pallet-utxo

Utxo support, based on Substrate's workshop.

This is only the pallet; no node and runtime implementation.

To run the test cases, just run command cargo test.

How to run the benchmark in mintlayer-node:

1. Insert this pallet-utxo crate in pallets directory.

2. At runtime's Cargo.toml:
   2.1. add to local dependencies:

   pallet-utxo = { default-features = false, path = "../pallets/utxo" }

   2.2. add to runtime-benchmarks features:

   'pallet-utxo/runtime-benchmarks'

   2.3. add to std features:

   'pallet-utxo/std'

3. At runtime's lib.rs:
   3.1. Import the following:

   pub use pallet_utxo;
   use sp_runtime::transaction_validity::{TransactionValidityError, InvalidTransaction};
   use sp_core::H256;
   use frame_support::traits::IsSubType;

   3.2. Add the utxo config:

   impl pallet_utxo::Config for Runtime {
       type Event = Event;
       type Call = Call;
       type WeightInfo = pallet_utxo::weights::WeightInfo<Runtime>;
   
       fn authorities() -> Vec<H256> {
           Aura::authorities()
               .iter()
               .map(|x| {
                   let r: &sp_core::sr25519::Public = x.as_ref();
                   r.0.into()
               })
               .collect()
      }
   }

   3.3. Add into construct_runtime! this line:

   Utxo: pallet_utxo::{Pallet, Call, Config<T>, Storage, Event<T>},

   3.4. inside fn validate_transaction(), add this code before the Executive::validate_transaction(source, tx) line:

   if let Some(pallet_utxo::Call::spend(ref tx)) = 
        IsSubType::<pallet_utxo::Call::<Runtime>>::is_sub_type(&tx.function) {
            match pallet_utxo::validate_transaction::<Runtime>(&tx) {
                Ok(valid_tx) => { return Ok(valid_tx); }
                Err(_) => {
                    return Err(TransactionValidityError::Invalid(InvalidTransaction::Custom(1)));
                }
            }
        }

   3.5. In the function fn dispatch_benchmark(), add another line:

   add_benchmark!(params, batches, pallet_utxo, Utxo);

4. In node's chain_spec.rs:
   4.1. Import the ff:

   use node_template_runtime::{UtxoConfig, pallet_utxo};
   use sp_core:H256;

   4.2. add one more param on function testnet_genesis():

   endowed_utxos: Vec<sr25519::Public>

   4.3. inside function testnet_genesis(), create the genesis utxo:

   let genesis:Vec<pallet_utxo::TransactionOutput> = endowed_utxos.iter().map(|x| {
       let pub_key = H256::from_slice(x.as_slice());
       let tx_output = pallet_utxo::TransactionOutput::new(
           100 as pallet_utxo::Value,
           pub_key
       );
   
       let blake_hash = BlakeTwo256::hash_of(&tx_output);
     
       tx_output
   }).collect();

   4.4. Still inside testnet_genesis() function, add to the GenesisConfig:

   pallet_utxo: UtxoConfig {
               genesis_utxos: genesis,
               _marker: Default::default()
           }

   4.5. Inside both fn development_config() and fn local_testnet_config(), add the missing param of testnet_genesis() for the endowed_utxos:

   vec![
        get_from_seed::<sr25519::Public>("Alice"),
        get_account_id_from_seed::<sr25519::Public>("Bob")
   ]

5. On the terminal, move to the node directory and run

   cargo b --release --features runtime-benchmarks

6. Go back to the workspace directory $> cd .. and run:

    RUST_LOG=runtime=debug 
    target/release/node-template benchmark 
    --chain dev 
    --execution=wasm 
    --wasm-execution=compiled 
    --pallet pallet_utxo 
    --extrinsic runtime_spend 
    --steps 20 
    --repeat 10 
    --output . 
    --raw