From 6b218099f1dc05f66415a995a32777552b540d2f Mon Sep 17 00:00:00 2001
From: Joshua Sing <joshua@bloq.com>
Date: Thu, 22 Aug 2024 04:37:25 +1000
Subject: [PATCH] bfgd, electrumx: make initial and max conns configurable
 (#206)

---
 cmd/bfgd/bfgd.go                 | 12 ++++++++++++
 cmd/extool/extool.go             |  2 +-
 docker/bfgd/Dockerfile           | 22 +++++++++++++---------
 hemi/electrumx/conn_pool_test.go |  5 +++++
 hemi/electrumx/electrumx.go      | 10 ++--------
 service/bfg/bfg.go               |  6 +++++-
 6 files changed, 38 insertions(+), 19 deletions(-)

diff --git a/cmd/bfgd/bfgd.go b/cmd/bfgd/bfgd.go
index 9c33073b..d743f60b 100644
--- a/cmd/bfgd/bfgd.go
+++ b/cmd/bfgd/bfgd.go
@@ -37,6 +37,18 @@ var (
 			Help:         "electrumx endpoint",
 			Print:        config.PrintAll,
 		},
+		"BFG_EXBTC_INITIAL_CONNECTIONS": config.Config{
+			Value:        &cfg.EXBTCInitialConns,
+			DefaultValue: 5,
+			Help:         "electrumx initial connections",
+			Print:        config.PrintAll,
+		},
+		"BFG_EXBTC_MAX_CONNECTIONS": config.Config{
+			Value:        &cfg.EXBTCMaxConns,
+			DefaultValue: 100,
+			Help:         "electrumx max connections",
+			Print:        config.PrintAll,
+		},
 		"BFG_PUBLIC_KEY_AUTH": config.Config{
 			Value:        &cfg.PublicKeyAuth,
 			DefaultValue: false,
diff --git a/cmd/extool/extool.go b/cmd/extool/extool.go
index 07676875..6572a09a 100644
--- a/cmd/extool/extool.go
+++ b/cmd/extool/extool.go
@@ -37,7 +37,7 @@ func main() {
 		log.Fatal("No address specified")
 	}
 
-	c, err := electrumx.NewClient(address)
+	c, err := electrumx.NewClient(address, 1, 1)
 	if err != nil {
 		log.Fatalf("Failed to create electrumx client: %v", err)
 	}
diff --git a/docker/bfgd/Dockerfile b/docker/bfgd/Dockerfile
index aff38699..6097922f 100644
--- a/docker/bfgd/Dockerfile
+++ b/docker/bfgd/Dockerfile
@@ -55,15 +55,19 @@ COPY --from=builder /usr/share/zoneinfo /usr/share/zoneinfo
 COPY --from=builder /build/bin/bfgd /usr/local/bin/bfgd
 
 # Environment variables
-ENV BFG_EXBTC_ADDRESS=
-ENV BFG_PUBLIC_KEY_AUTH=
-ENV BFG_BTC_START_HEIGHT=
-ENV BFG_LOG_LEVEL=
-ENV BFG_POSTGRES_URI=
-ENV BFG_PUBLIC_ADDRESS=
-ENV BFG_PRIVATE_ADDRESS=
-ENV BFG_PROMETHEUS_ADDRESS=
-ENV BFG_PPROF_ADDRESS=
+ENV BFG_EXBTC_ADDRESS=""
+ENV BFG_EXBTC_INITIAL_CONNECTIONS=""
+ENV BFG_EXBTC_MAX_CONNECTIONS=""
+ENV BFG_PUBLIC_KEY_AUTH=""
+ENV BFG_BTC_START_HEIGHT=""
+ENV BFG_LOG_LEVEL=""
+ENV BFG_POSTGRES_URI=""
+ENV BFG_PUBLIC_ADDRESS=""
+ENV BFG_PRIVATE_ADDRESS=""
+ENV BFG_PROMETHEUS_ADDRESS=""
+ENV BFG_PPROF_ADDRESS=""
+ENV BFG_REQUEST_LIMIT=""
+ENV BFG_REQUEST_TIMEOUT=""
 
 USER bfgd:bfgd
 WORKDIR /etc/bfgd/
diff --git a/hemi/electrumx/conn_pool_test.go b/hemi/electrumx/conn_pool_test.go
index b093d446..3e72245e 100644
--- a/hemi/electrumx/conn_pool_test.go
+++ b/hemi/electrumx/conn_pool_test.go
@@ -10,6 +10,11 @@ import (
 	"time"
 )
 
+const (
+	clientInitialConnections = 2
+	clientMaximumConnections = 5
+)
+
 func TestConnPool(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 	defer cancel()
diff --git a/hemi/electrumx/electrumx.go b/hemi/electrumx/electrumx.go
index 2305371d..f2b32470 100644
--- a/hemi/electrumx/electrumx.go
+++ b/hemi/electrumx/electrumx.go
@@ -124,19 +124,13 @@ type Client struct {
 
 var log = loggo.GetLogger("electrumx")
 
-const (
-	clientInitialConnections = 2
-	clientMaximumConnections = 5
-)
-
 // NewClient returns an initialised electrumx client.
-func NewClient(address string) (*Client, error) {
+func NewClient(address string, initialConns, maxConns int) (*Client, error) {
 	c := &Client{}
 
 	// The address may be empty during tests, ignore empty addresses.
 	if address != "" {
-		pool, err := newConnPool("tcp", address,
-			clientInitialConnections, clientMaximumConnections)
+		pool, err := newConnPool("tcp", address, initialConns, maxConns)
 		if err != nil {
 			return nil, fmt.Errorf("new connection pool: %w", err)
 		}
diff --git a/service/bfg/bfg.go b/service/bfg/bfg.go
index 7b679c95..db6837eb 100644
--- a/service/bfg/bfg.go
+++ b/service/bfg/bfg.go
@@ -63,6 +63,8 @@ func init() {
 func NewDefaultConfig() *Config {
 	return &Config{
 		EXBTCAddress:         "localhost:18001",
+		EXBTCInitialConns:    5,
+		EXBTCMaxConns:        100,
 		PrivateListenAddress: ":8080",
 		PublicListenAddress:  ":8383",
 		RequestLimit:         bfgapi.DefaultRequestLimit,
@@ -86,6 +88,8 @@ type btcClient interface {
 type Config struct {
 	BTCStartHeight          uint64
 	EXBTCAddress            string
+	EXBTCInitialConns       int
+	EXBTCMaxConns           int
 	PrivateListenAddress    string
 	PublicListenAddress     string
 	LogLevel                string
@@ -213,7 +217,7 @@ func NewServer(cfg *Config) (*Server, error) {
 	}
 
 	var err error
-	s.btcClient, err = electrumx.NewClient(cfg.EXBTCAddress)
+	s.btcClient, err = electrumx.NewClient(cfg.EXBTCAddress, cfg.EXBTCInitialConns, cfg.EXBTCMaxConns)
 	if err != nil {
 		return nil, fmt.Errorf("create electrumx client: %w", err)
 	}