云原生初體驗：在K8s上部署Springboot應用
作者： dafei1288
本文會在window環境下，構建一套基于k8s的istio環境，并且通過skaffold完成鏡像的構建和項目部署到集群環境。其實對于實驗環境有限的朋友們，完全可以在某里云上，按量付費搞3臺”突發性能實例“，玩一晚，也就是杯咖啡錢。
你會不會對“云原生”很有興趣，卻不知道從何入手?
本文會在window環境下，構建一套基于k8s的istio環境，并且通過skaffold完成鏡像的構建和項目部署到集群環境。其實對于實驗環境有限的朋友們，完全可以在某里云上，按量付費搞3臺”突發性能實例“，玩一晚，也就是杯咖啡錢。
好吧，讓我開始吧!
執行流程
整體流程的話，如下圖所示，通過 Skaffold+jib 將開發的應用打包成鏡像，提交到本地倉庫，并且將應用部署到集群中。k8s中部署2個pod，模擬應用不同的版本，并且配置訪問權重20%：80%。
環境選擇
我之前有文章詳細介紹過minikube。本次實驗，開始的時候，我就一直沉溺在使用kind的便捷上，而且直接可以在docker上部署集群，可以說非常方便。但是由于我對K8S的理解并不足夠，導致后面遇到了很多問題，所以，在這里建議新上手的小伙伴，還是使用minikube吧。k3s和RKE都需要多臺虛擬機，礙于機器性能，這種方案暫時不考慮了。
下面表格，對比了minikube、kind、k3s 部署環境，以及支持情況，方便大家選擇。
| minikube | kind | k3s | |
|---|---|---|---|
| runtime | VM | container | native |
| supported architectures | AMD64 | AMD64 | AMD64, ARMv7, ARM64 |
| supported container runtimes | Docker,CRI-O,containerd,gvisor | Docker | Docker, containerd |
| startup time initial/following | 5:19 / 3:15 | 2:48 / 1:06 | 0:15 / 0:15 |
| memory requirements | 2GB | 8GB (Windows, MacOS) | 512 MB |
| requires root? | no | no | yes (rootless is experimental) |
| multi-cluster support | yes | yes | no (can be achieved using containers) |
| multi-node support | no | yes | yes |
| project page | https://minikube.sigs.k8s.io/ | https://kind.sigs.k8s.io/ |
[1] 表格引用自：http://jiagoushi.pro/minikube-vs-kind-vs-k3s-what-should-i-use
docker desktop 沒有特殊要求。其他的自己用的順手就好，還是需要特別說一下minikube，別用最新的coredns一直都拉不下來，除非你的魔法，可以完全搞定，否則，還是用阿里編譯的minikube版本吧，別跟自己較勁，別問我為什么...
我用的版本羅列在下面了：
- ➜ ~ istioctl version
- client version: 1.10.2
- control plane version: 1.10.2
- data plane version: 1.10.2 (10 proxies)
- ➜ ~ minikube version
- minikube version: v1.18.1
- commit: 511aca80987826051cf1c6527c3da706925f7909
- ➜ ~ skaffold version
- v1.29.0
環境搭建
使用minikube創建集群
使用 hyperv 作為引擎 ， 內存 8192M cup 4核，不能再少了，否則拉不起來 istio。
- ➜ ~ minikube start --image-mirror-country='cn' --registry-mirror=https://hq0igpc0.mirror.aliyuncs.com --vm-driver="hyperv" --memory=8192 --cpus=4 --hyperv-virtual-switch="minikubeSwitch" --image-repository=registry.cn-hangzhou.aliyuncs.com/google_containers
還要在 hyperv里創建一個虛擬路由，這里我構建了一個內部網絡，這樣可以通過設置網卡的ip，將內部網絡的網段固定下來，否則，每次重啟都會變化ip。
配置讓內部網絡，共享訪問互聯網。
啟動成功：
- ➜ istio-1.10.2 minikube start
- 😄 Microsoft Windows 10 Pro 10.0.19042 Build 19042 上的 minikube v1.18.1
- 🎉 minikube 1.20.0 is available! Download it: https://github.com/kubernetes/minikube/releases/tag/v1.20.0
- ✨ 根據現有的配置文件使用 hyperv 驅動程序
- 👍 Starting control plane node minikube in cluster minikube
- 🔄 Restarting existing hyperv VM for "minikube" ...
- 🐳 正在 Docker 20.10.3 中準備 Kubernetes v1.20.2…
- 🔎 Verifying Kubernetes components...
