refactor(mempool)!: match server/v2/cometbft and sdk mempool interface (#21744)

Co-authored-by: Marko <marko@baricevic.me>

server/v2/cometbft/mempool/mempool.go

@@ -19,13 +19,18 @@ type Mempool[T transaction.Tx] interface {
 	Insert(context.Context, T) error
 
 	// Select returns an Iterator over the app-side mempool. If txs are specified,
-	// then they shall be incorporated into the Iterator. The Iterator must be
-	// closed by the caller.
+	// then they shall be incorporated into the Iterator. The Iterator is not thread-safe to use.
 	Select(context.Context, []T) Iterator[T]
 
+	// SelectBy use callback to iterate over the mempool, it's thread-safe to use.
+	SelectBy(context.Context, []T, func(T) bool)
+
+	// CountTx returns the number of transactions currently in the mempool.
+	CountTx() int
+
 	// Remove attempts to remove a transaction from the mempool, returning an error
 	// upon failure.
-	Remove([]T) error
+	Remove(T) error
 }
 
 // Iterator defines an app-side mempool iterator interface that is as minimal as

server/v2/cometbft/mempool/noop.go

@@ -4,8 +4,11 @@ import (
 	"context"
 
 	"cosmossdk.io/core/transaction"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
 )
 
+var _ Mempool[sdk.Tx] = (*NoOpMempool[sdk.Tx])(nil) // verify interface at compile time
 var _ Mempool[transaction.Tx] = (*NoOpMempool[transaction.Tx])(nil)
 
 // NoOpMempool defines a no-op mempool. Transactions are completely discarded and
@@ -16,7 +19,8 @@ var _ Mempool[transaction.Tx] = (*NoOpMempool[transaction.Tx])(nil)
 // is FIFO-ordered by default.
 type NoOpMempool[T transaction.Tx] struct{}
 
-func (NoOpMempool[T]) Insert(context.Context, T) error         { return nil }
-func (NoOpMempool[T]) Select(context.Context, []T) Iterator[T] { return nil }
-func (NoOpMempool[T]) CountTx() int                            { return 0 }
-func (NoOpMempool[T]) Remove([]T) error                        { return nil }
+func (NoOpMempool[T]) Insert(context.Context, T) error             { return nil }
+func (NoOpMempool[T]) Select(context.Context, []T) Iterator[T]     { return nil }
+func (NoOpMempool[T]) SelectBy(context.Context, []T, func(T) bool) {}
+func (NoOpMempool[T]) CountTx() int                                { return 0 }
+func (NoOpMempool[T]) Remove(T) error                              { return nil }