Files
tycho-protocol-sdk/substreams/crates/tycho-substreams/src/contract.rs

230 lines
9.0 KiB
Rust

/// Helpers to extract relevant contract storage.
///
/// This file contains helpers to capture contract changes from the expanded block
/// model. These leverage the `code_changes`, `balance_changes`, and `storage_changes`
/// fields available on the `Call` type provided by block model in a substream
/// (i.e. `logs_and_calls`, etc).
///
/// ## Warning
/// ⚠️ These helpers *only* work if the **extended block model** is available,
/// more [here](https://streamingfastio.medium.com/new-block-model-to-accelerate-chain-integration-9f65126e5425)
use std::collections::HashMap;
use substreams_ethereum::pb::eth::{
self,
v2::{block::DetailLevel, CallType, StorageChange},
};
use crate::pb::tycho::evm::v1::{self as tycho};
struct SlotValue {
new_value: Vec<u8>,
start_value: Vec<u8>,
}
impl From<&StorageChange> for SlotValue {
fn from(change: &StorageChange) -> Self {
Self { new_value: change.new_value.clone(), start_value: change.old_value.clone() }
}
}
impl SlotValue {
fn has_changed(&self) -> bool {
self.start_value != self.new_value
}
}
// Uses a map for slots, protobuf does not allow bytes in hashmap keys
struct InterimContractChange {
address: Vec<u8>,
balance: Vec<u8>,
code: Vec<u8>,
slots: HashMap<Vec<u8>, SlotValue>,
change: tycho::ChangeType,
}
impl InterimContractChange {
fn new(address: &[u8], creation: bool) -> Self {
Self {
address: address.to_vec(),
balance: vec![],
code: vec![],
slots: Default::default(),
change: if creation { tycho::ChangeType::Creation } else { tycho::ChangeType::Update },
}
}
}
impl From<InterimContractChange> for tycho::ContractChange {
fn from(value: InterimContractChange) -> Self {
tycho::ContractChange {
address: value.address,
balance: value.balance,
code: value.code,
slots: value
.slots
.into_iter()
.filter(|(_, value)| value.has_changed())
.map(|(slot, value)| tycho::ContractSlot { slot, value: value.new_value })
.collect(),
change: value.change.into(),
}
}
}
/// Extracts and aggregates contract changes from a block.
///
/// This function identifies and collects changes to contract storage, code, and native balance for
/// contracts of interest within a given block. It filters contracts based on a user-defined
/// predicate and aggregates changes into a provided mutable map.
///
/// ## Arguments
/// * `block` - The block from which to extract contract changes, expected to be an extended block
/// model.
/// * `inclusion_predicate` - A closure that determines if a contract's address is of interest for
/// the collection of changes. Only contracts satisfying this predicate are included.
/// * `transaction_contract_changes` - A mutable reference to a map where extracted contract changes
/// are stored. Keyed by transaction index, it aggregates changes into
/// `tycho::TransactionContractChanges`.
///
/// ## Panics
/// Panics if the provided block is not an extended block model, as indicated by its detail level.
///
/// ## Operation
/// The function iterates over transactions and their calls within the block, collecting contract
/// changes (storage, balance, code) that pass the inclusion predicate. Changes are then sorted by
/// their ordinals to maintain the correct sequence of events. Aggregated changes for each contract
/// are stored in `transaction_contract_changes`, categorized by transaction index.
///
/// Contracts created within the block are tracked to differentiate between new and existing
/// contracts. The aggregation process respects transaction boundaries, ensuring that changes are
/// mapped accurately to their originating transactions.
pub fn extract_contract_changes<F: Fn(&[u8]) -> bool>(
block: &eth::v2::Block,
inclusion_predicate: F,
transaction_contract_changes: &mut HashMap<u64, tycho::TransactionContractChanges>,
) {
if block.detail_level != Into::<i32>::into(DetailLevel::DetaillevelExtended) {
panic!("Only extended blocks are supported");
}
let mut changed_contracts: HashMap<Vec<u8>, InterimContractChange> = HashMap::new();
// Collect all accounts created in this block
let created_accounts: HashMap<_, _> = block
.transactions()
.flat_map(|tx| {
tx.calls.iter().flat_map(|call| {
call.account_creations
.iter()
.map(|ac| (&ac.account, ac.ordinal))
})
})
.collect();
block
.transactions()
.for_each(|block_tx| {
let mut storage_changes = Vec::new();
let mut balance_changes = Vec::new();
let mut code_changes = Vec::new();
let filtered_calls = block_tx.calls.iter().filter(|call| {
let address_included = inclusion_predicate(&call.address);
let caller_included = inclusion_predicate(&call.caller);
let is_delegate_or_callcode = call.call_type() == CallType::Delegate ||
call.call_type() == CallType::Callcode;
!call.state_reverted &&
(address_included || (caller_included && is_delegate_or_callcode))
});
filtered_calls.for_each(|call| {
storage_changes.extend(call.storage_changes.iter());
balance_changes.extend(call.balance_changes.iter());
code_changes.extend(call.code_changes.iter());
});
storage_changes.sort_unstable_by_key(|change| change.ordinal);
balance_changes.sort_unstable_by_key(|change| change.ordinal);
code_changes.sort_unstable_by_key(|change| change.ordinal);
storage_changes
.iter()
.filter(|changes| inclusion_predicate(&changes.address))
.for_each(|&storage_change| {
let contract_change = changed_contracts
.entry(storage_change.address.clone())
.or_insert_with(|| {
InterimContractChange::new(
&storage_change.address,
created_accounts.contains_key(&storage_change.address),
)
});
let slot_value = contract_change
.slots
.entry(storage_change.key.clone())
.or_insert_with(|| storage_change.into());
slot_value
.new_value
.copy_from_slice(&storage_change.new_value);
});
balance_changes
.iter()
.filter(|changes| inclusion_predicate(&changes.address))
.for_each(|balance_change| {
let contract_change = changed_contracts
.entry(balance_change.address.clone())
.or_insert_with(|| {
InterimContractChange::new(
&balance_change.address,
created_accounts.contains_key(&balance_change.address),
)
});
if let Some(new_balance) = &balance_change.new_value {
contract_change.balance.clear();
contract_change
.balance
.extend_from_slice(&new_balance.bytes);
}
});
code_changes
.iter()
.filter(|changes| inclusion_predicate(&changes.address))
.for_each(|code_change| {
let contract_change = changed_contracts
.entry(code_change.address.clone())
.or_insert_with(|| {
InterimContractChange::new(
&code_change.address,
created_accounts.contains_key(&code_change.address),
)
});
contract_change.code.clear();
contract_change
.code
.extend_from_slice(&code_change.new_code);
});
if !storage_changes.is_empty() ||
!balance_changes.is_empty() ||
!code_changes.is_empty()
{
transaction_contract_changes
.entry(block_tx.index.into())
.or_insert_with(|| tycho::TransactionContractChanges::new(&(block_tx.into())))
.contract_changes
.extend(
changed_contracts
.drain()
.map(|(_, change)| change.into()),
);
}
});
}