Name changes for GrandPa and Beefy notifications protocols (#10463)

* grandpa: update notif protocol name

* grandpa: add chain id prefix to protocol name

* grandpa: beautify protocol name handling

* grandpa: prepend genesis hash to protocol name

* chain-spec: add optional 'fork_id'

'fork_id' is used to uniquely identify forks of the same chain/network
'ChainSpec' trait provides default 'None' implementation, meaning this
chain hasn't been forked.

* grandpa: protocol_name mod instead of struct

* beefy: add genesis hash prefix to protocol name

* chainspec: add fork_id

* grandpa: simplify protocol name

* grandpa: contain protocol name building logic

* beefy: contain protocol name building logic

* grandpa: fix tests

* fix merge damage

* fix docs reference visibility

Signed-off-by: acatangiu <adrian@parity.io>

* Update client/finality-grandpa/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update client/finality-grandpa/src/communication/mod.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update client/beefy/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update client/beefy/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* avoid using hash default, even for protocol names

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

substrate/client/beefy/src/lib.rs

@@ -39,15 +39,40 @@ mod round;
 mod worker;
 
 pub mod notification;
+pub use beefy_protocol_name::standard_name as protocol_standard_name;
 
-pub const BEEFY_PROTOCOL_NAME: &str = "/paritytech/beefy/1";
+pub(crate) mod beefy_protocol_name {
+	use sc_chain_spec::ChainSpec;
+
+	const NAME: &'static str = "/beefy/1";
+	/// Old names for the notifications protocol, used for backward compatibility.
+	pub(crate) const LEGACY_NAMES: [&'static str; 1] = ["/paritytech/beefy/1"];
+
+	/// Name of the notifications protocol used by BEEFY.
+	///
+	/// Must be registered towards the networking in order for BEEFY to properly function.
+	pub fn standard_name<Hash: std::fmt::Display>(
+		genesis_hash: &Hash,
+		chain_spec: &Box<dyn ChainSpec>,
+	) -> std::borrow::Cow<'static, str> {
+		let chain_prefix = match chain_spec.fork_id() {
+			Some(fork_id) => format!("/{}/{}", genesis_hash, fork_id),
+			None => format!("/{}", genesis_hash),
+		};
+		format!("{}{}", chain_prefix, NAME).into()
+	}
+}
 
 /// Returns the configuration value to put in
 /// [`sc_network::config::NetworkConfiguration::extra_sets`].
-pub fn beefy_peers_set_config() -> sc_network::config::NonDefaultSetConfig {
-	let mut cfg =
-		sc_network::config::NonDefaultSetConfig::new(BEEFY_PROTOCOL_NAME.into(), 1024 * 1024);
+/// For standard protocol name see [`beefy_protocol_name::standard_name`].
+pub fn beefy_peers_set_config(
+	protocol_name: std::borrow::Cow<'static, str>,
+) -> sc_network::config::NonDefaultSetConfig {
+	let mut cfg = sc_network::config::NonDefaultSetConfig::new(protocol_name, 1024 * 1024);
+
 	cfg.allow_non_reserved(25, 25);
+	cfg.add_fallback_names(beefy_protocol_name::LEGACY_NAMES.iter().map(|&n| n.into()).collect());
 	cfg
 }
 
@@ -101,6 +126,8 @@ where
 	pub min_block_delta: u32,
 	/// Prometheus metric registry
 	pub prometheus_registry: Option<Registry>,
+	/// Chain specific GRANDPA protocol name. See [`beefy_protocol_name::standard_name`].
+	pub protocol_name: std::borrow::Cow<'static, str>,
 }
 
 /// Start the BEEFY gadget.
@@ -122,11 +149,11 @@ where
 		signed_commitment_sender,
 		min_block_delta,
 		prometheus_registry,
+		protocol_name,
 	} = beefy_params;
 
 	let gossip_validator = Arc::new(gossip::GossipValidator::new());
-	let gossip_engine =
-		GossipEngine::new(network, BEEFY_PROTOCOL_NAME, gossip_validator.clone(), None);
+	let gossip_engine = GossipEngine::new(network, protocol_name, gossip_validator.clone(), None);
 
 	let metrics =
 		prometheus_registry.as_ref().map(metrics::Metrics::register).and_then(