This PR slightly modifies the dumptxoutset RPC to allow writing the UTXO set dump into a named pipe, so that the output data can be consumed by another process, see #31373. Taking use of this with the utxo-to-sqlite.py tool (introduced in #27432), creating an UTXO set in SQLite3 format is possible on the fly and becomes a one-liner with a newly introduced script dump_to_sqlite.sh. E.g. for signet:
0$ ./contrib/utxo-tools/dump_to_sqlite.sh "./build/src/bitcoin-cli -signet" ~/utxos.sqlite3
1UTXO Snapshot for Signet at block hash 000000ddc3b251483cf1ebb23e2750ba..., contains 5705634 coins
21048576 coins converted [18.38%], 4.474s passed since start
32097152 coins converted [36.76%], 8.793s passed since start
43145728 coins converted [55.13%], 13.146s passed since start
54194304 coins converted [73.51%], 17.478s passed since start
65242880 coins converted [91.89%], 21.832s passed since start
7{
8 "coins_written": 5705634,
9 "base_hash": "000000ddc3b251483cf1ebb23e2750ba2490701d0c547241b247a9beb85498d0",
10 "base_height": 227678,
11 "path": "/tmp/tmp.MFHEVqetv0/utxos.fifo",
12 "txoutset_hash": "f29e524c999487cbd0cfca5201dce67c2c5e5c5eb115c63ad48c2239f23eea4c",
13 "nchaintx": 8272649
14}
15TOTAL: 5705634 coins written to /home/thestack/utxos.sqlite3, snapshot height is 227678.
Note that the dumptxoutset RPC calculates an UTXO set hash as a first step before any data is emitted, so especially on mainnet it takes quite a while until the conversion starts and something is happening visibly.
The new script is quite minimal and PoC-y at this point, there are some potential improvement ideas:
- better error handling (e.g. detect if bitcoin-cli exists, clean up tmpdir if bitcoin-cli execution fails etc.)
- allow to pass through the rollback option (now we always dump at the current height, i.e. “latest” parameter)
