Mini-Microservices-App

Mini-Microservices com Arquitetura Assincronia com event bus (query service, emmiting events e receiving events). Stack: React.js Node.js com Express.

Docker quick notes

• alpine: small and compact as much as possible.
• docker run = docker create my-app-image + docker start -a
• -a : attach on terminal ou usar logs caso nao use o -a

docker run my-app-image
docker ps --all
docker stop <containerID> //stop giving some time
docker kill <containerID> //RIGHT NOW!
docker system prune
docker start <containerID> // sem -a.. usar log
docker logs <containerID>
docker push havyx/posts

• Abrir novo terminal, docker ps, pegar id
• -it para conseguir dar inpur no container

docker run redis
docker exec -it <containerID> redis-cli

• open shell inside container sh, bash etc

docker exec -it <containerID> sh
ls redis-cli etc
docker run -it container-image-name sh

• Criar Docker Images
• mkdir redis-image
• cd redis-image
• criar arquivo DockerFile

FROM alpine
RUN apk add --update redis
CMD ["redis-server"]

docker build .
docker run <containerID>

• TAG IMAGE

docker build -t yourDockerId/projectName:version .
docker build -t havyx/redis:latest .
docker run havyx/redis

• Nodejs Image

FROM node:alpine
COPY ./ ./
RUN npm install
CMD ["npm", "start"]

• PORT Forwarding

docker run -p portOutsideContainer : portInsideContainer <imageID>
docker run -p 8080 : 8080 <imageID>

• Working directory

FROM node:alpine
WORKDIR /usr/app
COPY ./ ./
RUN npm install
CMD ["npm", "start"]

• Rebuild BEST WAY Cache

FROM node:alpine
WORKDIR /usr/app
COPY ./package.json ./
RUN npm install
COPY ./ ./
CMD ["npm", "start"]

Kubernetes quick notes

• Kubernetes CLuster: A collections of nodes + a master to manage them
• Node: A virtual machine that will run our containers
• Pode : More or less a running container. A Pod can run multiple containers.
• Deployment: Monitors a set of pods, make sure they are running and restarts them if they crash.
• Provides an easy-to-remember URL to access a running container.

kubectl version
docker build -t havyx/posts:0.0.1 .

• Criar um pod com a .yaml file:

apiVersion: v1
kind: Pod
metadata:
  name: posts
spec:
  containers:
    - name: posts
      image: havyx/posts:0.0.1

kubectl apply -f posts.yaml
kubectl exec -it posts sh

Others commands:
kubectl get pods
kubectl exec -it [pod_name] [cmd]
kubectl logs [pod_name]
kubectl delete pod [pod_name]
kubectl apply -f [config file name]
kubectl describe pod [pod_name]

Deployment

kubectl get deplyments
kubectl describe deployment [depl name]
kubectl apply -f [config file name]
kubectl delete deployment [depl_name]
kubectl rollout restart deployment posts-depl

Services

• Cluster IP: Sets up an easy to remember URL to access a pod. Only exposes pods in the cluster.
• Node Port: Makes a pod accessible from outside the cluster. Usually only used for dev purposes.
• Load Balancer: Makes a pod accessible from outside the cluster. This is the right way to expose a pod to the outside world.
• External Name: Redirects an in-cluster request to a CNAME url.

Node Port -> For dev porpuses

kubectl apply -f posts-srv.yaml
kubectl get services
kubectl describe service posts-srv
4000:32087/TCP
A porta 32087 que acessamos por fora localhost:32087/posts
kubectl logs [podname]

Cluster IP

---
apiVersion: v1
kind: Service
metadata:
  name: event-bus-srv
spec:
  selector:
    app: event-bus
  type: ClusterIP
  ports:
    - name: event-bus
      protocol: TCP
      port: 4005
      targetPort: 4005

• aplicar config para todos os arquivos yaml em uma pasta:

kubectl apply -f .

Skaffold

skaffold dev