- ▪ Using image registry.cn-hangzhou.aliyuncs.com/google_containers/storage-provisioner:v4 (global image repository)
- ▪ Using image registry.hub.docker.com/kubernetesui/dashboard:v2.1.0
- ▪ Using image registry.hub.docker.com/kubernetesui/metrics-scraper:v1.0.4
- ▪ Using image registry.cn-hangzhou.aliyuncs.com/google_containers/metrics-server-amd64:v0.2.1 (global image repository)
- 🌟 Enabled addons: metrics-server, storage-provisioner, dashboard, default-storageclass
- 🏄 Done! kubectl is now configured to use "minikube" cluster and "default" namespace by default
部署 istio
創建 istio-system 的命名空間
kubectl create namespace istio-system
安裝 istio
istioctl manifest apply --set profile=demo
安裝完成后，執行命令 kubectl get svc -n istio-system
- ➜ ~ kubectl get svc -n istio-system
- NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
- istio-egressgateway ClusterIP 10.105.31.73 <none> 80/TCP,443/TCP 8d
- istio-ingressgateway LoadBalancer 10.103.61.73 <pending> 15021:31031/TCP,80:31769/TCP,443:30373/TCP,31400:31833/TCP,15443:32411/TCP 8d
- istiod ClusterIP 10.110.109.205 <none> 15010/TCP,15012/TCP,443/TCP,15014/TCP 8d
部署 bookinfo
部署 bookinfo demo 驗證環境
執行命令
- kubectl label namespace default istio-injection=enabled
- kubectl apply -f samples/bookinfo/platform/kube/bookinfo.yaml
等待pod都啟動起來以后，添加bookinfo網絡配置，用于訪問 kubectl apply -f .\samples\bookinfo\networking\bookinfo-gateway.yaml
- ➜ istio-1.10.2 kubectl apply -f .\samples\bookinfo\networking\bookinfo-gateway.yaml
- gateway.networking.istio.io/bookinfo-gateway created
- virtualservice.networking.istio.io/bookinfo created
使用命令查看service : kubectl get services
- ➜ ~ kubectl get services
- NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
- callme-service NodePort 10.106.26.24 <none> 8080:30101/TCP 8d
- details ClusterIP 10.110.253.19 <none> 9080/TCP 8d
- kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 8d
- productpage ClusterIP 10.96.246.175 <none> 9080/TCP 8d
- ratings ClusterIP 10.99.234.109 <none> 9080/TCP 8d
- reviews ClusterIP 10.103.177.123 <none> 9080/TCP 8d
查看pods狀態 kubectl get pods
- ➜ ~ kubectl get pods
- NAME READY STATUS RESTARTS AGE
- callme-service-v1-76dd76ddcc-znb62 2/2 Running 0 4h59m
- callme-service-v2-679db76bbc-m4svm 2/2 Running 0 4h59m
- details-v1-79f774bdb9-qk9q8 2/2 Running 8 8d
- productpage-v1-6b746f74dc-p4xcb 2/2 Running 8 8d
- ratings-v1-b6994bb9-dlvjm 2/2 Running 8 8d
- reviews-v1-545db77b95-sgdzq 2/2 Running 8 8d
- reviews-v2-7bf8c9648f-t6s8z 2/2 Running 8 8d
- reviews-v3-84779c7bbc-4p8hv 2/2 Running 8 8d
查看集群ip 以及 端口
- ➜ ~ kubectl get po -l istio=ingressgateway -n istio-system -o 'jsonpath={.items[0].status.hostIP}'
- 192.168.137.115
- ➜ istio-1.10.2 kubectl get svc istio-ingressgateway -n istio-system
- NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
- istio-ingressgateway LoadBalancer 10.110.228.32 <pending> 15021:32343/TCP,80:30088/TCP,443:31869/TCP,31400:32308/TCP,15443:32213/TCP 3m17s
于是訪問地址： http://192.168.137.115:31769/productpage
我們 bookinfo 就部署成功了。接下來我們創建應用。
構建應用
構建一個普通的springboot工程,添加編譯插件，這里我們使用了本地的docker倉庫存儲鏡像。
- <build>
- <plugins>
- <plugin>
- <groupId>org.springframework.boot</groupId>
- <artifactId>spring-boot-maven-plugin</artifactId>
- <executions>
- <execution>
- <goals>
- <goal>build-info</goal>
- <goal>repackage</goal>
- </goals>
- </execution>
- </executions>
- </plugin>
- <plugin>
- <groupId>com.google.cloud.tools</groupId>
- <artifactId>jib-maven-plugin</artifactId>
- <version>3.1.1</version>
- <configuration>
- <to>
- <image>127.0.0.1:9001/${project.artifactId}:${project.version}</image>
- <auth>
- <username>
- xxx
- </username>
- <password>
- xxx
- </password>
- </auth>
- </to>
- <allowInsecureRegistries>true</allowInsecureRegistries>
- </configuration>
- </plugin>
- </plugins>
- </build>
構建一個簡單的rest，現實一個構建名稱，以及配置的一個版本號。
- @Autowired
- BuildProperties buildProperties;
- @Value("${VERSION}")
- private String version;
- @GetMapping("/ping")
- public String ping() {
- LOGGER.info("Ping: name={}, version={}", buildProperties.getName(), version);
- return "I'm callme-service " + version;
- }
創建 skaffold.xml 用于給 skafflod 編譯鏡像，提交集群使用。
