fix(proxy): close miners during shutdown

Co-Authored-By: Virgil <virgil@lethean.io>

state_impl.go

@@ -244,6 +244,7 @@ func (p *Proxy) Stop() {
 		for _, server := range p.servers {
 			server.Stop()
 		}
+		p.closeAllMiners()
 		if p.watcher != nil {
 			p.watcher.Stop()
 		}
@@ -262,6 +263,23 @@ func (p *Proxy) Stop() {
 	})
 }
 
+func (p *Proxy) closeAllMiners() {
+	if p == nil {
+		return
+	}
+	p.minersMu.RLock()
+	miners := make([]*Miner, 0, len(p.miners))
+	for _, miner := range p.miners {
+		miners = append(miners, miner)
+	}
+	p.minersMu.RUnlock()
+	for _, miner := range miners {
+		if miner != nil {
+			miner.Close()
+		}
+	}
+}
+
 // Reload swaps the live configuration and updates dependent state.
 func (p *Proxy) Reload(cfg *Config) {
 	if p == nil || cfg == nil {

state_stop_test.go

@@ -0,0 +1,62 @@
+package proxy
+
+import (
+	"net"
+	"testing"
+	"time"
+)
+
+func TestProxy_Stop_Good(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+
+	miner := NewMiner(clientConn, 3333, nil)
+	proxyInstance := &Proxy{
+		done:   make(chan struct{}),
+		miners: map[int64]*Miner{miner.ID(): miner},
+	}
+
+	done := make(chan error, 1)
+	go func() {
+		buf := make([]byte, 1)
+		_, err := serverConn.Read(buf)
+		done <- err
+	}()
+
+	time.Sleep(10 * time.Millisecond)
+	proxyInstance.Stop()
+
+	select {
+	case err := <-done:
+		if err == nil {
+			t.Fatalf("expected miner connection to close during Stop")
+		}
+	case <-time.After(time.Second):
+		t.Fatalf("expected miner connection to close during Stop")
+	}
+}
+
+func TestProxy_Stop_Bad(t *testing.T) {
+	var proxyInstance *Proxy
+
+	proxyInstance.Stop()
+}
+
+func TestProxy_Stop_Ugly(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	defer serverConn.Close()
+
+	miner := NewMiner(clientConn, 3333, nil)
+	proxyInstance := &Proxy{
+		done:   make(chan struct{}),
+		miners: map[int64]*Miner{miner.ID(): miner},
+	}
+
+	proxyInstance.Stop()
+	proxyInstance.Stop()
+
+	buf := make([]byte, 1)
+	if _, err := serverConn.Read(buf); err == nil {
+		t.Fatalf("expected closed connection after repeated Stop calls")
+	}
+}