68c24b5701
Review follow-ups to 73a93f1. Bound in-flight calls. rpcclient's single sendPostHandler goroutine imposed an accidental ceiling of one concurrent RPC; removing it without putting anything in its place left no bound at all. grpc-go supplies none either -- this server sets no MaxConcurrentStreams, so the default is math.MaxUint32 -- and dragonxd answers RPC with 8 worker threads behind a 4096-deep queue, shared on the pool node with getblocktemplate. Overload would therefore surface as mining latency rather than as an error we could back off on. MaxConnsPerHost blocks the caller at the limit instead of dialling more, which is the backpressure wanted; MaxIdleConnsPerHost alone would only cap reuse and let us exceed the limit while churning connections. Default 8, matching the node's DEFAULT_HTTP_THREADS, tunable with -rpc-max-concurrent. Even 8 removes all of the head-of-line blocking this work set out to fix. IdleConnTimeout 90s -> 20s. dragonxd closes idle connections at 30s (DEFAULT_HTTP_SERVER_TIMEOUT, applied via evhttp_set_timeout and not overridden in DRAGONX.conf). At 90s we were always the second to close, so a request could be written into a connection the server had already sent a FIN for, and Go will not retry a POST once bytes are on the wire. Closing first removes the race. Reject a negative -rpc-timeout, which silently meant "unbounded", the same as the documented 0. The check has to run after flag.Parse(); it was initially placed before it and never fired. Also correct the coinsupply note: hush_coinsupply walks the block index back to genesis, loading each block from disk and memoising newcoins and zfunds into the CBlockIndex, so the first call pays for the whole chain and later ones are nearly free. It is not a UTXO-set scan, as the earlier comment claimed. The measured 48s/3s figures are unchanged. Verified: five concurrent GetLightdInfo calls all return grpc-status 0 with no errors, 46 blocks ingested, and the daemon holds 2 sockets to the node rather than one per request; a negative timeout exits 1. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01FU87LdsJZiZkfq1eXubpeo
Overview
DragonX Lightwalletd is a fork of Hush lightwalletd which is itself a fork of lightwalletd originally from Zcash (ZEC).
It is a backend service that provides a bandwidth-efficient interface to the DragonX blockchain for light wallet clients.
Features
- Support for DragonX (standalone chain with
dragonxd) - Support for transparent addresses
- Several RPC calls for light clients
- Lots of perf improvements
- In-memory cache for Compact Blocks (replaces SQLite)
- Tx lookups delegated to dragonxd
- No separate ingestor needed
Running your own DragonX lightwalletd
0. First, install Go
You will need Go >= 1.13 which you can download from the official download page or install via your OS package manager.
This installation document shows how to do it on various OS's.
If you're using Ubuntu or Debian, try:
$ sudo apt install golang
1. Run a DragonX node.
Install the DragonX daemon (dragonxd) and CLI (dragonx-cli).
Next, ensure your DRAGONX.conf file (at ~/.hush/DRAGONX/DRAGONX.conf) has something like the following:
rpcuser=user-CHANGETHIS
rpcpassword=pass-CHANGETHIS
rpcport=21769
server=1
txindex=1
rpcworkqueue=256
rpcallowip=127.0.0.1
rpcbind=127.0.0.1
Then start dragonxd. You might need to run with -reindex the first time if you are enabling the txindex option for the first time. The reindex might take a while.
2. Compile lightwalletd
Run the build script.
make build
3. Get a TLS certificate and run the Lightwalletd frontend
First, get a TLS certificate:
On Ubuntu Linux, I SUGGEST YOU DO NOT USE SNAPD and just sudo apt install certbot and then start on Step 7 of these instructions by the EFF
Next you decide how you want to setup lightwalletd - with (Option A) or without NGINX (Option B).
Option A: "Let's Encrypt" certificate using NGINX as a reverse proxy
If you running a public-facing server, the easiest way to obtain a certificate is to use a NGINX reverse proxy and get a Let's Encrypt certificate.
Create a new section for the NGINX reverse proxy:
server {
listen 443 ssl http2;
listen [::]:443 ssl http2;
server_name your_host.net;
ssl_certificate /etc/letsencrypt/live/your_host.net/fullchain.pem; # managed by Certbot
ssl_certificate_key /etc/letsencrypt/live/your_host.net/privkey.pem; # managed by Certbot
include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot
location / {
# Replace localhost:9069 with the address and port of your gRPC server if using a custom port
grpc_pass grpc://your_host.net:9069;
}
}
Then run the lightwalletd frontend with the following (Note: we use the "-no-tls" option as we are using NGINX as a reverse proxy and letting it handle the TLS authentication for us instead):
./lightwalletd -bind-addr your_host.net:9069 -conf-file ~/.hush/DRAGONX/DRAGONX.conf -no-tls
Option B: "Let's Encrypt" certificate just using lightwalletd without NGINX
The other option is to configure lightwalletd to handle its own TLS authentication. Once you have a certificate that you want to use (from a certificate authority), pass the certificate to the frontend as follows:
./lightwalletd -bind-addr 127.0.0.1:9069 -conf-file ~/.hush/DRAGONX/DRAGONX.conf -tls-cert /etc/letsencrypt/live/YOURWEBSITE/fullchain.pem -tls-key /etc/letsencrypt/live/YOURWEBSITE/privkey.pem
4. Point a light wallet client to this server
You should start seeing the frontend ingest and cache the DragonX blocks after ~15 seconds.
Lightwalletd Command-line Options
These are the current different command line options for lightwalletd:
| CLI option | Default | What it does |
|---|---|---|
| -bind-addr | 127.0.0.1:9069 | address and port to listen on |
| -tls-cert | blank | the path to a TLS certificate |
| -tls-key | blank | the path to a TLS key file |
| -no-tls | false | Disable TLS, serve un-encrypted traffic |
| -log-file | blank | log file to write to |
| -log-level | logrus.InfoLevel | log level 1 thru 7 (something from logrus) |
| -conf-file | blank | conf file to pull RPC creds from |
| -cache-size | 40000 | number of blocks to hold in the cache |
Support
For support or other questions, join us on Telegram or join Telegram Support.
License
GPLv3 or later
Copyright
2016-2022 The Hush Developers 2024-2026 The DragonX Developers