Rename ExportGenesisStateCommand to ExportGenesisHeadCommand and …

…make it respect custom genesis block builders (#2331)

Closes #2326.

This PR both fixes a logic bug and replaces an incorrect name.

## Bug Fix: Respecting custom genesis builder

Prior to this PR the standard logic for creating a genesis block was
repeated inside of cumulus. This PR removes that duplicated logic, and
calls into the proper `BuildGenesisBlock` implementation.

One consequence is that if the genesis block has already been
initialized, it will not be re-created, but rather read from the
database like it is for other node invocations. So you need to watch out
for old unpurged data during the development process. Offchain tools may
need to be updated accordingly. I've already filed
paritytech/zombienet#1519

## Rename: It doesn't export state. It exports head data.

The name export-genesis-state was always wrong, nad it's never too late
to right a wrong. I've changed the name of the struct to
`ExportGenesisHeadCommand`.

There is still the question of what to do with individual nodes' public
CLIs. I have updated the parachain template to a reasonable default that
preserves compatibility with tools that will expect
`export-genesis-state` to still work. And I've chosen not to modify the
public CLIs of any other nodes in the repo. I'll leave it up to their
individual owners/maintains to decide whether that is appropriate.

---------

Co-authored-by: Joshy Orndorff <[email protected]>
Co-authored-by: Bastian Köcher <[email protected]>
Co-authored-by: Bastian Köcher <[email protected]>

cumulus/client/cli/Cargo.toml

@@ -18,3 +18,4 @@ sc-chain-spec = { path = "../../../substrate/client/chain-spec" }
 sc-service = { path = "../../../substrate/client/service" }
 sp-core = { path = "../../../substrate/primitives/core" }
 sp-runtime = { path = "../../../substrate/primitives/runtime" }
+sp-blockchain = { path = "../../../substrate/primitives/blockchain" }

cumulus/client/cli/src/lib.rs

@@ -23,20 +23,18 @@ use std::{
 	io::{self, Write},
 	net::SocketAddr,
 	path::PathBuf,
+	sync::Arc,
 };
 
 use codec::Encode;
 use sc_chain_spec::ChainSpec;
-use sc_client_api::ExecutorProvider;
+use sc_client_api::HeaderBackend;
 use sc_service::{
 	config::{PrometheusConfig, TelemetryEndpoints},
 	BasePath, TransactionPoolOptions,
 };
 use sp_core::hexdisplay::HexDisplay;
-use sp_runtime::{
-	traits::{Block as BlockT, Hash as HashT, Header as HeaderT, Zero},
-	StateVersion,
-};
+use sp_runtime::traits::{Block as BlockT, Zero};
 use url::Url;
 
 /// The `purge-chain` command used to remove the whole chain: the parachain and the relay chain.
@@ -129,9 +127,9 @@ impl sc_cli::CliConfiguration for PurgeChainCmd {
 	}
 }
 
-/// Command for exporting the genesis state of the parachain
+/// Command for exporting the genesis head data of the parachain
 #[derive(Debug, clap::Parser)]
-pub struct ExportGenesisStateCommand {
+pub struct ExportGenesisHeadCommand {
 	/// Output file name or stdout if unspecified.
 	#[arg()]
 	pub output: Option<PathBuf>,
@@ -145,24 +143,29 @@ pub struct ExportGenesisStateCommand {
 	pub shared_params: sc_cli::SharedParams,
 }
 
-impl ExportGenesisStateCommand {
-	/// Run the export-genesis-state command
-	pub fn run<Block: BlockT>(
-		&self,
-		chain_spec: &dyn ChainSpec,
-		client: &impl ExecutorProvider<Block>,
-	) -> sc_cli::Result<()> {
-		let state_version = sc_chain_spec::resolve_state_version_from_wasm(
-			&chain_spec.build_storage()?,
-			client.executor(),
-		)?;
-
-		let block: Block = generate_genesis_block(chain_spec, state_version)?;
-		let raw_header = block.header().encode();
+impl ExportGenesisHeadCommand {
+	/// Run the export-genesis-head command
+	pub fn run<B, C>(&self, client: Arc<C>) -> sc_cli::Result<()>
+	where
+		B: BlockT,
+		C: HeaderBackend<B> + 'static,
+	{
+		let genesis_hash = client.hash(Zero::zero())?.ok_or(sc_cli::Error::Client(
+			sp_blockchain::Error::Backend(
+				"Failed to lookup genesis block hash when exporting genesis head data.".into(),
+			),
+		))?;
+		let genesis_header = client.header(genesis_hash)?.ok_or(sc_cli::Error::Client(
+			sp_blockchain::Error::Backend(
+				"Failed to lookup genesis header by hash when exporting genesis head data.".into(),
+			),
+		))?;
+
+		let raw_header = genesis_header.encode();
 		let output_buf = if self.raw {
 			raw_header
 		} else {
-			format!("0x{:?}", HexDisplay::from(&block.header().encode())).into_bytes()
+			format!("0x{:?}", HexDisplay::from(&genesis_header.encode())).into_bytes()
 		};
 
