Struct zebra_node_services::mempool::TransactionDependencies

pub struct TransactionDependencies {
    dependencies: HashMap<Hash, HashSet<Hash>>,
    dependents: HashMap<Hash, HashSet<Hash>>,
}

Representation of mempool transactions’ dependencies on other transactions in the mempool.

Fields

dependencies: HashMap<Hash, HashSet<Hash>>

Lists of mempool transaction ids that create UTXOs spent by a mempool transaction. Used during block template construction to exclude transactions from block templates unless all of the transactions they depend on have been included.

dependents: HashMap<Hash, HashSet<Hash>>

Lists of transaction ids in the mempool that spend UTXOs created by a transaction in the mempool, e.g. tx1 -> set(tx2, tx3, tx4) where tx2, tx3, and tx4 spend outputs created by tx1.

Implementations

impl TransactionDependencies

pub fn add(&mut self, dependent: Hash, spent_mempool_outpoints: Vec<OutPoint>)

Adds a transaction that spends outputs created by other transactions in the mempool as a dependent of those transactions, and adds the transactions that created the outputs spent by the dependent transaction as dependencies of the dependent transaction.

Correctness

It’s the caller’s responsibility to ensure that there are no cyclical dependencies.

The transaction verifier will wait until the spent output of a transaction has been added to the verified set, so its AwaitOutput requests will timeout if there is a cyclical dependency.

pub fn clear_mined_dependencies(&mut self, mined_ids: &HashSet<Hash>)

Removes all dependents for a list of mined transaction ids and removes the mined transaction ids from the dependencies of their dependents.

pub fn remove_all(&mut self, tx_hash: &Hash) -> HashSet<Hash>

Removes the hash of a transaction in the mempool and the hashes of any transactions that are tracked as being directly or indirectly dependent on that transaction from this TransactionDependencies.

Returns a list of transaction hashes that were being tracked as dependents of the provided transaction hash.

pub fn direct_dependents(&self, tx_hash: &Hash) -> HashSet<Hash>

Returns a list of hashes of transactions that directly depend on the transaction for tx_hash.

pub fn direct_dependencies(&self, tx_hash: &Hash) -> HashSet<Hash>

Returns a list of hashes of transactions that are direct dependencies of the transaction for tx_hash.

pub fn clear(&mut self)

Clear the maps of transaction dependencies.

pub fn dependencies(&self) -> &HashMap<Hash, HashSet<Hash>>

Returns the map of transaction’s dependencies

pub fn dependents(&self) -> &HashMap<Hash, HashSet<Hash>>

Returns the map of transaction’s dependents

Trait Implementations

impl Clone for TransactionDependencies

fn clone(&self) -> TransactionDependencies

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TransactionDependencies

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for TransactionDependencies

fn default() -> TransactionDependencies

Returns the “default value” for a type.