- kind: Config
- build:
- artifacts:
- - image: 127.0.0.1:9001/callme-service
- jib: {}
- tagPolicy:
- gitCommit: {}
創建k8s的部署描述k8s/deployment.yml，以及service用于訪問。
- apiVersion: apps/v1
- kind: Deployment
- metadata:
- name: callme-service-v1
- spec:
- replicas: 1
- selector:
- matchLabels:
- app: callme-service
- version: v1
- template:
- metadata:
- labels:
- app: callme-service
- version: v1
- spec:
- containers:
- - name: callme-service
- image: 127.0.0.1:9001/callme-service
- imagePullPolicy: IfNotPresent
- ports:
- - containerPort: 8080
- env:
- - name: VERSION
- value: "v1"
- ---
- apiVersion: apps/v1
- kind: Deployment
- metadata:
- name: callme-service-v2
- spec:
- replicas: 1
- selector:
- matchLabels:
- app: callme-service
- version: v2
- template:
- metadata:
- labels:
- app: callme-service
- version: v2
- spec:
- containers:
- - name: callme-service
- image: 127.0.0.1:9001/callme-service
- imagePullPolicy: IfNotPresent
- ports:
- - containerPort: 8080
- env:
- - name: VERSION
- value: "v2"
- ---
- apiVersion: v1
- kind: Service
- metadata:
- name: callme-service
- labels:
- app: callme-service
- spec:
- type: NodePort
- ports:
- - port: 8080
- name: http
- nodePort: 30101
- selector:
- app: callme-service
創建 istio描述文件 k8s\istio-rules.yaml：
- apiVersion: networking.istio.io/v1beta1
- kind: DestinationRule
- metadata:
- name: callme-service-destination
- spec:
- host: callme-service
- subsets:
- - name: v1
- labels:
- version: v1
- - name: v2
- labels:
- version: v2
- # trafficPolicy: # --- enable for adding circuit breaker into DestinationRule
- # connectionPool:
- # http:
- # http1MaxPendingRequests: 1
- # maxRequestsPerConnection: 1
- # maxRetries: 0
- # outlierDetection:
- # consecutive5xxErrors: 3
- # interval: 30s
- # baseEjectionTime: 1m
- # maxEjectionPercent: 100
- ---
- apiVersion: networking.istio.io/v1beta1
- kind: VirtualService
- metadata:
- name: callme-service-route
- spec:
- hosts:
- - callme-service
- http:
- - route:
- - destination:
- host: callme-service
- subset: v2
- weight: 80
- - destination:
- host: callme-service
- subset: v1
- weight: 20
- retries:
- attempts: 3
- retryOn: gateway-error,connect-failure,refused-stream
- timeout: 0.5s
- # fault: # --- enable for inject fault into the route
- # delay:
- # percentage:
- # value: 33
- # fixedDelay: 3s
運行 skaffold 進行編譯，提交鏡像，并部署應用 skaffold run --tail。
- ➜ callme-service git:(master) ✗ skaffold run --tail
- Generating tags...
- - 127.0.0.1:9001/callme-service -> 127.0.0.1:9001/callme-service:e9c731f-dirty
- Checking cache...
- - 127.0.0.1:9001/callme-service: Found Locally
- Starting test...
- Tags used in deployment:
- - 127.0.0.1:9001/callme-service -> 127.0.0.1:9001/callme-service:60f1bf39367673fd0d30ec1305d8a02cb5a1ed43cf6603e767a98dc0523c65f3
- Starting deploy...
- - deployment.apps/callme-service-v1 configured
- - deployment.apps/callme-service-v2 configured
- - service/callme-service configured
- - destinationrule.networking.istio.io/callme-service-destination configured
- - virtualservice.networking.istio.io/callme-service-route configured
- Waiting for deployments to stabilize...
- - deployment/callme-service-v1: waiting for init container istio-init to start
- - pod/callme-service-v1-76dd76ddcc-znb62: waiting for init container istio-init to start
- - deployment/callme-service-v2: waiting for init container istio-init to start
- - pod/callme-service-v2-679db76bbc-m4svm: waiting for init container istio-init to start
- - deployment/callme-service-v2 is ready. [1/2 deployment(s) still pending]
- - deployment/callme-service-v1 is ready.
- Deployments stabilized in 45.671 seconds
訪問查看結果：
致此，我們初級的環境搭建基本完成了，對應云原生，感覺懂了一點，好像又沒有懂，需要理解的東西還有很多，這個系列也會持續下去，希望大家和我交流，也歡迎關注，轉發。
參考鏈接;
https://piotrminkowski.com/2020/02/14/local-java-development-on-kubernetes/
https://pklinker.medium.com/integrating-a-spring-boot-application-into-an-istio-service-mesh-a55948666fd
https://blog.csdn.net/xixingzhe2/article/details/88537038
https://blog.csdn.net/chenleiking/article/details/86716049
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責任編輯：武曉燕
來源：
麒思妙想
