/tests.rs |  2 +-
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/substrate/core/rpc/src/state/mod.rs b/substrate/core/rpc/src/state/mod.rs
index 0e90198ffa..ff5404460d 100644
--- a/substrate/core/rpc/src/state/mod.rs
+++ b/substrate/core/rpc/src/state/mod.rs
@@ -27,7 +27,7 @@ use jsonrpc_macros::pubsub;
 use jsonrpc_pubsub::SubscriptionId;
 use primitives::hexdisplay::HexDisplay;
 use primitives::storage::{StorageKey, StorageData, StorageChangeSet};
-use primitives::{Blake2Hasher};
+use primitives::{Blake2Hasher, Bytes};
 use rpc::Result as RpcResult;
 use rpc::futures::{stream, Future, Sink, Stream};
 use runtime_primitives::generic::BlockId;
@@ -49,7 +49,7 @@ build_rpc_trait! {
 
 		/// Call a contract at a block's state.
 		#[rpc(name = "state_call", alias = ["state_callAt", ])]
-		fn call(&self, String, Vec<u8>, Trailing<Hash>) -> Result<Vec<u8>>;
+		fn call(&self, String, Bytes, Trailing<Hash>) -> Result<Bytes>;
 
 		/// Returns a storage entry at a specific block's state.
 		#[rpc(name = "state_getStorage", alias = ["state_getStorageAt", ])]
@@ -121,10 +121,17 @@ impl<B, E, Block> StateApi<Block::Hash> for State<B, E, Block> where
 {
 	type Metadata = ::metadata::Metadata;
 
-	fn call(&self, method: String, data: Vec<u8>, block: Trailing<Block::Hash>) -> Result<Vec<u8>> {
+	fn call(&self, method: String, data: Bytes, block: Trailing<Block::Hash>) -> Result<Bytes> {
 		let block = self.unwrap_or_best(block)?;
-		trace!(target: "rpc", "Calling runtime at {:?} for method {} ({})", block, method, HexDisplay::from(&data));
-		Ok(self.client.executor().call(&BlockId::Hash(block), &method, &data)?.return_data)
+		trace!(target: "rpc", "Calling runtime at {:?} for method {} ({})", block, method, HexDisplay::from(&data.0));
+		let return_data = self.client
+			.executor()
+			.call(
+				&BlockId::Hash(block),
+				&method, &data.0
+			)?
+			.return_data;
+		Ok(Bytes(return_data))
 	}
 
 	fn storage(&self, key: StorageKey, block: Trailing<Block::Hash>) -> Result<Option<StorageData>> {
diff --git a/substrate/core/rpc/src/state/tests.rs b/substrate/core/rpc/src/state/tests.rs
index bad934b840..8c401ec1bb 100644
--- a/substrate/core/rpc/src/state/tests.rs
+++ b/substrate/core/rpc/src/state/tests.rs
@@ -43,7 +43,7 @@ fn should_call_contract() {
 	let client = State::new(client, core.executor());
 
 	assert_matches!(
-		client.call("balanceOf".into(), vec![1,2,3], Some(genesis_hash).into()),
+		client.call("balanceOf".into(), Bytes(vec![1,2,3]), Some(genesis_hash).into()),
 		Err(Error(ErrorKind::Client(client::error::ErrorKind::Execution(_)), _))
 	)
 }