 		if let Some(output) = &self.output {
@@ -175,43 +178,7 @@ impl ExportGenesisStateCommand {
 	}
 }
 
-/// Generate the genesis block from a given ChainSpec.
-pub fn generate_genesis_block<Block: BlockT>(
-	chain_spec: &dyn ChainSpec,
-	genesis_state_version: StateVersion,
-) -> Result<Block, String> {
-	let storage = chain_spec.build_storage()?;
-
-	let child_roots = storage.children_default.iter().map(|(sk, child_content)| {
-		let state_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
-			child_content.data.clone().into_iter().collect(),
-			genesis_state_version,
-		);
-		(sk.clone(), state_root.encode())
-	});
-	let state_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
-		storage.top.clone().into_iter().chain(child_roots).collect(),
-		genesis_state_version,
-	);
-
-	let extrinsics_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
-		Vec::new(),
-		genesis_state_version,
-	);
-
-	Ok(Block::new(
-		<<Block as BlockT>::Header as HeaderT>::new(
-			Zero::zero(),
-			extrinsics_root,
-			state_root,
-			Default::default(),
-			Default::default(),
-		),
-		Default::default(),
-	))
-}
-
-impl sc_cli::CliConfiguration for ExportGenesisStateCommand {
+impl sc_cli::CliConfiguration for ExportGenesisHeadCommand {
 	fn shared_params(&self) -> &sc_cli::SharedParams {
 		&self.shared_params
 	}

cumulus/parachain-template/node/src/cli.rs

@@ -24,8 +24,11 @@ pub enum Subcommand {
 	/// Remove the whole chain.
 	PurgeChain(cumulus_client_cli::PurgeChainCmd),
 
-	/// Export the genesis state of the parachain.
-	ExportGenesisState(cumulus_client_cli::ExportGenesisStateCommand),
+	/// Export the genesis head data of the parachain.
+	///
+	/// Head data is the encoded block header.
+	#[command(alias = "export-genesis-state")]
+	ExportGenesisHead(cumulus_client_cli::ExportGenesisHeadCommand),
 
 	/// Export the genesis wasm of the parachain.
 	ExportGenesisWasm(cumulus_client_cli::ExportGenesisWasmCommand),

cumulus/parachain-template/node/src/command.rs

@@ -162,12 +162,12 @@ pub fn run() -> Result<()> {
 				cmd.run(config, polkadot_config)
 			})
 		},
-		Some(Subcommand::ExportGenesisState(cmd)) => {
+		Some(Subcommand::ExportGenesisHead(cmd)) => {
 			let runner = cli.create_runner(cmd)?;
 			runner.sync_run(|config| {
 				let partials = new_partial(&config)?;
 
-				cmd.run(&*config.chain_spec, &*partials.client)
+				cmd.run(partials.client)
 			})
 		},
 		Some(Subcommand::ExportGenesisWasm(cmd)) => {

cumulus/polkadot-parachain/src/cli.rs

@@ -45,7 +45,8 @@ pub enum Subcommand {
 	PurgeChain(cumulus_client_cli::PurgeChainCmd),
 
 	/// Export the genesis state of the parachain.
-	ExportGenesisState(cumulus_client_cli::ExportGenesisStateCommand),
+	#[command(alias = "export-genesis-state")]
+	ExportGenesisHead(cumulus_client_cli::ExportGenesisHeadCommand),
 
