GenesisConfig presets for runtime (#2714)

The runtime now can provide a number of predefined presets of
`RuntimeGenesisConfig` struct. This presets are intended to be used in
different deployments, e.g.: `local`, `staging`, etc, and should be
included into the corresponding chain-specs.

Having `GenesisConfig` presets in runtime allows to fully decouple node
from runtime types (the problem is described in #1984).

**Summary of changes:**
- The `GenesisBuilder` API was adjusted to enable this functionality
(and provide better naming - #150):
   ```rust
    fn preset_names() -> Vec<PresetId>;
fn get_preset(id: Option<PresetId>) -> Option<serde_json::Value>;
//`None` means default
    fn build_state(value: serde_json::Value);
    pub struct PresetId(Vec<u8>);
   ```

- **Breaking change**: Old `create_default_config` method was removed,
`build_config` was renamed to `build_state`. As a consequence a node
won't be able to interact with genesis config for older runtimes. The
cleanup was made for sake of API simplicity. Also IMO maintaining
compatibility with old API is not so crucial.
- Reference implementation was provided for `substrate-test-runtime` and
`rococo` runtimes. For rococo new
[`genesis_configs_presets`](https://github.com/paritytech/polkadot-sdk/blob/3b41d66b97c5ff0ec4a1989da5ffd8b9f3f588e3/polkadot/runtime/rococo/src/genesis_config_presets.rs#L530)
module was added and is used in `GenesisBuilder`
[_presets-related_](https://github.com/paritytech/polkadot-sdk/blob/3b41d66b97c5ff0ec4a1989da5ffd8b9f3f588e3/polkadot/runtime/rococo/src/lib.rs#L2462-L2485)
methods.

- The `chain-spec-builder` util was also improved and allows to
([_doc_](https://github.com/paritytech/polkadot-sdk/blob/3b41d66b97c5ff0ec4a1989da5ffd8b9f3f588e3/substrate/bin/utils/chain-spec-builder/src/lib.rs#L19)):
   - list presets provided by given runtime (`list-presets`),
- display preset or default config provided by the runtime
(`display-preset`),
   - build chain-spec using named preset (`create ... named-preset`),


- The `ChainSpecBuilder` is extended with
[`with_genesis_config_preset_name`](https://github.com/paritytech/polkadot-sdk/blob/3b41d66b97c5ff0ec4a1989da5ffd8b9f3f588e3/substrate/client/chain-spec/src/chain_spec.rs#L447)
method which allows to build chain-spec using named preset provided by
the runtime. Sample usage on the node side
[here](https://github.com/paritytech/polkadot-sdk/blob/2caffaae803e08a3d5b46c860e8016da023ff4ce/polkadot/node/service/src/chain_spec.rs#L404).

Implementation of #1984.
fixes: #150
part of: #25

---------

Co-authored-by: Sebastian Kunert <skunert49@gmail.com>
Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>
Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

substrate/client/chain-spec/src/chain_spec.rs

@@ -40,15 +40,26 @@ use std::{
 	sync::Arc,
 };
 
-#[derive(Serialize, Deserialize, Clone)]
+#[derive(Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
-enum GenesisBuildAction {
+enum GenesisBuildAction<EHF> {
 	Patch(json::Value),
 	Full(json::Value),
+	NamedPreset(String, PhantomData<EHF>),
+}
+
+impl<EHF> Clone for GenesisBuildAction<EHF> {
+	fn clone(&self) -> Self {
+		match self {
+			Self::Patch(ref p) => Self::Patch(p.clone()),
+			Self::Full(ref f) => Self::Full(f.clone()),
+			Self::NamedPreset(ref p, _) => Self::NamedPreset(p.clone(), Default::default()),
+		}
+	}
 }
 
 #[allow(deprecated)]
-enum GenesisSource<G> {
+enum GenesisSource<G, EHF> {
 	File(PathBuf),
 	Binary(Cow<'static, [u8]>),
 	/// factory function + code
@@ -56,10 +67,10 @@ enum GenesisSource<G> {
 	Factory(Arc<dyn Fn() -> G + Send + Sync>, Vec<u8>),
 	Storage(Storage),
 	/// build action + code
-	GenesisBuilderApi(GenesisBuildAction, Vec<u8>),
+	GenesisBuilderApi(GenesisBuildAction<EHF>, Vec<u8>),
 }
 
-impl<G> Clone for GenesisSource<G> {
+impl<G, EHF> Clone for GenesisSource<G, EHF> {
 	fn clone(&self) -> Self {
 		match *self {
 			Self::File(ref path) => Self::File(path.clone()),
@@ -71,7 +82,7 @@ impl<G> Clone for GenesisSource<G> {
 	}
 }
 
