feat(katana): node config builder

[kariy]

Problem

we have a main config struct that encapsulates bunch of other smaller configs. this config struct is then passed to the katana_node::build() method.

dojo/crates/katana/node/src/config/mod.rs

Lines 16 to 28 in 884a726

	/// Node configurations.
	///
	/// List of all possible options that can be used to configure a node.
	#[derive(Debug, Clone, Default)]
	pub struct Config {
	/// The chain specification.
	pub chain: ChainSpec,
	/// Database options.
	pub db: DbConfig,
	/// Forking options.

dojo/crates/katana/node/src/lib.rs

Lines 157 to 163 in 884a726

	/// Build the node components from the given [`Config`].
	///
	/// This returns a [`Node`] instance which can be launched with the all the necessary components
	/// configured.
	pub async fn build(mut config: Config) -> Result<Node> {
	if config.metrics.is_some() {
	// Metrics recorder must be initialized before calling any of the metrics macros, in order

because there are many configurations, it can be quite a hassle to specify each one of them. especially when you only want to specify some of them and want to use the default values for the rest. for example, in the dojo-test-utils:

dojo/crates/dojo/test-utils/src/sequencer.rs

Lines 114 to 122 in 884a726

	pub fn get_default_test_config(sequencing: SequencingConfig) -> Config {
	let dev = DevConfig { fee: false, account_validation: true, fixed_gas_prices: None };
	let mut chain = ChainSpec { id: ChainId::SEPOLIA, ..Default::default() };
	chain.genesis.sequencer_address = *DEFAULT_SEQUENCER_ADDRESS;
	let rpc = RpcConfig {
	allowed_origins: None,
	port: 0,

---

it'd be nice to have a ConfigBuilder where you can set individual values using the builder pattern. the logic for the katana_node::build() can then be moved to ConfigBuilder::build() method.

[edisontim]

Hey! Would be down to work on this!