implement web3_clientVersion (paritytech#7580)

Implements the `web3_clientVersion` method. This is a common requirement
for external Ethereum libraries when querying a client.

Fixes paritytech/contract-issues#26.

---------

Co-authored-by: cmd[bot] <41898282+github-actions[bot]@users.noreply.github.com>

prdoc/pr_7580.prdoc

@@ -0,0 +1,10 @@
+title: implement web3_clientVersion
+doc:
+- audience: Runtime Dev
+  description: |-
+    Implements the `web3_clientVersion`  method. This is a common requirement for external Ethereum libraries when querying a client.
+
+    Reference issue with more details: https://github.com/paritytech/contract-issues/issues/26.
+crates:
+- name: pallet-revive-eth-rpc
+  bump: minor

substrate/frame/revive/rpc/Cargo.toml

@@ -75,3 +75,6 @@ pretty_assertions = { workspace = true }
 static_init = { workspace = true }
 substrate-cli-test-utils = { workspace = true }
 subxt-signer = { workspace = true, features = ["unstable-eth"] }
+
+[build-dependencies]
+git2 = { version = "0.20.0", default-features = false }

substrate/frame/revive/rpc/build.rs

@@ -0,0 +1,44 @@
+// This file is part of Substrate.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+use std::process::Command;
+
+/// Get the current branch and commit hash.
+fn main() {
+	let output = Command::new("rustc")
+		.arg("--version")
+		.output()
+		.expect("cannot get the current rustc version");
+	// Exports the default rustc --version output:
+	// e.g. rustc 1.83.0 (90b35a623 2024-11-26)
+	// into the usual Ethereum web3_clientVersion format
+	// e.g. rustc1.83.0
+	let rustc_version = String::from_utf8_lossy(&output.stdout)
+		.split_whitespace()
+		.take(2)
+		.collect::<Vec<_>>()
+		.join("");
+	let target = std::env::var("TARGET").unwrap_or_else(|_| "unknown".to_string());
+
+	let repo = git2::Repository::open("../../../..").expect("should be a repository");
+	let head = repo.head().expect("should have head");
+	let commit = head.peel_to_commit().expect("should have commit");
+	let branch = head.shorthand().unwrap_or("unknown").to_string();
+	let id = &commit.id().to_string()[..7];
+	println!("cargo:rustc-env=GIT_REVISION={branch}-{id}");
+	println!("cargo:rustc-env=RUSTC_VERSION={rustc_version}");
+	println!("cargo:rustc-env=TARGET={target}");
+}

substrate/frame/revive/rpc/src/apis/execution_apis.rs

@@ -166,4 +166,8 @@ pub trait EthRpc {
 	/// The string value of current network id
 	#[method(name = "net_version")]
 	async fn net_version(&self) -> RpcResult<String>;
+
+	/// The string value of the current client version
+	#[method(name = "web3_clientVersion")]
+	async fn web3_client_version(&self) -> RpcResult<String>;
 }

substrate/frame/revive/rpc/src/lib.rs

@@ -352,4 +352,11 @@ impl EthRpcServer for EthRpcServerImpl {
 		let nonce = self.client.nonce(address, block).await?;
 		Ok(nonce)
 	}
+
+	async fn web3_client_version(&self) -> RpcResult<String> {
+		let git_revision = env!("GIT_REVISION");
+		let rustc_version = env!("RUSTC_VERSION");
+		let target = env!("TARGET");
+		Ok(format!("eth-rpc/{git_revision}/{target}/{rustc_version}"))
+	}
 }