mirror of
https://github.com/btcsuite/btcd.git
synced 2024-11-19 09:50:08 +01:00
ba5407615d
The doc formatting changes introduced in the recent go version is increasing the diff for all of the new commits. Formatting it all in this commit will help the readability of future PRs by reducing the diff.
82 lines
4.2 KiB
Go
82 lines
4.2 KiB
Go
// Copyright (c) 2016 The btcsuite developers
|
|
// Use of this source code is governed by an ISC
|
|
// license that can be found in the LICENSE file.
|
|
|
|
/*
|
|
Package mempool provides a policy-enforced pool of unmined bitcoin transactions.
|
|
|
|
A key responsbility 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.
|
|
|
|
# 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
|
|
1. Reject non-fully-spent duplicate transactions
|
|
2. Reject coinbase transactions
|
|
3. Reject double spends (both from the chain and other transactions in pool)
|
|
4. Reject invalid transactions according to the network consensus rules
|
|
5. Full script execution and validation with signature cache support
|
|
6. Individual transaction query support
|
|
- Orphan transaction support (transactions that spend from unknown outputs)
|
|
1. Configurable limits (see transaction acceptance policy)
|
|
2. Automatic addition of orphan transactions that are no longer orphans as new
|
|
transactions are added to the pool
|
|
3. Individual orphan transaction query support
|
|
- Configurable transaction acceptance policy
|
|
1. Option to accept or reject standard transactions
|
|
2. Option to accept or reject transactions based on priority calculations
|
|
3. Rate limiting of low-fee and free transactions
|
|
4. Non-zero fee threshold
|
|
5. Max signature operations per transaction
|
|
6. Max orphan transaction size
|
|
7. Max number of orphan transactions allowed
|
|
- Additional metadata tracking for each transaction
|
|
1. Timestamp when the transaction was added to the pool
|
|
2. Most recent block height when the transaction was added to the pool
|
|
3. The fee the transaction pays
|
|
4. The starting priority for the transaction
|
|
- Manual control of transaction removal
|
|
1. Recursive removal of all dependent transactions
|
|
|
|
# Errors
|
|
|
|
Errors returned by this package are either the raw errors provided by underlying
|
|
calls or of type mempool.RuleError. Since there are two classes of rules
|
|
(mempool acceptance rules and blockchain (consensus) acceptance rules), the
|
|
mempool.RuleError type contains a single Err field which will, in turn, either
|
|
be a mempool.TxRuleError or a blockchain.RuleError. The first indicates a
|
|
violation of mempool acceptance rules while the latter indicates a violation of
|
|
consensus acceptance rules. This allows the caller to easily differentiate
|
|
between unexpected errors, such as database errors, versus errors due to rule
|
|
violations through type assertions. In addition, callers can programmatically
|
|
determine the specific rule violation by type asserting the Err field to one of
|
|
the aforementioned types and examining their underlying ErrorCode field.
|
|
*/
|
|
package mempool
|