GameServerSet Implementation

GameServerSets are the basic building block for Fleets.
GameServerSets will be allow Fleet migrations to occur, similarly
to how ReplicaSets allow Deployments to migrate one image type
to another.

This has not been formally documented, as this will likely be an
internal CRD, and not (widely) used externally.

Parent ticket: #70

cmd/controller/main.go

@@ -26,6 +26,7 @@ import (
 	"agones.dev/agones/pkg/client/clientset/versioned"
 	"agones.dev/agones/pkg/client/informers/externalversions"
 	"agones.dev/agones/pkg/gameservers"
+	"agones.dev/agones/pkg/gameserversets"
 	"agones.dev/agones/pkg/util/runtime"
 	"agones.dev/agones/pkg/util/signals"
 	"agones.dev/agones/pkg/util/webhooks"
@@ -128,7 +129,8 @@ func main() {
 	agonesInformerFactory := externalversions.NewSharedInformerFactory(agonesClient, 30*time.Second)
 	kubeInformationFactory := informers.NewSharedInformerFactory(kubeClient, 30*time.Second)
 
-	c := gameservers.NewController(wh, health, minPort, maxPort, sidecarImage, alwaysPullSidecar, kubeClient, kubeInformationFactory, extClient, agonesClient, agonesInformerFactory)
+	gsController := gameservers.NewController(wh, health, minPort, maxPort, sidecarImage, alwaysPullSidecar, kubeClient, kubeInformationFactory, extClient, agonesClient, agonesInformerFactory)
+	gsSetController := gameserversets.NewController(wh, health, kubeClient, extClient, agonesClient, agonesInformerFactory)
 
 	stop := signals.NewStopChannel()
 
@@ -140,6 +142,18 @@ func main() {
 			logger.WithError(err).Fatal("could not run webhook server")
 		}
 	}()
+	go func() {
+		err = gsController.Run(2, stop)
+		if err != nil {
+			logger.WithError(err).Fatal("Could not run gameserver controller")
+		}
+	}()
+	go func() {
+		err = gsSetController.Run(2, stop)
+		if err != nil {
+			logger.WithError(err).Fatal("Could not run gameserverset controller")
+		}
+	}()
 	go func() {
 		logger.Info("Starting health check...")
 		srv := &http.Server{
@@ -158,10 +172,6 @@ func main() {
 		}
 	}()
 
-	err = c.Run(2, stop)
-	if err != nil {
-		logger.WithError(err).Fatal("Could not run gameserver controller")
-	}
-
-	logger.Info("Shut down gameserver controller")
+	<-stop
+	logger.Info("Shut down agones controllers")
 }

examples/cpp-simple/gameserverset.yaml

@@ -0,0 +1,33 @@
+# Copyright 2018 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Usually you would define a Fleet rather than a GameServerSet
+# directly. This is here mostly for testing purposes
+
+apiVersion: "stable.agones.dev/v1alpha1"
+kind: GameServerSet
+metadata:
+  name: cpp-simple
+spec:
+  replicas: 5
+  template:
+    spec:
+      containerPort: 7654
+      template:
+        spec:
+          health:
+            initialDelaySeconds: 15
+          containers:
+            - name: cpp-simple
+              image: gcr.io/agones-images/cpp-simple-server:0.1

examples/simple-udp/server/gameserverset.yaml

@@ -0,0 +1,31 @@
+# Copyright 2018 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Usually you would define a Fleet rather than a GameServerSet
+# directly. This is here mostly for testing purposes
+
+apiVersion: "stable.agones.dev/v1alpha1"
+kind: GameServerSet
+metadata:
+  name: simple-udp
+spec:
+  replicas: 2
+  template:
+    spec:
+      containerPort: 7654
+      template:
+        spec:
+          containers:
+          - name: simple-udp
+            image: gcr.io/agones-images/udp-server:0.1

install/yaml/install.yaml

@@ -125,6 +125,34 @@ spec:
                   minimum: 1
                   maximum: 2147483648
 ---
+apiVersion: apiextensions.k8s.io/v1beta1
+kind: CustomResourceDefinition
+metadata:
+  name: gameserversets.stable.agones.dev
+spec:
+  group: stable.agones.dev
+  version: v1alpha1
+  scope: Namespaced
+  names:
+    kind: GameServerSet
+    plural: gameserversets
+    shortNames:
+    - gss
+    - gsset
+    singular: gameserverset
+  validation:
+    openAPIV3Schema:
+      properties:
+        spec:
+          required:
+            - replicas
+            - template
+          properties:
+            replicas:
+              type: integer
+              minimum: 0
+            template:
+---
 apiVersion: extensions/v1beta1
 kind: Deployment
 metadata:
@@ -218,6 +246,14 @@ webhooks:
           - "v1alpha1"
         operations:
           - CREATE
+      - apiGroups:
+          - stable.agones.dev
+        resources:
+          - "gameserversets"
+        apiVersions:
+          - "v1alpha1"
+        operations:
+          - UPDATE
 ---
 # Service account, secret, role and rolebinding for sidecar (agones-sdk) pod
 apiVersion: v1
@@ -296,8 +332,8 @@ rules:
   resources: ["customresourcedefinitions"]
   verbs: ["get"]
 - apiGroups: ["stable.agones.dev"]
-  resources: ["gameservers"]
-  verbs: ["delete", "get", "list", "update", "watch"]
+  resources: ["gameservers", "gameserversets"]
+  verbs: ["create", "delete", "get", "list", "update", "watch"]
 ---
 apiVersion: rbac.authorization.k8s.io/v1
 kind: ClusterRoleBinding

pkg/apis/stable/v1alpha1/types.go → pkg/apis/stable/v1alpha1/gameserver.go

@@ -44,6 +44,8 @@ const (
 	Error State = "Error"
 	// Unhealthy is when the GameServer has failed its health checks
 	Unhealthy State = "Unhealthy"
+	// Allocated is when the GameServer has been allocated to a session
+	Allocated State = "Allocated"
 
