How to change the native token in Substrate to a custom token?

Question

I want create a custom token in Substrate by the name GGG and I want to use this token for each transaction fee instead of the default Substrate token. Can someone please guide me on how to change the native token in Substrate to my custom token GGG?

Answer 1

All you need to do is set a custom property for token symbol in the chainspec.rs file in the function where you generate the chainspec config. This is typically a function that goes by the name of development_config in the substrate node template. Here I've done it:

let mut props = Properties::new();

props.insert("tokenSymbol".into(), "FYR".into()); 

props.insert("tokenDecimals".into(), "6".into());

And then finally attach it to the ChainSpec props field :

Ok(ChainSpec::from_genesis( 
     // Name
     "Development", 
     // ID 
      "dev", 
      ChainType::Development, 
                 move || { 
                         testnet_genesis( 
                                 wasm_binary, 
                                 // Initial PoA authorities 
                                 vec![authority_keys_from_seed("Alice")], 
                                 // Sudo account 
                                 get_account_id_from_seed::<sr25519::Public>("Alice"), 
                                 // Pre-funded accounts 
                                 vec![ 
                                         get_account_id_from_seed::<sr25519::Public>("Alice"), 
                                         get_account_id_from_seed::<sr25519::Public>("Bob"), 
                                         get_account_id_from_seed::<sr25519::Public>("Alice//stash"), 
                                         get_account_id_from_seed::<sr25519::Public>("Bob//stash"), 
                                 ], 
                                 true, 
                         ) 
                 }, 
                 // Bootnodes 
                 vec![], 
                 // Telemetry 
                 None, 
                 // Protocol ID 
                 None, 
                 None, 
                 // Properties (*Attach your props here*)
                 Some(props), 
                 // Extensions 
                 None, 
         ))

Answer 2

You can create a function like this:

https://github.com/darwinia-network/darwinia/blob/2d1c1436594b2c397d450e317c35eb16c71105d6/node/service/src/chain_spec/darwinia.rs#L52-L61

Replace the names and the decimals with yours.

One more thing, this could be a Vec. So, you can register multiple tokens at one time. As my example shows, our chain has 2 native tokens.

---

Then pass it to your genesis:

https://github.com/darwinia-network/darwinia/blob/2d1c1436594b2c397d450e317c35eb16c71105d6/node/service/src/chain_spec/darwinia.rs#L334