Basic integration with the electrum server electrs

[dagurval]

This is a MVP for integrating electrum server with Bitcoin Unlimited.

To enable the server, you need to run make electrs and add electrum=1 to bitcoin.conf. Adding debug=electrum will enable more useful logging.

[dagurval]

A way to test this with Electron Cash is by running

./electron-cash -v --oneserver --server=127.0.0.1:60001:t --testnet

and creating a wallet with the tpub key tpubD6NzVbkrYhZ4YRDtddy5nLmvdH7Qn6oR7euDpjqnZdniaJDTbaL17Gq86bsVNhKMkYwGvSvhamz5QkouzGJ4e2rkyHWbF5mHGX5Up377zBM

Electron Cash also has added a nice feature to rebuild the wallet history Wallet -> Rebuild history.

Beware of this bug in electron cash Electron-Cash/Electron-Cash#1222

[sickpig]

@dagurval

What about adding some words about what elecrtrs is?

[gandrewstone]

I did an out-of-source-tree build but the electrs binary still goes to src/electrs. To replicate this, from your base git checkout dir:
./autogen.sh
mkdir debug
cd debug
../configure [optional: --enable-debug --enable-shared]
make V=1
make electrs

[gandrewstone]

ss << " " << a;

Or you get an executable named "electrs-vvvv", and an extra space at the end I presume, (in the log only).

[dagurval]

Fixed

[gandrewstone]

I get:

2019-04-03 19:47:16 Electrum: spawning /fast/bitcoin/buelectrum/src/electrs -vvvv --daemon-rpc-addr=localhost:18332 --daemon-dir=/home/stone/.bitcoin/testnet3 --jsonrpc-import --db-dir=/home/stone/.bitcoin/testnet3/electrs --network=testnet --monitoring-addr=127.0.0.1:4224 --cookie=thezerg:34983429q980dkdkdsakd --txid-limit=500
2019-04-03 19:47:16 Electrum: stderr log thread started.
2019-04-03 19:47:16 Electrum: stdout log thread started.
2019-04-03 19:47:16 Electrum: server exited with exit code: 32
2019-04-03 19:47:16 Error: Unable to start RPC services. See debug log for details.

BUT when I run the spawn line directly on the command line I get:

/fast/bitcoin/buelectrum/src/electrs -vvvv --daemon-rpc-addr=localhost:18332 --daemon-dir=/home/stone/.bitcoin/testnet3 --jsonrpc-import --db-dir=/home/stone/.bitcoin/testnet3/electrs --network=testnet --monitoring-addr=127.0.0.1:4224 --cookie=thezerg:34983429q980dkdkdsakd --txid-limit=500
Config { log: StdErrLog { verbosity: Trace, quiet: false, timestamp: Off, modules: [], writer: "stderr", color_choice: Auto }, network_type: testnet, db_path: "/home/stone/.bitcoin/testnet3/electrs/testnet", daemon_dir: "/home/stone/.bitcoin/testnet3/testnet3", daemon_rpc_addr: V4(127.0.0.1:18332), cookie: Some("thezerg:34983429q980dkdkdsakd"), electrum_rpc_addr: V4(127.0.0.1:60001), monitoring_addr: V4(127.0.0.1:4224), jsonrpc_import: true, index_batch_size: 100, bulk_index_threads: 12, tx_cache_size: 10000, txid_limit: 500, server_banner: "Welcome to electrs (Electrum Rust Server)!" }
DEBUG - Server listening on 127.0.0.1:4224
WARN - failed to connect daemon at 127.0.0.1:18332: Connection refused (os error 111)
DEBUG - Running accept thread
WARN - failed to connect daemon at 127.0.0.1:18332: Connection refused (os error 111)
WARN - failed to connect daemon at 127.0.0.1:18332: Connection refused (os error 111)
.
.
.

so it looks like its working from the command line.

[dagurval]

so it looks like its working from the command line.

Weird. Not sure how to reproduce that. Does the qa test run? ./qa/rpc-tests/electrum_basics.py

[dagurval]

rebased on top of #1646 and #1645

[gandrewstone]

PWD is not necessarily the out-of-source dir, use top_builddir. And if ${PWD}/src/electrs does not exist, there's no rule to make it. Instead use a phony target that points to the real target like this:

.PHONY: electrs

electrs: $(top_builddir)/src/electrs

$(top_builddir)/src/electrs:
	$(top_srcdir)/contrib/electrs/build_electrs.py --dst=$(top_builddir)/src

[dagurval]

fixed in 8100042

[dagurval]

Rebased again on top of #1645 and added gitian build support on Linux