Metadata propagation from fleet allocation to game server

In the fleet allocation configuration you can add optional custom metadata that will be added to the game server in the moment of allocation

Author: Victor Prodan

examples/fleetallocation.yaml

@@ -28,4 +28,11 @@ metadata:
 spec:
   # The name of the fleet to allocate from. Must be an existing Fleet in the same namespace
   # as this FleetAllocation
-  fleetName: fleet-example
+  fleetName: fleet-example
+  # Custom metadata that is added to game server status in the moment of allocation
+  # You can use this to tell the server necessary session data
+  metadata:
+    labels:
+      mode: deathmatch
+    annotations:
+      map:  garden22

pkg/apis/stable/v1alpha1/fleetallocation.go

@@ -42,7 +42,14 @@ type FleetAllocationList struct {
 // FleetAllocationSpec is the spec for a Fleet
 // Allocation
 type FleetAllocationSpec struct {
-	FleetName string `json:"fleetName"`
+	FleetName string              `json:"fleetName"`
+	MetaPatch FleetAllocationMeta `json:"metadata,omitempty"`
+}
+
+// FleetAllocationMeta is the metadata used to patch the GameServer metadata on allocation
+type FleetAllocationMeta struct {
+	Labels      map[string]string `json:"labels,omitempty"`
+	Annotations map[string]string `json:"annotations,omitempty"`
 }
 
 // FleetAllocationStatus will contain the

pkg/fleetallocation/controller.go

@@ -134,7 +134,7 @@ func (c *Controller) creationMutationHandler(review admv1beta1.AdmissionReview)
 		return review, errors.Wrapf(err, "error retrieving fleet %s", fa.Name)
 	}
 
-	gs, err := c.allocate(fleet)
+	gs, err := c.allocate(fleet, &fa.Spec.MetaPatch)
 	if err != nil {
 		review.Response.Allowed = false
 		review.Response.Result = &metav1.Status{
@@ -250,7 +250,7 @@ func (c *Controller) mutationValidationHandler(review admv1beta1.AdmissionReview
 }
 
 // allocate allocated a GameServer from a given Fleet
-func (c *Controller) allocate(f *stablev1alpha1.Fleet) (*stablev1alpha1.GameServer, error) {
+func (c *Controller) allocate(f *stablev1alpha1.Fleet, fam *stablev1alpha1.FleetAllocationMeta) (*stablev1alpha1.GameServer, error) {
 	var allocation *stablev1alpha1.GameServer
 	// can only allocate one at a time, as we don't want two separate processes
 	// trying to allocate the same GameServer to different clients
@@ -280,6 +280,10 @@ func (c *Controller) allocate(f *stablev1alpha1.Fleet) (*stablev1alpha1.GameServ
 	gsCopy := allocation.DeepCopy()
 	gsCopy.Status.State = stablev1alpha1.Allocated
 
+	if fam != nil {
+		c.patchMetadata(gsCopy, fam)
+	}
+
 	gs, err := c.gameServerGetter.GameServers(f.ObjectMeta.Namespace).Update(gsCopy)
 	if err != nil {
 		return gs, errors.Wrapf(err, "error updating GameServer %s", gsCopy.ObjectMeta.Name)
@@ -288,3 +292,25 @@ func (c *Controller) allocate(f *stablev1alpha1.Fleet) (*stablev1alpha1.GameServ
 
 	return gs, nil
 }
+
+// patch the labels and annotations of an allocated GameServer with metadata from a FleetAllocation
+func (c *Controller) patchMetadata(gs *stablev1alpha1.GameServer, fam *stablev1alpha1.FleetAllocationMeta) {
+	// patch ObjectMeta labels
+	if fam.Labels != nil {
+		if gs.ObjectMeta.Labels == nil {
+			gs.ObjectMeta.Labels = make(map[string]string, len(fam.Labels))
+		}
+		for key, value := range fam.Labels {
+			gs.ObjectMeta.Labels[key] = value
+		}
+	}
+	// apply annotations patch
+	if fam.Annotations != nil {
+		if gs.ObjectMeta.Annotations == nil {
+			gs.ObjectMeta.Annotations = make(map[string]string, len(fam.Annotations))
+		}
+		for key, value := range fam.Annotations {
+			gs.ObjectMeta.Annotations[key] = value
+		}
+	}
+}

pkg/fleetallocation/controller_test.go

@@ -144,6 +144,10 @@ func TestControllerAllocate(t *testing.T) {
 	f, gsSet, gsList := defaultFixtures(4)
 	c, m := newFakeController()
 	n := metav1.Now()
+	l := map[string]string{"mode": "deathmatch"}
+	a := map[string]string{"map": "searide"}
+	fam := &v1alpha1.FleetAllocationMeta{Labels: l, Annotations: a}
+
 	gsList[3].ObjectMeta.DeletionTimestamp = &n
 
 	m.AgonesClient.AddReactor("list", "fleets", func(action k8stesting.Action) (bool, runtime.Object, error) {
@@ -172,25 +176,35 @@ func TestControllerAllocate(t *testing.T) {
 	_, cancel := agtesting.StartInformers(m)
 	defer cancel()
 
-	gs, err := c.allocate(f)
+	gs, err := c.allocate(f, fam)
 	assert.Nil(t, err)
 	assert.Equal(t, v1alpha1.Allocated, gs.Status.State)
 	assert.True(t, updated)
+	for key, value := range fam.Labels {
+		v, ok := gs.ObjectMeta.Labels[key]
+		assert.True(t, ok)
+		assert.Equal(t, v, value)
+	}
+	for key, value := range fam.Annotations {
+		v, ok := gs.ObjectMeta.Annotations[key]
+		assert.True(t, ok)
+		assert.Equal(t, v, value)
+	}
 
 	updated = false
-	gs, err = c.allocate(f)
+	gs, err = c.allocate(f, nil)
 	assert.Nil(t, err)
 	assert.Equal(t, v1alpha1.Allocated, gs.Status.State)
 	assert.True(t, updated)
 
 	updated = false
-	gs, err = c.allocate(f)
+	gs, err = c.allocate(f, nil)
 	assert.Nil(t, err)
 	assert.Equal(t, v1alpha1.Allocated, gs.Status.State)
 	assert.True(t, updated)
 
 	updated = false
-	_, err = c.allocate(f)
+	_, err = c.allocate(f, nil)
 	assert.NotNil(t, err)
 	assert.Equal(t, ErrNoGameServerReady, err)
 	assert.False(t, updated)
@@ -230,7 +244,7 @@ func TestControllerAllocateMutex(t *testing.T) {
 	allocate := func() {
 		defer wg.Done()
 		for i := 1; i <= 10; i++ {
-			_, err := c.allocate(f)
+			_, err := c.allocate(f, nil)
 			assert.Nil(t, err)
 		}
 	}