network: make minpeers configurable

Without it node in privnet tries to reconnect to four existing nodes
indefinitely for no good reason.

config/config.go

@@ -73,6 +73,7 @@ type (
 		DialTimeout       time.Duration            `yaml:"DialTimeout"`
 		ProtoTickInterval time.Duration            `yaml:"ProtoTickInterval"`
 		MaxPeers          int                      `yaml:"MaxPeers"`
+		MinPeers          int                      `yaml:"MinPeers"`
 		Monitoring        metrics.PrometheusConfig `yaml:"Monitoring"`
 	}
 

config/protocol.mainnet.yml

@@ -48,6 +48,7 @@ ApplicationConfiguration:
   DialTimeout: 3
   ProtoTickInterval: 2
   MaxPeers: 50
+  MinPeers: 5
   Monitoring:
     Enabled: true
     Port: 2112

config/protocol.privnet.docker.four.yml

@@ -36,6 +36,7 @@ ApplicationConfiguration:
   DialTimeout: 3
   ProtoTickInterval: 2
   MaxPeers: 50
+  MinPeers: 3
   Monitoring:
     Enabled: true
     Port: 2112

config/protocol.privnet.docker.one.yml

@@ -33,6 +33,7 @@ ApplicationConfiguration:
   DialTimeout: 3
   ProtoTickInterval: 2
   MaxPeers: 50
+  MinPeers: 3
   Monitoring:
     Enabled: true
     Port: 2112

config/protocol.privnet.docker.three.yml

@@ -33,6 +33,7 @@ ApplicationConfiguration:
   DialTimeout: 3
   ProtoTickInterval: 2
   MaxPeers: 50
+  MinPeers: 3
   Monitoring:
     Enabled: true
     Port: 2112

config/protocol.privnet.docker.two.yml

@@ -33,6 +33,7 @@ ApplicationConfiguration:
   DialTimeout: 3
   ProtoTickInterval: 2
   MaxPeers: 50
+  MinPeers: 3
   Monitoring:
     Enabled: true
     Port: 2112

config/protocol.privnet.yml

@@ -39,6 +39,7 @@ ApplicationConfiguration:
   DialTimeout: 3
   ProtoTickInterval: 2
   MaxPeers: 50
+  MinPeers: 3
   Monitoring:
     Enabled: true
     Port: 2112

config/protocol.testnet.yml

@@ -48,6 +48,7 @@ ApplicationConfiguration:
   DialTimeout: 3
   ProtoTickInterval: 2
   MaxPeers: 50
+  MinPeers: 5
   Monitoring:
     Enabled: true
     Port: 2112

config/protocol.unit_testnet.yml

@@ -38,6 +38,7 @@ ApplicationConfiguration:
   DialTimeout: 3
   ProtoTickInterval: 2
   MaxPeers: 50
+  MinPeers: 1
   Monitoring:
     Enabled: false #since it's not useful for unit tests.
     Port: 2112

pkg/network/server.go

@@ -18,7 +18,6 @@ import (
 
 const (
 	// peer numbers are arbitrary at the moment.
-	minPeers       = 5
 	maxPeers       = 20
 	maxBlockBatch  = 200
 	maxAddrsToSend = 200
@@ -71,7 +70,7 @@ func NewServer(config ServerConfig, chain core.Blockchainer) *Server {
 		bQueue:       newBlockQueue(maxBlockBatch, chain),
 		id:           rand.Uint32(),
 		quit:         make(chan struct{}),
-		addrReq:      make(chan *Message, minPeers),
+		addrReq:      make(chan *Message, config.MinPeers),
 		register:     make(chan Peer),
 		unregister:   make(chan peerDrop),
 		peers:        make(map[Peer]bool),
@@ -129,7 +128,7 @@ func (s *Server) BadPeers() []string {
 func (s *Server) run() {
 	for {
 		c := s.PeerCount()
-		if c < minPeers {
+		if c < s.ServerConfig.MinPeers {
 			s.discovery.RequestRemote(maxPeers - c)
 		}
 		if s.discovery.PoolCount() < minPoolCount {

pkg/network/server_config.go

@@ -10,6 +10,11 @@ import (
 type (
 	// ServerConfig holds the server configuration.
 	ServerConfig struct {
+		// MinPeers is the minimum number of peers for normal operation,
+		// when the node has less than this number of peers it tries to
+		// connect with some new ones.
+		MinPeers int
+
 		// MaxPeers it the maximum numbers of peers that can
 		// be connected to the server.
 		MaxPeers int
@@ -59,5 +64,6 @@ func NewServerConfig(cfg config.Config) ServerConfig {
 		DialTimeout:       appConfig.DialTimeout * time.Second,
 		ProtoTickInterval: appConfig.ProtoTickInterval * time.Second,
 		MaxPeers:          appConfig.MaxPeers,
+		MinPeers:          appConfig.MinPeers,
 	}
 }