Make runtime_io::chain_id configurable

[xlc]

I think it currently returns hardcoded 42. It should be configurable in chain spec.

substrate/core/state-machine/src/basic.rs

Line 171 in 7dd7067

fn chain_id(&self) -> u64 { 42 }

But there is also another id in chain spec, which is a string.

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

Line 111 in 7dd7067

pub id: String,

[ayushmishra2005]

@xlc I checked the latest codebase. I couldn't find core directory. Can you please guide me? I want to pick this task.

[xlc]

It is now here

substrate/primitives/state-machine/src/basic.rs

Line 264 in 1845278

fn chain_id(&self) -> u64 { 42 }

[ayushmishra2005]

@xlc I debugged a bit. I found that this file is related to Types and traits related to chain specifications

substrate/primitives/chain-spec/src/lib.rs

Line 18 in c60f008

//! Types and traits related to chain specifications.

Should I defined chain_id as Constant here ?

substrate/primitives/core/src/crypto.rs

Line 56 in c60f008

[xlc]

Make it a constant is definitely not the intent of this issue because that won't make it configurable by any means.

However I don't actually know how should we make it configurable and if even we need this field or not.

If you just want to contribute something simple, I highly recommend to pick something else. We need someone to actually define how should we improve this first before any coding.

[gui1117]

as a note BasicExternalities is only used:

to build genesis storage in

substrate/frame/support/procedural/src/storage/genesis_config/mod.rs

Line 157 in c60f008

#scrate::BasicExternalities::execute_with_storage(storage, || {

and to get runtime version:

substrate/primitives/io/src/lib.rs

Line 397 in c60f008

let mut ext = sp_state_machine::BasicExternalities::default();

but indeed it should either be unavailable or return the correct value I think

[athei]

Closed by #7810. One should use the following as chain id:

substrate/frame/system/src/lib.rs

Lines 261 to 266 in 0fc8329

	/// The designated SS85 prefix of this chain.
	///
	/// This replaces the "ss58Format" property declared in the chain spec. Reason is
	/// that the runtime should know about the prefix in order to make use of it as
	/// an identifier of the chain.
	type SS58Prefix: Get<u8>;