 	/// Export the genesis wasm of the parachain.
 	ExportGenesisWasm(cumulus_client_cli::ExportGenesisWasmCommand),

cumulus/polkadot-parachain/src/command.rs

@@ -530,10 +530,10 @@ pub fn run() -> Result<()> {
 				cmd.run(config, polkadot_config)
 			})
 		},
-		Some(Subcommand::ExportGenesisState(cmd)) => {
+		Some(Subcommand::ExportGenesisHead(cmd)) => {
 			let runner = cli.create_runner(cmd)?;
 			runner.sync_run(|config| {
-				construct_partials!(config, |partials| cmd.run(&*config.chain_spec, &*partials.client))
+				construct_partials!(config, |partials| cmd.run(partials.client))
 			})
 		},
 		Some(Subcommand::ExportGenesisWasm(cmd)) => {

cumulus/test/service/src/cli.rs

@@ -16,6 +16,7 @@
 
 use std::{net::SocketAddr, path::PathBuf};
 
+use cumulus_client_cli::{ExportGenesisHeadCommand, ExportGenesisWasmCommand};
 use polkadot_service::{ChainSpec, ParaId, PrometheusConfig};
 use sc_cli::{
 	CliConfiguration, DefaultConfigurationValues, ImportParams, KeystoreParams, NetworkParams,
@@ -60,45 +61,13 @@ pub enum Subcommand {
 	BuildSpec(sc_cli::BuildSpecCmd),
 
 	/// Export the genesis state of the parachain.
-	ExportGenesisState(ExportGenesisStateCommand),
+	#[command(alias = "export-genesis-state")]
+	ExportGenesisHead(ExportGenesisHeadCommand),
 
 	/// Export the genesis wasm of the parachain.
 	ExportGenesisWasm(ExportGenesisWasmCommand),
 }
 
-#[derive(Debug, clap::Parser)]
-#[group(skip)]
-pub struct ExportGenesisStateCommand {
-	#[arg(default_value_t = 2000u32)]
-	pub parachain_id: u32,
-
-	#[command(flatten)]
-	pub base: cumulus_client_cli::ExportGenesisStateCommand,
-}
-
-impl CliConfiguration for ExportGenesisStateCommand {
-	fn shared_params(&self) -> &SharedParams {
-		&self.base.shared_params
-	}
-}
-
-/// Command for exporting the genesis wasm file.
-#[derive(Debug, clap::Parser)]
-#[group(skip)]
-pub struct ExportGenesisWasmCommand {
-	#[arg(default_value_t = 2000u32)]
-	pub parachain_id: u32,
-
-	#[command(flatten)]
-	pub base: cumulus_client_cli::ExportGenesisWasmCommand,
-}
-
-impl CliConfiguration for ExportGenesisWasmCommand {
-	fn shared_params(&self) -> &SharedParams {
-		&self.base.shared_params
-	}
-}
-
 #[derive(Debug)]
 pub struct RelayChainCli {
 	/// The actual relay chain cli object.

cumulus/test/service/src/genesis.rs

@@ -15,11 +15,50 @@
 // along with Cumulus.  If not, see <http://www.gnu.org/licenses/>.
 
 use codec::Encode;
-use cumulus_client_cli::generate_genesis_block;
 use cumulus_primitives_core::ParaId;
 use cumulus_test_runtime::Block;
 use polkadot_primitives::HeadData;
-use sp_runtime::traits::Block as BlockT;
+use sc_chain_spec::ChainSpec;
+use sp_runtime::{
+	traits::{Block as BlockT, Hash as HashT, Header as HeaderT, Zero},
+	StateVersion,
+};
+
+/// Generate a simple test genesis block from a given ChainSpec.
+pub fn generate_genesis_block<Block: BlockT>(
+	chain_spec: &dyn ChainSpec,
+	genesis_state_version: StateVersion,
+) -> Result<Block, String> {
+	let storage = chain_spec.build_storage()?;
+
+	let child_roots = storage.children_default.iter().map(|(sk, child_content)| {
+		let state_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
+			child_content.data.clone().into_iter().collect(),
+			genesis_state_version,
+		);
+		(sk.clone(), state_root.encode())
+	});
+	let state_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
+		storage.top.clone().into_iter().chain(child_roots).collect(),
+		genesis_state_version,
+	);
+
+	let extrinsics_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
+		Vec::new(),
+		genesis_state_version,
+	);
+
+	Ok(Block::new(
+		<<Block as BlockT>::Header as HeaderT>::new(
+			Zero::zero(),
+			extrinsics_root,
+			state_root,
+			Default::default(),
+			Default::default(),
+		),
+		Default::default(),
+	))
+}
 
