lbcd/blockchain
Josh Rickmar a6965d493f all: Remove seelog logger.
The btclog package has been changed to defining its own logging
interface (rather than seelog's) and provides a default implementation
for callers to use.

There are two primary advantages to the new logger implementation.

First, all log messages are created before the call returns.  Compared
to seelog, this prevents data races when mutable variables are logged.

Second, the new logger does not implement any kind of artifical rate
limiting (what seelog refers to as "adaptive logging").  Log messages
are outputted as soon as possible and the application will appear to
perform much better when watching standard output.

Because log rotation is not a feature of the btclog logging
implementation, it is handled by the main package by importing a file
rotation package that provides an io.Reader interface for creating
output to a rotating file output.  The rotator has been configured
with the same defaults that btcd previously used in the seelog config
(10MB file limits with maximum of 3 rolls) but now compresses newly
created roll files.  Due to the high compressibility of log text, the
compressed files typically reduce to around 15-30% of the original
10MB file.
2017-06-19 16:46:50 -04:00
..
fullblocktests multi: Update markdown files for GFM changes. 2017-05-25 12:06:16 -05:00
indexers multi: Update markdown files for GFM changes. 2017-05-25 12:06:16 -05:00
testdata blockchain: Rework to use new db interface. 2016-04-11 16:47:27 -05:00
accept.go blockchain: Refactor main block index logic. 2017-02-01 13:14:41 -06:00
bench_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
blockindex.go blockchain: Use hash values in structs. 2017-02-03 11:36:33 -06:00
blocklocator.go blockchain: Use hash values in structs. 2017-02-03 11:36:33 -06:00
chain.go blockchain: enforce CSV soft-fork validation based on versionbits state 2017-05-10 15:37:11 -07:00
chain_test.go rpctest: Make subpackage of integration. 2017-05-11 15:17:29 -05:00
chainio.go blockchain: Use hash values in structs. 2017-02-03 11:36:33 -06:00
chainio_test.go chainhash: Abstract hash logic to new package. (#729) 2016-08-08 14:04:33 -05:00
checkpoints.go multi: Improvements to configurable checkpoints. 2017-01-23 12:07:54 -06:00
common_test.go blockchain: Allow adding additional checkpoints 2017-01-18 23:56:43 +01:00
compress.go blockchain: Rework to use new db interface. 2016-04-11 16:47:27 -05:00
compress_test.go blockchain: Rework to use new db interface. 2016-04-11 16:47:27 -05:00
difficulty.go blockchain: Refactor main block index logic. 2017-02-01 13:14:41 -06:00
difficulty_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
doc.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
error.go Implement infrastructure for BIP0009. 2016-11-30 13:51:59 -06:00
error_test.go Implement infrastructure for BIP0009. 2016-11-30 13:51:59 -06:00
example_test.go blockchain: Expose main chain flag on ProcessBlock. 2016-10-13 16:47:50 -05:00
fullblocks_test.go blockchain: Use hash values in structs. 2017-02-03 11:36:33 -06:00
internal_test.go blockchain: Use int64 timestamps in block nodes. 2017-01-31 17:51:29 -06:00
log.go all: Remove seelog logger. 2017-06-19 16:46:50 -04:00
mediantime.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
mediantime_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
merkle.go chainhash: Abstract hash logic to new package. (#729) 2016-08-08 14:04:33 -05:00
merkle_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
notifications.go blockchain: Rework to use new db interface. 2016-04-11 16:47:27 -05:00
process.go blockchain: Ignore side chains in exists check. 2017-02-03 11:02:35 -06:00
README.md multi: Update markdown files for GFM changes. 2017-05-25 12:06:16 -05:00
reorganization_test.go multi: Improvements to configurable checkpoints. 2017-01-23 12:07:54 -06:00
scriptval.go multi: Simplify code per gosimple linter. 2016-11-03 13:00:35 -05:00
scriptval_test.go blockchain: make scriptval_test fail more nicely 2016-09-16 15:44:27 -04:00
thresholdstate.go Fix a ton of typos accumulated over time 2017-05-30 16:59:51 +02:00
thresholdstate_test.go blockchain: Use hash values in structs. 2017-02-03 11:36:33 -06:00
timesorter.go blockchain: Use int64 timestamps in block nodes. 2017-01-31 17:51:29 -06:00
timesorter_test.go blockchain: Use int64 timestamps in block nodes. 2017-01-31 17:51:29 -06:00
utxoviewpoint.go mempool: Add basic test harness infrastructure. 2016-08-24 10:04:40 -05:00
validate.go Fix a ton of typos accumulated over time 2017-05-30 16:59:51 +02:00
validate_test.go wire: Make NewMsgTx accept the tx version. 2016-10-27 14:09:29 -05:00
versionbits.go blockchain: Refactor main block index logic. 2017-02-01 13:14:41 -06:00

