`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/3b41d66b/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/3b41d66b/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/3b41d66b/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/3b41d66b/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/2caffaae /polkadot/node/service/src/chain_spec.rs#L404). Implementation of #1984. fixes: #150 part of: #25 --------- Co-authored-by: Sebastian Kunert <[email protected]> Co-authored-by: Kian Paimani <[email protected]> Co-authored-by: Oliver Tale-Yazdi <[email protected]>