Wait for the power lock when stopping or killing a booting server

Fixes pterodactyl/panel#5712

router/router_server.go

@@ -86,7 +86,10 @@ func postServerPower(c *gin.Context) {
 	// we can immediately return a response from the server. Some of these actions
 	// can take quite some time, especially stopping or restarting.
 	go func(s *server.Server) {
-		if data.WaitSeconds < 0 || data.WaitSeconds > 300 {
+		// The response has already been sent, so an action that cannot get the power lock
+		// right away would be dropped without the caller knowing. Wait for the lock by default
+		// so that a stop or kill sent while the server is booting runs once the boot finishes.
+		if data.WaitSeconds <= 0 || data.WaitSeconds > 300 {
 			data.WaitSeconds = 30
 		}
 		if err := s.HandlePowerAction(data.Action, data.WaitSeconds); err != nil {

router/router_server_power_test.go

@@ -0,0 +1,68 @@
+package router
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/apex/log"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+
+	"github.com/pterodactyl/wings/environment"
+	wserver "github.com/pterodactyl/wings/server"
+)
+
+// powerTestEnvironment reports each stop on stops and holds it until release is closed.
+type powerTestEnvironment struct {
+	environment.ProcessEnvironment
+	stops   chan struct{}
+	release chan struct{}
+}
+
+func (e *powerTestEnvironment) WaitForStop(context.Context, time.Duration, bool) error {
+	e.stops <- struct{}{}
+	<-e.release
+	return nil
+}
+
+// A stop sent without wait_seconds while another power action holds the lock runs
+// once the lock is released, instead of being dropped after the 202 response.
+func TestStopWithoutWaitSecondsWaitsForPowerLock(t *testing.T) {
+	s, err := wserver.New(nil)
+	require.NoError(t, err)
+	t.Cleanup(s.CtxCancel)
+	env := &powerTestEnvironment{stops: make(chan struct{}, 2), release: make(chan struct{})}
+	s.Environment = env
+
+	go func() { _ = s.HandlePowerAction(wserver.PowerActionStop) }()
+	<-env.stops
+
+	gin.SetMode(gin.TestMode)
+	w := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(w)
+	c.Request = httptest.NewRequest(http.MethodPost, "/api/servers/test/power", strings.NewReader(`{"action":"stop"}`))
+	c.Request.Header.Set("Content-Type", "application/json")
+	c.Set("server", s)
+	c.Set("logger", log.WithField("test", t.Name()))
+
+	postServerPower(c)
+	require.Equal(t, http.StatusAccepted, c.Writer.Status())
+
+	select {
+	case <-env.stops:
+		t.Fatal("the stop ran while another power action held the lock")
+	case <-time.After(100 * time.Millisecond):
+	}
+
+	close(env.release)
+
+	select {
+	case <-env.stops:
+	case <-time.After(2 * time.Second):
+		t.Fatal("the stop was dropped instead of waiting for the power lock")
+	}
+}