btcd/mempool
Olaoluwa Osuntokun dec3e41354 deps+log: upgrade to btclog/v2 with dual logger support
This commit upgrades the btclog dependency from v0 to support both v1 and
v2 loggers simultaneously. The dual logger pattern, inspired by LND's
implementation, allows us to incrementally adopt btclog/v2's structured
logging capabilities in the mempool subsystem while maintaining backward
compatibility with the rest of the codebase.

The key changes enable structured logging (DebugS, InfoS, WarnS, etc.) with
key-value pair attributes for rich operational context, particularly valuable
for security monitoring and debugging in the mempool implementation.

We create separate backends: backendLog using btclogv1 for existing
subsystems, and backendLogV2 using btclog v2 for the mempool. The
setLogLevel function now handles both logger types via type switching,
ensuring log level changes work across both versions.
2025-10-27 16:10:29 -07:00
..
txgraph mempool: implement orphan management and query methods 2025-10-03 18:53:27 -07:00
doc.go chore: fix some typos in comments (#2164) 2024-04-26 08:08:05 -04:00
error.go blockchain: Combine ErrDoubleSpend & ErrMissingTx. 2017-08-14 11:40:39 -05:00
estimatefee.go mempool: add interface compliance checks for OrphanManager and FeeEstimator 2025-10-03 16:51:17 -07:00
estimatefee_test.go multi: Run gofmt on the entire repository 2023-06-21 22:31:09 +09:00
interface.go mempool+rpcserver: add interface TxMempool 2024-01-15 17:22:41 +08:00
log.go deps+log: upgrade to btclog/v2 with dual logger support 2025-10-27 16:10:29 -07:00
mempool.go mempool: refactor TxPool to use extracted validation helpers 2025-10-03 16:46:39 -07:00
mempool_test.go multi: map btcd mempool acceptance errors to bitcoind's testmempoolaccept 2024-01-15 17:22:41 +08:00
mempool_v2.go mempool: implement orphan management and query methods 2025-10-03 18:53:27 -07:00
mempool_v2_ops_test.go mempool/test: improve orphan promotion test coverage 2025-10-03 18:54:00 -07:00
mempool_v2_query_test.go mempool/test: add comprehensive query method tests 2025-10-03 18:54:40 -07:00
mempool_v2_test.go mempool/test: complete basic mempool method tests 2025-10-03 18:54:18 -07:00
mocks.go rpcserver+mempool: implement gettxspendingprevout for btcd 2024-02-27 22:58:33 +08:00
orphan.go mempool: fix orphan processing to accept parent transaction 2025-10-03 18:51:50 -07:00
orphan_test.go mempool: fix orphan processing to accept parent transaction 2025-10-03 18:51:50 -07:00
policy.go mempool: extract validation helpers to policy.go for reuse 2025-10-03 16:46:04 -07:00
policy_enforcer.go mempool: expand PolicyEnforcer interface for complete validation 2025-10-03 16:50:44 -07:00
policy_enforcer_test.go mempool: expand PolicyEnforcer interface for complete validation 2025-10-03 16:50:44 -07:00
policy_test.go btcec+mempool: delete minor unreachable code caused by t.Fatal 2024-10-08 15:09:20 +02:00
README.md chore: fix typos 2024-03-29 10:21:29 +08:00
tx_validator.go mempool: add TxValidator interface and StandardTxValidator 2025-10-03 16:47:06 -07:00
validation_v2.go mempool: implement checkMempoolAcceptance using TxValidator 2025-10-03 16:48:10 -07:00

mempool

Build Status ISC License GoDoc

Package mempool provides a policy-enforced pool of unmined bitcoin transactions.

A key responsibility of the bitcoin network is mining user-generated transactions into blocks. In order to facilitate this, the mining process relies on having a readily-available source of transactions to include in a block that is being solved.

At a high level, this package satisfies that requirement by providing an in-memory pool of fully validated transactions that can also optionally be further filtered based upon a configurable policy.

One of the policy configuration options controls whether or not "standard" transactions are accepted. In essence, a "standard" transaction is one that satisfies a fairly strict set of requirements that are largely intended to help provide fair use of the system to all users. It is important to note that what is considered a "standard" transaction changes over time. For some insight, at the time of this writing, an example of some of the criteria that are required for a transaction to be considered standard are that it is of the most-recently supported version, finalized, does not exceed a specific size, and only consists of specific script forms.

Since this package does not deal with other bitcoin specifics such as network communication and transaction relay, it returns a list of transactions that were accepted which gives the caller a high level of flexibility in how they want to proceed. Typically, this will involve things such as relaying the transactions to other peers on the network and notifying the mining process that new transactions are available.

This package has intentionally been designed so it can be used as a standalone package for any projects needing the ability create an in-memory pool of bitcoin transactions that are not only valid by consensus rules, but also adhere to a configurable policy.

Feature Overview

The following is a quick overview of the major features. It is not intended to be an exhaustive list.

  • Maintain a pool of fully validated transactions
    • Reject non-fully-spent duplicate transactions
    • Reject coinbase transactions
    • Reject double spends (both from the chain and other transactions in pool)
    • Reject invalid transactions according to the network consensus rules
    • Full script execution and validation with signature cache support
    • Individual transaction query support
  • Orphan transaction support (transactions that spend from unknown outputs)
    • Configurable limits (see transaction acceptance policy)
    • Automatic addition of orphan transactions that are no longer orphans as new transactions are added to the pool
    • Individual orphan transaction query support
  • Configurable transaction acceptance policy
    • Option to accept or reject standard transactions
    • Option to accept or reject transactions based on priority calculations
    • Rate limiting of low-fee and free transactions
    • Non-zero fee threshold
    • Max signature operations per transaction
    • Max orphan transaction size
    • Max number of orphan transactions allowed
  • Additional metadata tracking for each transaction
    • Timestamp when the transaction was added to the pool
    • Most recent block height when the transaction was added to the pool
    • The fee the transaction pays
    • The starting priority for the transaction
  • Manual control of transaction removal
    • Recursive removal of all dependent transactions

Installation and Updating

$ go get -u github.com/btcsuite/btcd/mempool

License

Package mempool is licensed under the copyfree ISC License.