OKG add doc of ID awareness (#159)

Signed-off-by: ChrisLiu <[email protected]>

i18n/zh/docusaurus-plugin-content-docs-kruisegame/current/user-manuals/deploy-gameservers.md

@@ -1,5 +1,6 @@
 # 部署游戏服
-## 功能概述
+
+## "Hello World" of OKG
 您可以使用GameServerSet进行游戏服的部署，一个简单的部署案例如下：
 
 ```bash
@@ -30,14 +31,71 @@ NAME        AGE
 minecraft   9s
 
 kubectl get gs
-NAME          STATE   OPSSTATE   DP    UP
-minecraft-0   Ready   None       0     0
-minecraft-1   Ready   None       0     0
-minecraft-2   Ready   None       0     0
+NAME          STATE   OPSSTATE   DP    UP   AGE
+minecraft-0   Ready   None       0     0    10s
+minecraft-1   Ready   None       0     0    10s
+minecraft-2   Ready   None       0     0    10s
 
 kubectl get pod
 NAME            READY   STATUS    RESTARTS   AGE
 minecraft-0     1/1     Running   0          10s
 minecraft-1     1/1     Running   0          10s
 minecraft-2     1/1     Running   0          10s
-```
+```
+
+## ID业务感知
+
+游戏服由于有状态的特性，通常需要唯一标识来区别彼此，这也是GameServerSet管理的GameServer的名称会以ID序号结尾的原因。
+
+在有些情况下，游戏服业务自身需要感知到自己的ID，以作为区服属性标志或配置管理的依据等。
+这个时候，通过 DownwardAPI 可以实现将对应标识ID下沉至容器中。下面是一个示例：
+
+部署一个GameServerSet，其生成的游戏服容器中的环境变量GS_NAME会以对应名称为值：
+
+```yaml
+apiVersion: game.kruise.io/v1alpha1
+kind: GameServerSet
+metadata:
+  name: minecraft
+  namespace: default
+spec:
+  replicas: 3
+  updateStrategy:
+    rollingUpdate:
+      podUpdatePolicy: InPlaceIfPossible
+  gameServerTemplate:
+    spec:
+      containers:
+        - image: registry.cn-hangzhou.aliyuncs.com/acs/minecraft-demo:1.12.2
+          name: minecraft
+          env:
+          - name: GS_NAME
+            valueFrom:
+              fieldRef:
+                fieldPath: metadata.name
+```
+
+同样会生成3个游戏服：
+
+```bash
+kubectl get gs
+NAME          STATE   OPSSTATE   DP    UP    AGE
+minecraft-0   Ready   None       0     0     31s
+minecraft-1   Ready   None       0     0     31s
+minecraft-2   Ready   None       0     0     31s
+```
+
+分别查看这三个游戏服的GS_NAME环境变量，发现三个游戏服的GS_NAME与自身的名称一一对应。
+
+```bash
+kubectl exec  minecraft-0 -- env | grep GS_NAME
+GS_NAME=minecraft-0
+
+kubectl exec  minecraft-1 -- env | grep GS_NAME
+GS_NAME=minecraft-1
+
+kubectl exec  minecraft-2 -- env | grep GS_NAME
+GS_NAME=minecraft-2
+```
+
+这样一来，业务程序在启动时可以通过解析GS_NAME环境变量来进行配置管理等操作了。

kruisegame/user-manuals/deploy-gameservers.md

@@ -1,4 +1,6 @@
 # Deploy Gameservers
+
+## “Hello World” of OKG
 You can use GameServerSet to deploy game servers. A simple deployment case is as follows:
 
 ```bash
@@ -29,14 +31,72 @@ NAME        AGE
 minecraft   9s
 
 kubectl get gs
-NAME          STATE   OPSSTATE   DP    UP
-minecraft-0   Ready   None       0     0
-minecraft-1   Ready   None       0     0
-minecraft-2   Ready   None       0     0
+NAME          STATE   OPSSTATE   DP    UP   AGE
+minecraft-0   Ready   None       0     0    10s
+minecraft-1   Ready   None       0     0    10s
+minecraft-2   Ready   None       0     0    10s
 
 kubectl get pod
 NAME            READY   STATUS    RESTARTS   AGE
 minecraft-0     1/1     Running   0          10s
 minecraft-1     1/1     Running   0          10s
 minecraft-2     1/1     Running   0          10s
 ```
+
+
+## ID awareness
+
+Due to the stateful nature of game servers, they usually need unique identifiers to distinguish each other. This is why the name of the GameServer managed by GameServerSet ends with an ID number.
+
+In some cases, the game server business itself needs to be aware of its own ID, which can be used as a regional server attribute mark or a basis for configuration management.
+At this time, the corresponding identification ID can be sunk into the container through DownwardAPI. Here's an example:
+
+Deploy a GameServerSet, and the environment variable GS_NAME in the generated game server container will have the corresponding name as its value:
+
+```yaml
+apiVersion: game.kruise.io/v1alpha1
+kind: GameServerSet
+metadata:
+  name: minecraft
+  namespace: default
+spec:
+  replicas: 3
+  updateStrategy:
+    rollingUpdate:
+      podUpdatePolicy: InPlaceIfPossible
+  gameServerTemplate:
+    spec:
+      containers:
+        - image: registry.cn-hangzhou.aliyuncs.com/acs/minecraft-demo:1.12.2
+          name: minecraft
+          env:
+          - name: GS_NAME
+            valueFrom:
+              fieldRef:
+                fieldPath: metadata.name
+```
+
+3 game servers will be generated:
+
+```bash
+kubectl get gs
+NAME          STATE   OPSSTATE   DP    UP    AGE
+minecraft-0   Ready   None       0     0     31s
+minecraft-1   Ready   None       0     0     31s
+minecraft-2   Ready   None       0     0     31s
+```
+
+Check the GS_NAME environment variables of these three game servers separately and find that the GS_NAME of the three game servers corresponds to their own names.
+
+```bash
+kubectl exec  minecraft-0 -- env | grep GS_NAME
+GS_NAME=minecraft-0
+
+kubectl exec  minecraft-1 -- env | grep GS_NAME
+GS_NAME=minecraft-1
+
+kubectl exec  minecraft-2 -- env | grep GS_NAME
+GS_NAME=minecraft-2
+```
+
+In this way, the game program can perform configuration management and other operations by parsing the GS_NAME environment variable when it is started.