Add Latest State TransactionValidator implementation

[mattsse]

Describe the feature

the transaction pool requires a TransactionValidator

reth/crates/transaction-pool/src/validate.rs

Line 30 in afb6671

pub trait TransactionValidator: Send + Sync {

which is supposed to validate the transaction against protocol specs and the latest state.

It returns an outcome that includes the latest nonce and balance

reth/crates/transaction-pool/src/validate.rs

Lines 15 to 19 in afb6671

	Valid {
	/// Balance of the sender at the current point.
	balance: U256,
	/// Current nonce of the sender.
	state_nonce: u64,

TODO

• Add an implementation of this that takes an AccountProvider and implements basic transaction checks

Additional context

No response

[chirag-bgh]

I can take this.

[seroze]

@mattsse just to cross check my understanding.

which is supposed to validate the transaction against protocol specs and the latest state.

we have to fetch the latest state of the sender account and verify if the current_balance >= transaction_amount and if txn_nonce matches with last_txn_nonce+1. Are there any more checks that Iam missing ?

Add an implementation of this that takes an AccountProvider and implements basic transaction checks

How do we fetch the latest state of Account. I couldn't find any class with name AccountProvider ? Is the expectation to implement this class as well ?

[mattsse]

couldn't find any class with name AccountProvider

this is not fully implemented yet, but we abstract everything over the traits so all impls should be generic over the traits.

we have to fetch the latest state of the sender account and verify if the current_balance >= transaction_amount and if txn_nonce matches with last_txn_nonce+1.

not necessarily, we need to fetch current balance and nonce which is then used by the pool to update internals.
but we need to ensure nonce > last_txn_nonce because nonce < last_txn_nonce would be invalid.

[chirag-bgh]

@mattsse for what type should be the trait TransactionValidator implemented?

[mattsse]

It should be something like

pub struct EthTransactionValidator<Client: AccountPorivider> {
   /// This type fetches account info from the db
   client: Client,
   /// whether shanghai is enabled.
   shanghai: bool,
}