blockchain

Build Status ISC License GoDoc

Package blockchain implements bitcoin block handling and chain selection rules. The test coverage is currently only around 60%, but will be increasing over time. See test_coverage.txt for the gocov coverage report. Alternatively, if you are running a POSIX OS, you can run the cov_report.sh script for a real-time report. Package blockchain is licensed under the liberal ISC license.

There is an associated blog post about the release of this package here.

This package has intentionally been designed so it can be used as a standalone package for any projects needing to handle processing of blocks into the bitcoin block chain.

Installation and Updating

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

Bitcoin Chain Processing Overview

Before a block is allowed into the block chain, it must go through an intensive series of validation rules. The following list serves as a general outline of those rules to provide some intuition into what is going on under the hood, but is by no means exhaustive:

  • Reject duplicate blocks
  • Perform a series of sanity checks on the block and its transactions such as verifying proof of work, timestamps, number and character of transactions, transaction amounts, script complexity, and merkle root calculations
  • Compare the block against predetermined checkpoints for expected timestamps and difficulty based on elapsed time since the checkpoint
  • Save the most recent orphan blocks for a limited time in case their parent blocks become available
  • Stop processing if the block is an orphan as the rest of the processing depends on the block's position within the block chain
  • Perform a series of more thorough checks that depend on the block's position within the block chain such as verifying block difficulties adhere to difficulty retarget rules, timestamps are after the median of the last several blocks, all transactions are finalized, checkpoint blocks match, and block versions are in line with the previous blocks
  • Determine how the block fits into the chain and perform different actions accordingly in order to ensure any side chains which have higher difficulty than the main chain become the new main chain
  • When a block is being connected to the main chain (either through reorganization of a side chain to the main chain or just extending the main chain), perform further checks on the block's transactions such as verifying transaction duplicates, script complexity for the combination of connected scripts, coinbase maturity, double spends, and connected transaction values
  • Run the transaction scripts to verify the spender is allowed to spend the coins
  • Insert the block into the block database

Examples

  • ProcessBlock Example
    Demonstrates how to create a new chain instance and use ProcessBlock to attempt to attempt add a block to the chain. This example intentionally attempts to insert a duplicate genesis block to illustrate how an invalid block is handled.

  • CompactToBig Example
    Demonstrates how to convert the compact "bits" in a block header which represent the target difficulty to a big integer and display it using the typical hex notation.

  • BigToCompact Example
    Demonstrates how to convert how to convert a target difficulty into the compact "bits" in a block header which represent that target difficulty.

GPG Verification Key

All official release tags are signed by Conformal so users can ensure the code has not been tampered with and is coming from the btcsuite developers. To verify the signature perform the following:

  • Download the public key from the Conformal website at https://opensource.conformal.com/GIT-GPG-KEY-conformal.txt

  • Import the public key into your GPG keyring:

    gpg --import GIT-GPG-KEY-conformal.txt
    
  • Verify the release tag with the following command where TAG_NAME is a placeholder for the specific tag:

    git tag -v TAG_NAME
    

License

Package blockchain is licensed under the copyfree ISC License.