 /// Returns the initial head data for a parachain ID.
 pub fn initial_head_data(para_id: ParaId) -> HeadData {

cumulus/test/service/src/lib.rs

@@ -22,7 +22,9 @@
 pub mod bench_utils;
 
 pub mod chain_spec;
-mod genesis;
+
+/// Utilities for creating test genesis block and head data
+pub mod genesis;
 
 use runtime::AccountId;
 use sc_executor::{HeapAllocStrategy, WasmExecutor, DEFAULT_HEAP_ALLOC_STRATEGY};

cumulus/test/service/src/main.rs

@@ -16,16 +16,14 @@
 
 mod cli;
 
-use std::{io::Write, sync::Arc};
+use std::sync::Arc;
 
 use cli::{RelayChainCli, Subcommand, TestCollatorCli};
-use cumulus_client_cli::generate_genesis_block;
 use cumulus_primitives_core::{relay_chain::CollatorPair, ParaId};
-use cumulus_test_service::AnnounceBlockFn;
+use cumulus_test_service::{new_partial, AnnounceBlockFn};
 use polkadot_service::runtime_traits::AccountIdConversion;
 use sc_cli::{CliConfiguration, SubstrateCli};
-use sp_core::{hexdisplay::HexDisplay, Encode, Pair};
-use sp_runtime::traits::Block;
+use sp_core::Pair;
 
 pub fn wrap_announce_block() -> Box<dyn FnOnce(AnnounceBlockFn) -> AnnounceBlockFn> {
 	tracing::info!("Block announcements disabled.");
@@ -44,38 +42,16 @@ fn main() -> Result<(), sc_cli::Error> {
 			runner.sync_run(|config| cmd.run(config.chain_spec, config.network))
 		},
 
-		Some(Subcommand::ExportGenesisState(params)) => {
-			let mut builder = sc_cli::LoggerBuilder::new("");
-			builder.with_profiling(sc_tracing::TracingReceiver::Log, "");
-			let _ = builder.init();
-
-			let spec =
-				cli.load_spec(&params.base.shared_params.chain.clone().unwrap_or_default())?;
-			let state_version = cumulus_test_service::runtime::VERSION.state_version();
-
-			let block: parachains_common::Block = generate_genesis_block(&*spec, state_version)?;
-			let raw_header = block.header().encode();
-			let output_buf = if params.base.raw {
-				raw_header
-			} else {
-				format!("0x{:?}", HexDisplay::from(&block.header().encode())).into_bytes()
-			};
-
-			if let Some(output) = &params.base.output {
-				std::fs::write(output, output_buf)?;
-			} else {
-				std::io::stdout().write_all(&output_buf)?;
-			}
-
-			Ok(())
+		Some(Subcommand::ExportGenesisHead(cmd)) => {
+			let runner = cli.create_runner(cmd)?;
+			runner.sync_run(|mut config| {
+				let partial = new_partial(&mut config, false)?;
+				cmd.run(partial.client)
+			})
 		},
 		Some(Subcommand::ExportGenesisWasm(cmd)) => {
 			let runner = cli.create_runner(cmd)?;
-			runner.sync_run(|_config| {
-				let parachain_id = ParaId::from(cmd.parachain_id);
-				let spec = cumulus_test_service::get_chain_spec(Some(parachain_id));
-				cmd.base.run(&spec)
-			})
+			runner.sync_run(|config| cmd.run(&*config.chain_spec))
 		},
 		None => {
 			let log_filters = cli.run.normalize().log_filters();

polkadot/parachain/test-parachains/adder/collator/src/cli.rs

@@ -24,16 +24,16 @@ use sc_cli::SubstrateCli;
 pub enum Subcommand {
 	/// Export the genesis state of the parachain.
 	#[command(name = "export-genesis-state")]
-	ExportGenesisState(ExportGenesisStateCommand),
+	ExportGenesisState(ExportGenesisHeadCommand),
 
 	/// Export the genesis wasm of the parachain.
 	#[command(name = "export-genesis-wasm")]
 	ExportGenesisWasm(ExportGenesisWasmCommand),
 }
 
-/// Command for exporting the genesis state of the parachain
+/// Command for exporting the genesis head data of the parachain
 #[derive(Debug, Parser)]
-pub struct ExportGenesisStateCommand {}
+pub struct ExportGenesisHeadCommand {}
 
 /// Command for exporting the genesis wasm file.
 #[derive(Debug, Parser)]