12-factors-with-docker-code-samples

02-dependencies.diff

const app = express()
const port = 3000
 
-app.get('/', (req, res) => res.send('Hello World!'))
+app.get('/', (req, res) => res.send('Hello World 2.0.0!'))
 
app.listen(port, () => console.log(`Example app listening on port ${port}!`))

02-dependencies.dockerfile

FROM node:13.3.0

WORKDIR /app

RUN apt-get update && apt-get install -y git

COPY package.json package-lock.json /app/

RUN npm ci

COPY . /app

EXPOSE 3000

CMD ["npm", "run", "serve"]

02-dependencies.sh

$ make build
docker build -t tonysm/node-app-docker:2.0.0 .
Sending build context to Docker daemon  2.065MB
Step 1/8 : FROM node:13.3.0
 ---> 2af77b226ea7
Step 2/8 : WORKDIR /app
 ---> Using cache
 ---> 07c5be8e9cde
Step 3/8 : RUN apt-get update && apt-get install -y git
 ---> Using cache
 ---> 9285fc2a80c2
Step 4/8 : COPY package.json package-lock.json /app/
 ---> Using cache
 ---> b5fb084d0c2a
Step 5/8 : RUN npm ci
 ---> Using cache
 ---> 19482a7d821a
Step 6/8 : COPY . /app
 ---> e1e469c7e35c
Step 7/8 : EXPOSE 3000
 ---> Running in 3f19795b571f
Removing intermediate container 3f19795b571f
 ---> ad14d5378b2d
Step 8/8 : CMD ["npm", "run", "serve"]
 ---> Running in dfa2ff542a49
Removing intermediate container dfa2ff542a49
 ---> 280c53c0f03d
Successfully built 280c53c0f03d
Successfully tagged tonysm/node-app-docker:2.0.0

03-docker-compose.yml

version: '3'

services:
  app:
    build: tonysm/myapp:1.0.0
    ports:
      - "80:80"
    environment:
      APP_NAME: "Laravel"

03-docker-run.sh

docker run --rm -e "APP_NAME=Laravel" tonysm/myapp:1.0.0

03-k8s-deploys.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-deploy
spec:
  selector:
    matchLabels:
      app: myapp-pod
  template:
    metadata:
      labels:
        app: myapp-pod
    spec:
      imagePullSecrets:
        - name: regcred
      containers:
        - envFrom:
            - secretRef:
                name: myapp-secrets
          name: myapp-app
          image: tonysm/myapp:1.0.0
          ports:
            - containerPort: 80

03-k8s-secrets.yml

apiVersion: v1
kind: Secret
metadata:
  name: myapp-secrets
type: Opaque
stringData:
  APP_NAME: "Laravel"

07-app.js

const app = express()
const port = 3000
 
app.get('/', (req, res) => res.send('Hello World!'))

app.listen(port, () => console.log(`Example app listening on port ${port}!`))

07-docker-run.sh

docker run --rm -it -p "3000:3000" tonysm/myapp:1.0.0

07-file.dockerfile

# ...

EXPOSE 3000

# ...

07-k8s-service.yml

apiVersion: v1
kind: Service
metadata:
  name: myapp-svc
spec:
  ports:
    - port: 80
      targetPort: 3000
  selector:
    app: myapp-pod

08-docker-compose.yml

version: '3.7'

services:
  web:
    image: tonysm/laravel-app:1.0.0
    ports:
      - "80:80"
    deploy:
      replicas: 2
  worker:
    image: tonysm/laravel-app:1.0.0
    command: php artisan queue:work --tries=3
    deploy:
      replicas: 4
  scheduler:
    image: tonysm/laravel-app:1.0.0
    command: php artisan scheduler:run
    deploy:
      replicas: 1
      update_config:
        order: stop-first # we don't want 2 schedulers running
        delay: 60s # it tells Swarm to try running it every minute
      restart_policy:
        condition: any # since the command exists, it should keep restarting it