feat(txpool): add PoolStatus Api (#91)

crates/transaction-pool/src/lib.rs

@@ -84,7 +84,7 @@ pub use crate::{
 use crate::{
     error::PoolResult,
     pool::PoolInner,
-    traits::{NewTransactionEvent, TransactionOrigin},
+    traits::{NewTransactionEvent, PoolStatus, TransactionOrigin},
     validate::ValidPoolTransaction,
 };
 use futures::channel::mpsc::Receiver;
@@ -174,6 +174,10 @@ where
 {
     type Transaction = T::Transaction;
 
+    fn status(&self) -> PoolStatus {
+        self.pool.status()
+    }
+
     async fn on_new_block(&self, _event: NewBlockEvent) {
         // TODO perform maintenance: update pool accordingly
         todo!()

crates/transaction-pool/src/pool/mod.rs

@@ -67,7 +67,7 @@ use crate::{
     error::PoolResult,
     identifier::{SenderId, SenderIdentifiers, TransactionId},
     pool::{listener::PoolEventListener, state::SubPool, txpool::TxPool},
-    traits::{NewTransactionEvent, PoolTransaction, TransactionOrigin},
+    traits::{NewTransactionEvent, PoolStatus, PoolTransaction, TransactionOrigin},
     validate::{TransactionValidationOutcome, ValidPoolTransaction},
     PoolConfig, TransactionOrdering, TransactionValidator, U256,
 };
@@ -126,6 +126,11 @@ where
         }
     }
 
+    /// Returns stats about the pool.
+    pub(crate) fn status(&self) -> PoolStatus {
+        self.pool.read().status()
+    }
+
     /// Returns the internal `SenderId` for this address
     pub(crate) fn get_sender_id(&self, addr: Address) -> SenderId {
         self.identifiers.write().sender_id_or_create(addr)

crates/transaction-pool/src/pool/txpool.rs

@@ -10,6 +10,7 @@ use crate::{
         state::{SubPool, TxState},
         AddedPendingTransaction, AddedTransaction,
     },
+    traits::PoolStatus,
     PoolConfig, PoolResult, PoolTransaction, TransactionOrdering, ValidPoolTransaction, U256,
 };
 use fnv::FnvHashMap;
@@ -97,6 +98,16 @@ impl<T: TransactionOrdering> TxPool<T> {
             config,
         }
     }
+
+    /// Returns stats about the pool.
+    pub(crate) fn status(&self) -> PoolStatus {
+        PoolStatus {
+            pending: self.pending_pool.len(),
+            basefee: self.basefee_pool.len(),
+            queued: self.queued_pool.len(),
+        }
+    }
+
     /// Updates the pool based on the changed base fee.
     ///
     /// This enforces the dynamic fee requirement.

crates/transaction-pool/src/traits.rs

@@ -13,6 +13,9 @@ pub trait TransactionPool: Send + Sync + 'static {
     /// The transaction type of the pool
     type Transaction: PoolTransaction;
 
+    /// Returns stats about the pool.
+    fn status(&self) -> PoolStatus;
+
     /// Event listener for when a new block was mined.
     ///
     /// Implementers need to update the pool accordingly.
@@ -189,3 +192,14 @@ pub trait PoolTransaction: fmt::Debug + Send + Sync + 'static {
     /// This will return `None` for non-EIP1559 transactions
     fn max_priority_fee_per_gas(&self) -> Option<U256>;
 }
+
+/// Represents the current status of the pool.
+#[derive(Debug, Clone)]
+pub struct PoolStatus {
+    /// Number of transactions in the _pending_ sub-pool.
+    pub pending: usize,
+    /// Number of transactions in the _basefee_ pool.
+    pub basefee: usize,
+    /// Number of transactions in the _queued_ sub-pool.
+    pub queued: usize,
+}