chainHead: Remove chainHead_genesis method (#2296)

The method has been removed from the spec
(https://github.com/paritytech/json-rpc-interface-spec/tree/main/src),
this PR keeps the `chainHead` in sync with that change.

@paritytech/subxt-team

---------

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>

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

@@ -74,14 +74,6 @@ pub trait ChainHeadApi<Hash> {
 		hash: Hash,
 	) -> RpcResult<Option<String>>;
 
-	/// Get the chain's genesis hash.
-	///
-	/// # Unstable
-	///
-	/// This method is unstable and subject to change in the future.
-	#[method(name = "chainHead_unstable_genesisHash", blocking)]
-	fn chain_head_unstable_genesis_hash(&self) -> RpcResult<String>;
-
 	/// Returns storage entries at a specific block's state.
 	///
 	/// # Unstable

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

@@ -107,8 +107,6 @@ pub struct ChainHead<BE: Backend<Block>, Block: BlockT, Client> {
 	executor: SubscriptionTaskExecutor,
 	/// Keep track of the pinned blocks for each subscription.
 	subscriptions: Arc<SubscriptionManagement<Block, BE>>,
-	/// The hexadecimal encoded hash of the genesis block.
-	genesis_hash: String,
 	/// The maximum number of items reported by the `chainHead_storage` before
 	/// pagination is required.
 	operation_max_storage_items: usize,
@@ -118,14 +116,12 @@ pub struct ChainHead<BE: Backend<Block>, Block: BlockT, Client> {
 
 impl<BE: Backend<Block>, Block: BlockT, Client> ChainHead<BE, Block, Client> {
 	/// Create a new [`ChainHead`].
-	pub fn new<GenesisHash: AsRef<[u8]>>(
+	pub fn new(
 		client: Arc<Client>,
 		backend: Arc<BE>,
 		executor: SubscriptionTaskExecutor,
-		genesis_hash: GenesisHash,
 		config: ChainHeadConfig,
 	) -> Self {
-		let genesis_hash = hex_string(&genesis_hash.as_ref());
 		Self {
 			client,
 			backend: backend.clone(),
@@ -137,7 +133,6 @@ impl<BE: Backend<Block>, Block: BlockT, Client> ChainHead<BE, Block, Client> {
 				backend,
 			)),
 			operation_max_storage_items: config.operation_max_storage_items,
-			genesis_hash,
 			_phantom: PhantomData,
 		}
 	}
@@ -315,10 +310,6 @@ where
 			.map_err(Into::into)
 	}
 
-	fn chain_head_unstable_genesis_hash(&self) -> RpcResult<String> {
-		Ok(self.genesis_hash.clone())
-	}
-
 	fn chain_head_unstable_storage(
 		&self,
 		follow_subscription: String,

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

@@ -28,7 +28,7 @@ use futures::Future;
 use jsonrpsee::{
 	core::{error::Error, server::rpc_module::Subscription as RpcSubscription},
 	rpc_params,
-	types::{error::CallError, EmptyServerParams as EmptyParams},
+	types::error::CallError,
 	RpcModule,
 };
 use sc_block_builder::BlockBuilderBuilder;
@@ -61,7 +61,6 @@ const MAX_PINNED_BLOCKS: usize = 32;
 const MAX_PINNED_SECS: u64 = 60;
 const MAX_OPERATIONS: usize = 16;
 const MAX_PAGINATION_LIMIT: usize = 5;
-const CHAIN_GENESIS: [u8; 32] = [0; 32];
 const INVALID_HASH: [u8; 32] = [1; 32];
 const KEY: &[u8] = b":mock";
 const VALUE: &[u8] = b"hello world";
@@ -111,7 +110,6 @@ async fn setup_api() -> (
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -162,7 +160,6 @@ async fn follow_subscription_produces_blocks() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -231,7 +228,6 @@ async fn follow_with_runtime() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -345,31 +341,6 @@ async fn follow_with_runtime() {
 	assert_eq!(event, expected);
 }
 
-#[tokio::test]
-async fn get_genesis() {
-	let builder = TestClientBuilder::new();
-	let backend = builder.backend();
-	let client = Arc::new(builder.build());
-
-	let api = ChainHead::new(
-		client.clone(),
-		backend,
-		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
-		ChainHeadConfig {
-			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
-			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
-			subscription_max_ongoing_operations: MAX_OPERATIONS,
-			operation_max_storage_items: MAX_PAGINATION_LIMIT,
-		},
-	)
-	.into_rpc();
-
-	let genesis: String =
-		api.call("chainHead_unstable_genesisHash", EmptyParams::new()).await.unwrap();
-	assert_eq!(genesis, hex_string(&CHAIN_GENESIS));
-}
-
 #[tokio::test]
 async fn get_header() {
 	let (_client, api, _sub, sub_id, block) = setup_api().await;
@@ -569,7 +540,6 @@ async fn call_runtime_without_flag() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -1228,7 +1198,6 @@ async fn separate_operation_ids_for_subscriptions() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -1316,7 +1285,6 @@ async fn follow_generates_initial_blocks() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -1472,7 +1440,6 @@ async fn follow_exceeding_pinned_blocks() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: 2,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -1549,7 +1516,6 @@ async fn follow_with_unpin() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: 2,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -1815,7 +1781,6 @@ async fn follow_prune_best_block() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -2001,7 +1966,6 @@ async fn follow_forks_pruned_block() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -2153,7 +2117,6 @@ async fn follow_report_multiple_pruned_block() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -2399,7 +2362,6 @@ async fn pin_block_references() {
 		client.clone(),
 		backend.clone(),
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: 3,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -2537,7 +2499,6 @@ async fn follow_finalized_before_new_block() {
 		client_mock.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -2652,7 +2613,6 @@ async fn ensure_operation_limits_works() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -2757,7 +2717,6 @@ async fn check_continue_operation() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),
@@ -2940,7 +2899,6 @@ async fn stop_storage_operation() {
 		client.clone(),
 		backend,
 		Arc::new(TaskExecutor::default()),
-		CHAIN_GENESIS,
 		ChainHeadConfig {
 			global_max_pinned_blocks: MAX_PINNED_BLOCKS,
 			subscription_max_pinned_duration: Duration::from_secs(MAX_PINNED_SECS),