-impl<G: RuntimeGenesis> GenesisSource<G> {
+impl<G: RuntimeGenesis, EHF: HostFunctions> GenesisSource<G, EHF> {
 	fn resolve(&self) -> Result<Genesis<G>, String> {
 		/// helper container for deserializing genesis from the JSON file (ChainSpec JSON file is
 		/// also supported here)
@@ -118,6 +129,13 @@ impl<G: RuntimeGenesis> GenesisSource<G> {
 					json_blob: RuntimeGenesisConfigJson::Patch(patch.clone()),
 					code: code.clone(),
 				})),
+			Self::GenesisBuilderApi(GenesisBuildAction::NamedPreset(name, _), code) => {
+				let patch = RuntimeCaller::<EHF>::new(&code[..]).get_named_preset(Some(name))?;
+				Ok(Genesis::RuntimeGenesis(RuntimeGenesisInner {
+					json_blob: RuntimeGenesisConfigJson::Patch(patch),
+					code: code.clone(),
+				}))
+			},
 		}
 	}
 }
@@ -331,13 +349,13 @@ pub struct ChainSpecBuilder<G, E = NoExtension, EHF = ()> {
 	name: String,
 	id: String,
 	chain_type: ChainType,
-	genesis_build_action: GenesisBuildAction,
+	genesis_build_action: GenesisBuildAction<EHF>,
 	boot_nodes: Option<Vec<MultiaddrWithPeerId>>,
 	telemetry_endpoints: Option<TelemetryEndpoints>,
 	protocol_id: Option<String>,
 	fork_id: Option<String>,
 	properties: Option<Properties>,
-	_genesis: PhantomData<(G, EHF)>,
+	_genesis: PhantomData<G>,
 }
 
 impl<G, E, EHF> ChainSpecBuilder<G, E, EHF> {
@@ -425,6 +443,13 @@ impl<G, E, EHF> ChainSpecBuilder<G, E, EHF> {
 		self
 	}
 
+	/// Sets the name of runtime-provided JSON patch for runtime's GenesisConfig.
+	pub fn with_genesis_config_preset_name(mut self, name: &str) -> Self {
+		self.genesis_build_action =
+			GenesisBuildAction::NamedPreset(name.to_string(), Default::default());
+		self
+	}
+
 	/// Sets the full runtime's GenesisConfig JSON.
 	pub fn with_genesis_config(mut self, config: json::Value) -> Self {
 		self.genesis_build_action = GenesisBuildAction::Full(config);
@@ -463,7 +488,7 @@ impl<G, E, EHF> ChainSpecBuilder<G, E, EHF> {
 /// runtime is using the non-standard host function during genesis state creation.
 pub struct ChainSpec<G, E = NoExtension, EHF = ()> {
 	client_spec: ClientSpec<E>,
-	genesis: GenesisSource<G>,
+	genesis: GenesisSource<G, EHF>,
 	_host_functions: PhantomData<EHF>,
 }
 
@@ -1009,7 +1034,30 @@ mod tests {
 		assert!(raw_chain_spec.is_ok());
 	}
 
-	#[docify::export]
+	#[test]
+	fn generate_chain_spec_with_named_preset_works() {
+		sp_tracing::try_init_simple();
+		let output: ChainSpec<()> = ChainSpec::builder(
+			substrate_test_runtime::wasm_binary_unwrap().into(),
+			Default::default(),
+		)
+		.with_name("TestName")
+		.with_id("test_id")
+		.with_chain_type(ChainType::Local)
+		.with_genesis_config_preset_name("staging")
+		.build();
+
+		let actual = output.as_json(false).unwrap();
+		let expected =
+			from_str::<Value>(include_str!("../res/substrate_test_runtime_from_named_preset.json"))
+				.unwrap();
+
+		//wasm blob may change overtime so let's zero it. Also ensure it is there:
+		let actual = zeroize_code_key_in_json(false, actual.as_str());
+
+		assert_eq!(actual, expected);
+	}
+
 	#[test]
 	fn generate_chain_spec_with_patch_works() {
 		let output = ChainSpec::<()>::builder(
@@ -1089,6 +1137,8 @@ mod tests {
 
 	#[test]
 	fn chain_spec_as_json_fails_with_invalid_config() {
+		let expected_error_message =
+			include_str!("../res/chain_spec_as_json_fails_with_invalid_config.err");
 		let j =
 			include_str!("../../../test-utils/runtime/res/default_genesis_config_invalid_2.json");
 		let output = ChainSpec::<()>::builder(
@@ -1101,10 +1151,9 @@ mod tests {
 		.with_genesis_config(from_str(j).unwrap())
 		.build();
 
-		assert_eq!(
-			output.as_json(true),
-			Err("Invalid JSON blob: unknown field `babex`, expected one of `system`, `babe`, `substrateTest`, `balances` at line 1 column 8".to_string())
-		);
+		let result = output.as_json(true);
+
+		assert_eq!(result.err().unwrap(), expected_error_message);
 	}
 
 	#[test]