dcrd/blockchain
Dave Collins 69f8579231
multi: No winning ticket ntfns for big reorg depth.
This modifies the logic which sends winning ticket notifications to RPC
clients to consider the reorganization depth and refuse to send the
notifications for blocks on side chains that would ultimately result in
a reorg of 6 or more blocks.

Also, the code used to send the notifications was needlessly repeated in
multiple places since any blocks accepted via ProcessBlock also result
in an accepted notification and therefore the RPC notification only
needs to be sent from there.
2018-05-29 11:16:09 -05:00
..
chaingen blockchain: utilize CalcNextReqStakeDifficulty in fullblocktests. 2018-05-08 15:28:28 -05:00
fullblocktests fullblocktests: add additional premine and malformed tests. 2018-05-09 16:40:24 -05:00
indexers multi: Replace btclog with slog. 2018-05-23 14:22:10 -05:00
internal multi: Replace btclog with slog. 2018-05-23 14:22:10 -05:00
stake multi: Replace btclog with slog. 2018-05-23 14:22:10 -05:00
testdata blockchain: Use chaingen for forced reorg tests. 2018-02-23 21:01:02 -06:00
accept.go multi: No winning ticket ntfns for big reorg depth. 2018-05-29 11:16:09 -05:00
agendas_test.go blockchain: Switch to FindSpentTicketsInBlock. 2018-01-28 21:21:10 -06:00
bench_test.go blockchain: Consolidate tests into the main package. 2018-02-25 19:01:57 -06:00
blockindex_test.go blockchain: Add tests for chain tip tracking. 2018-02-28 10:55:51 -06:00
blockindex.go blockchain: Simplify chain tip tracking. 2018-02-27 21:26:21 -06:00
blocklocator.go blockchain: Refactor main block index logic. 2018-01-30 13:21:57 -06:00
chain_test.go multi: Return fork len from ProcessBlock. 2018-05-27 20:20:43 -05:00
chain.go multi: Return fork len from ProcessBlock. 2018-05-27 20:20:43 -05:00
chainio_test.go blockchain: Refactor block idx entry serialization. 2018-02-23 14:36:08 -06:00
chainio.go blockchain: Cache tip and parent at init. 2018-03-01 12:05:18 -06:00
chainquery.go multi: Implement getchaintips JSON-RPC. 2018-03-01 12:29:36 -06:00
checkpoints.go Merge remaining dcrutil code into a dcrd package. 2017-10-11 22:06:36 -04:00
common_test.go blockchain: Add tests for chain tip tracking. 2018-02-28 10:55:51 -06:00
compress_test.go blockchain: Rework to use new db interface. 2016-08-18 15:42:18 -04:00
compress.go blockchain: use secp256k1 functions directly. 2018-05-23 01:34:50 -05:00
difficulty_test.go blockchain: Support testnet stake diff estimation. 2018-03-05 12:07:58 -06:00
difficulty.go blockchain: Support testnet stake diff estimation. 2018-03-05 12:07:58 -06:00
doc.go multi: Properly capitalize Decred. 2018-03-01 17:41:35 -06:00
error_test.go blockchain: rename ErrRegTxSpendStakeOut to ErrRegTxCreateStakeOut. 2018-05-07 18:19:32 -05:00
error.go blockchain: rename ErrRegTxSpendStakeOut to ErrRegTxCreateStakeOut. 2018-05-07 18:19:32 -05:00
example_test.go multi: Return fork len from ProcessBlock. 2018-05-27 20:20:43 -05:00
fullblocks_test.go multi: Return fork len from ProcessBlock. 2018-05-27 20:20:43 -05:00
fullblocksstakeversion_test.go multi: Return fork len from ProcessBlock. 2018-05-27 20:20:43 -05:00
go.mod multi: Define vgo modules. 2018-05-25 15:38:16 -05:00
go.modverify multi: Define vgo modules. 2018-05-25 15:38:16 -05:00
log.go multi: Replace btclog with slog. 2018-05-23 14:22:10 -05:00
mediantime_test.go blockchain: Consolidate tests into the main package. 2018-02-25 19:01:57 -06:00
mediantime.go Initial Decred Commit. 2016-02-07 14:00:12 -05:00
merkle_test.go blockchain: Consolidate tests into the main package. 2018-02-25 19:01:57 -06:00
merkle.go multi: Properly capitalize Decred. 2018-03-01 17:41:35 -06:00
notifications.go multi: No winning ticket ntfns for big reorg depth. 2018-05-29 11:16:09 -05:00
process.go multi: Return fork len from ProcessBlock. 2018-05-27 20:20:43 -05:00
prune.go chain: Remove memory block node pruning. 2017-09-18 13:43:48 -05:00
README.md Fix typo in blockchain typo 2018-05-03 14:37:37 -04:00
scriptval.go blockchain: Combine ErrDoubleSpend & ErrMissingTx. 2018-02-21 14:01:05 -06:00
sequencelock_test.go blockchain: Refactor main block index logic. 2018-01-30 13:21:57 -06:00
sequencelock.go blockchain: Combine ErrDoubleSpend & ErrMissingTx. 2018-02-21 14:01:05 -06:00
stakeext.go blockchain: Refactor main block index logic. 2018-01-30 13:21:57 -06:00
stakenode.go blockchain: Calculate the lottery IV on demand. 2018-02-21 16:44:54 -06:00
stakeversion_test.go blockchain: Consolidate tests into the main package. 2018-02-25 19:01:57 -06:00
stakeversion.go blockchain: Simplify voter version calculation. 2018-02-26 13:40:47 -06:00
subsidy_test.go blockchain: Consolidate tests into the main package. 2018-02-25 19:01:57 -06:00
subsidy.go blockchain: Improve readability of parent approval. 2018-02-02 18:33:41 -06:00
thresholdstate_test.go multi: Return fork len from ProcessBlock. 2018-05-27 20:20:43 -05:00
thresholdstate.go multi: fix misspell linter warnings 2018-02-18 12:26:52 -06:00
timesorter_test.go blockchain: Consolidate tests into the main package. 2018-02-25 19:01:57 -06:00
timesorter.go blockchain: Don't store full header in block node. 2018-01-29 11:35:06 -06:00
upgrade.go blockchain: Refactor block idx entry serialization. 2018-02-23 14:36:08 -06:00
utxoviewpoint.go blockchain: Only fetch inputs once in connect txns. 2018-03-21 20:13:37 -05:00
validate_test.go multi: Return fork len from ProcessBlock. 2018-05-27 20:20:43 -05:00
validate.go blockchain: Validate tx expiry in block context. 2018-05-09 18:54:57 -05:00
votebits_test.go blockchain: Remove unused threshold serialization. 2018-02-27 00:55:13 -06:00
votebits.go blockchain: Don't store full header in block node. 2018-01-29 11:35:06 -06:00

blockchain

Build Status ISC License GoDoc

Package blockchain implements Decred 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 decred block chain.

Installation and Updating

$ go get -u github.com/decred/dcrd/blockchain

Decred 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 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.

License

Package blockchain is licensed under the copyfree ISC License.