 	// Static PortPolicy means that the user defines the hostPort to be used
 	// in the configuration.
@@ -85,6 +87,22 @@ type GameServer struct {
 	Status GameServerStatus `json:"status"`
 }
 
+// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
+
+// GameServerList is a list of GameServer resources
+type GameServerList struct {
+	metav1.TypeMeta `json:",inline"`
+	metav1.ListMeta `json:"metadata,omitempty"`
+
+	Items []GameServer `json:"items"`
+}
+
+// GameServerTemplateSpec is a template for GameServers
+type GameServerTemplateSpec struct {
+	metav1.ObjectMeta `json:"metadata,omitempty"`
+	Spec              GameServerSpec `json:"spec"`
+}
+
 // GameServerSpec is the spec for a GameServer resource
 type GameServerSpec struct {
 	// Container specifies which Pod container is the game server. Only required if there is more than one
@@ -135,16 +153,6 @@ type GameServerStatus struct {
 	NodeName string `json:"nodeName"`
 }
 
-// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
-
-// GameServerList is a list of GameServer resources
-type GameServerList struct {
-	metav1.TypeMeta `json:",inline"`
-	metav1.ListMeta `json:"metadata,omitempty"`
-
-	Items []GameServer `json:"items"`
-}
-
 // ApplyDefaults applies default values to the GameServer if they are not already populated
 func (gs *GameServer) ApplyDefaults() {
 	gs.ObjectMeta.Finalizers = append(gs.ObjectMeta.Finalizers, stable.GroupName)

pkg/apis/stable/v1alpha1/gameserverset.go

@@ -0,0 +1,112 @@
+// Copyright 2018 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package v1alpha1
+
+import (
+	"reflect"
+
+	"agones.dev/agones/pkg/apis/stable"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+const (
+	// GameServerSetGameServerLabel is the label that the name of the GameServerSet
+	// is set on the GameServer the GameServerSet controls
+	GameServerSetGameServerLabel = stable.GroupName + "/gameserverset"
+)
+
+// +genclient
+// +genclient:noStatus
+// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
+
+// GameServerSet is the data structure a set of GameServers
+// This matches philosophically with the relationship between
+// Depoyments and ReplicaSets
+type GameServerSet struct {
+	metav1.TypeMeta   `json:",inline"`
+	metav1.ObjectMeta `json:"metadata,omitempty"`
+
+	Spec   GameServerSetSpec   `json:"spec"`
+	Status GameServerSetStatus `json:"status"`
+}
+
+// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
+
+// GameServerSetList is a list of GameServerSet resources
+type GameServerSetList struct {
+	metav1.TypeMeta `json:",inline"`
+	metav1.ListMeta `json:"metadata,omitempty"`
+
+	Items []GameServerSet `json:"items"`
+}
+
+// GameServerSetSpec the specification for
+type GameServerSetSpec struct {
+	// Replicas are the number of GameServers that should be in this set
+	Replicas int32 `json:"replicas"`
+	// Template the GameServer template to apply for this GameServerSet
+	Template GameServerTemplateSpec `json:"template"`
+}
+
+// GameServerSetStatus is the status of a GameServerSet
+type GameServerSetStatus struct {
+	// Replicas the total number of current GameServer replicas
+	Replicas int32 `json:"replicas"`
+	// ReadyReplicas are the number of Ready GameServer replicas
+	ReadyReplicas int32 `json:"readyReplicas"`
+}
+
+// ValidateUpdate validates when updates occur. The argument
+// is the new GameServerSet, being passed into the old GameServerSet
+func (gsSet *GameServerSet) ValidateUpdate(new *GameServerSet) (bool, []metav1.StatusCause) {
+	var causes []metav1.StatusCause
+	if !reflect.DeepEqual(gsSet.Spec.Template, new.Spec.Template) {
+		causes = append(causes, metav1.StatusCause{
+			Type:    metav1.CauseTypeFieldValueInvalid,
+			Field:   "template",
+			Message: "template values cannot be updated after creation",
+		})
+	}
+
+	return len(causes) == 0, causes
+}
+
+// GameServer returns a single GameServer derived
+// from the GameSever template
+func (gsSet *GameServerSet) GameServer() *GameServer {
+	gs := &GameServer{
+		ObjectMeta: *gsSet.Spec.Template.ObjectMeta.DeepCopy(),
+		Spec:       *gsSet.Spec.Template.Spec.DeepCopy(),
+	}
+
+	// Switch to GenerateName, so that we always get a Unique name for the GameServer, and there
+	// can be no collisions
+	gs.ObjectMeta.GenerateName = gsSet.ObjectMeta.Name + "-"
+	gs.ObjectMeta.Name = ""
+	gs.ObjectMeta.Namespace = gsSet.ObjectMeta.Namespace
+	gs.ObjectMeta.ResourceVersion = ""
+	gs.ObjectMeta.UID = ""
+
+	ref := metav1.NewControllerRef(gsSet, SchemeGroupVersion.WithKind("GameServerSet"))
+	gs.ObjectMeta.OwnerReferences = append(gs.ObjectMeta.OwnerReferences, *ref)
+
+	if gs.ObjectMeta.Labels == nil {
+		gs.ObjectMeta.Labels = make(map[string]string, 1)
+	}
+
+	gs.ObjectMeta.Labels[GameServerSetGameServerLabel] = gsSet.ObjectMeta.Name
+
+	return gs
+}