Add dev_getBlockStats RPC (#10939)

* Add chain_getBlockStats rpc

* Fix broken doc link

* Apply suggestions from code review

Co-authored-by: Niklas Adolfsson <niklasadolfsson1@gmail.com>

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

* fmt

* Fix compilation

* Move Blockstats

* Apply suggestions from code review

Co-authored-by: David <dvdplm@gmail.com>

* fmt

Co-authored-by: ascjones <ascjones@gmail.com>
Co-authored-by: Niklas Adolfsson <niklasadolfsson1@gmail.com>
Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>
Co-authored-by: David <dvdplm@gmail.com>

substrate/client/rpc-api/src/dev/error.rs

@@ -0,0 +1,71 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2022 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program 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.
+
+// This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! Error helpers for Dev RPC module.
+
+use crate::errors;
+use jsonrpc_core as rpc;
+
+/// Dev RPC Result type.
+pub type Result<T> = std::result::Result<T, Error>;
+
+/// Dev RPC future Result type.
+pub type FutureResult<T> = jsonrpc_core::BoxFuture<Result<T>>;
+
+/// Dev RPC errors.
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+	/// Failed to query specified block or its parent: Probably an invalid hash.
+	#[error("Error while querying block: {0}")]
+	BlockQueryError(Box<dyn std::error::Error + Send>),
+	/// The re-execution of the specified block failed.
+	#[error("Failed to re-execute the specified block")]
+	BlockExecutionFailed,
+	/// The witness compaction failed.
+	#[error("Failed to create to compact the witness")]
+	WitnessCompactionFailed,
+	/// The method is marked as unsafe but unsafe flag wasn't supplied on the CLI.
+	#[error(transparent)]
+	UnsafeRpcCalled(#[from] crate::policy::UnsafeRpcError),
+}
+
+/// Base error code for all dev errors.
+const BASE_ERROR: i64 = 6000;
+
+impl From<Error> for rpc::Error {
+	fn from(e: Error) -> Self {
+		match e {
+			Error::BlockQueryError(_) => rpc::Error {
+				code: rpc::ErrorCode::ServerError(BASE_ERROR + 1),
+				message: e.to_string(),
+				data: None,
+			},
+			Error::BlockExecutionFailed => rpc::Error {
+				code: rpc::ErrorCode::ServerError(BASE_ERROR + 3),
+				message: e.to_string(),
+				data: None,
+			},
+			Error::WitnessCompactionFailed => rpc::Error {
+				code: rpc::ErrorCode::ServerError(BASE_ERROR + 4),
+				message: e.to_string(),
+				data: None,
+			},
+			e => errors::internal(e),
+		}
+	}
+}

substrate/client/rpc-api/src/dev/mod.rs

@@ -0,0 +1,64 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2022 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program 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.
+
+// This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! Substrate dev API containing RPCs that are mainly meant for debugging and stats collection for
+//! developers. The endpoints in this RPC module are not meant to be available to non-local users
+//! and are all marked `unsafe`.
+
+pub mod error;
+
+use self::error::Result;
+use codec::{Decode, Encode};
+use jsonrpc_derive::rpc;
+use scale_info::TypeInfo;
+use serde::{Deserialize, Serialize};
+
+/// Statistics of a block returned by the `dev_getBlockStats` RPC.
+#[derive(Eq, PartialEq, Clone, Copy, Encode, Decode, Debug, TypeInfo, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct BlockStats {
+	/// The length in bytes of the storage proof produced by executing the block.
+	pub witness_len: u64,
+	/// The length in bytes of the storage proof after compaction.
+	pub witness_compact_len: u64,
+	/// Length of the block in bytes.
+	///
+	/// This information can also be acquired by downloading the whole block. This merely
+	/// saves some complexity on the client side.
+	pub block_len: u64,
+	/// Number of extrinsics in the block.
+	///
+	/// This information can also be acquired by downloading the whole block. This merely
+	/// saves some complexity on the client side.
+	pub num_extrinsics: u64,
+}
+
+/// Substrate dev API.
+///
+/// This API contains unstable and unsafe methods only meant for development nodes. They
+/// are all flagged as unsafe for this reason.
+#[rpc]
+pub trait DevApi<Hash> {
+	/// Reexecute the specified `block_hash` and gather statistics while doing so.
+	///
+	/// This function requires the specified block and its parent to be available
+	/// at the queried node. If either the specified block or the parent is pruned,
+	/// this function will return `None`.
+	#[rpc(name = "dev_getBlockStats")]
+	fn block_stats(&self, block_hash: Hash) -> Result<Option<BlockStats>>;
+}

substrate/client/rpc-api/src/lib.rs

@@ -35,6 +35,7 @@ pub use policy::{DenyUnsafe, UnsafeRpcError};
 pub mod author;
 pub mod chain;
 pub mod child_state;
+pub mod dev;
 pub mod offchain;
 pub mod state;
 pub mod system;