| Version |
|---|
| Docker client version 20.10.12 |
| Docker server version 20.10.12 |
docker version
docker info
docker top <container> - list running processes in specific container
docker container top
docker container inspect - show metadata about the container
docker container stats - show live performance data for all containers
docker run hello-world - create image if still dont have and run the image
docker run -d hello-world - create image if still dont have and run the image in the background
docker run -it <container> bash - start container interactively
docker create hello-world - create the image, it download from docker hub if still not exist
docker start hello-world - start the image without attach to it(cannot see the output)
docker start -a hello-world - start the image and attach to it so the output will show
docker ps - list active container
docker container ls - list active container
docker ps --all - list active and inactive container
docker system df - see space usage
docker image prune -a - remove unused images
docker start <container-id> - start the previous container(with previous image and previous command)
docker start -a <container-id> - start the previous container(with previous image and previous command) and able to see the output because of attach option
docker system prune - delete all stopped containers, delete networks not used, delete dangling images, delete all build cache
docker logs <container-id> - check the logs of the container, can use this to see output if running container without attach option
docker stop <container-id> - stop a container without force (SIGTERM)
docker kill <container-id> - stop a container with force (SIGKILL). Immediately kill it
docker exec -it <container-id> <command> - execute command inside running container. (-i allow to send input to the container, -t allow to see properly)
docker exec -it <container-id> sh - run shell inside the running container
docker exec -it <container-id> bash - run bash inside the running container
docker run -it <container-id> sh - run container with sh command
docker container port <container> - check container port
docker network ls
docker network inspect
docker network create --driver
docker network connect
docker network disconnect
docker inspect --format='{{ .NetworkSettings.IPAddress}}' <container>
docker image history <repository> - check image history
docker image inspect <repository> - inspect image
docker images - list all images
docker image tag <repository/image>:<tag> <repository/image>:<tag>
docker image push <repository/image>:<tag> - push image to registry(docker hub), need to login with docker login
docker volume create <name> - create volume
Dockerfile to create the image, Dockerfile contain FROM, RUN and CMD. below example
FROM alpine
RUN apk add --update redis
CMD ["redis-server"]docker build -t <docker-id>/<project-name>:<version> . - build a container with tag option, example docker build -t oyuu/testcontainer:latest
docker commit -c 'CMD ["<command>"]' <container-id> - build a container from another container with new command.
docker commit -c "CMD '<command>'" <container-id> - for windows, build a container from another container with new command.
docker run -p 8080:8080 <container-id> - running web application with port mapping, docker port mapping change when we running container not inside Dockerfile
below example Dockerfile webapp
#base image
FROM node:alpine
#working directory, any command after this lines will be inside this working directory
WORKDIR /usr/app
#copy files from the build folder to the container(inside working directory location). If the files inside build folder got changing, the build process will rerun the copy and after that instead of using caches.
COPY ./ ./
RUN npm install
CMD [ "npm","start"]below example Dockerfile webapp with improvement. the RUN command will not take longer time for build if files under ./ except package.json got changes.
#base image
FROM node:alpine
#working directory, any command after this lines will be inside this working directory
WORKDIR /usr/app
COPY --chown=node:node ./package.json ./
RUN npm install
COPY --chown=node:node ./ ./
CMD [ "npm","start"]below the output build process after the improvement
PS Y:\work\github\docker-and-kubernetes\simpleweb> docker build -t oyuu/simpleweb .
[+] Building 7.2s (11/11) FINISHED
=> [internal] load build definition from Dockerfile
=> => transferring dockerfile: 174B
=> [internal] load .dockerignore
=> => transferring context: 2B
=> [internal] load metadata for docker.io/library/node:alpine
=> [auth] library/node:pull token for registry-1.docker.io
=> [1/5] FROM docker.io/library/node:alpine@sha256:6f8ae702a7609f6f18d81ac72998e5d6f5d0ace9a13b866318c76340c6d986b2
=> [internal] load build context
=> => transferring context: 233B
=> CACHED [2/5] WORKDIR /usr/app
=> [3/5] COPY ./package.json ./
=> [4/5] RUN npm install
=> [5/5] COPY ./ ./
=> exporting to image
=> => exporting layers
=> => writing image sha256:3adb95dfee69603a642bf9d8fe95aa7c2d978878f16734e59e7c16b86c18220d
=> => naming to docker.io/oyuu/simpleweb
PS Y:\work\github\docker-and-kubernetes\simpleweb> docker build -t oyuu/simpleweb .
[+] Building 1.5s (10/10) FINISHED
=> [internal] load build definition from Dockerfile
=> => transferring dockerfile: 32B
=> [internal] load .dockerignore
=> => transferring context: 2B
=> [internal] load metadata for docker.io/library/node:alpine
=> [1/5] FROM docker.io/library/node:alpine@sha256:6f8ae702a7609f6f18d81ac72998e5d6f5d0ace9a13b866318c76340c6d986b2
=> [internal] load build context
=> => transferring context: 303B
=> CACHED [2/5] WORKDIR /usr/app
=> CACHED [3/5] COPY ./package.json ./
=> CACHED [4/5] RUN npm install
=> [5/5] COPY ./ ./
=> exporting to image
=> => exporting layers
=> => writing image sha256:f9d1d3afb4a6d783abff6a6e3dde9be1cffd08c82ee20a58fc548220cce58318
=> => naming to docker.io/oyuu/simpleweb
docker-compose - start up multiple docker containers at the same time, automates some of the long arguments that were passing to docker run
version: "3"
services:
redis-server:
image: "redis"
node-app:
build: . #build the dockerfile in current directory
ports:
- "4001:8081" #dash means array because can map many ports.docker-compose up - run docker-compose.yml at the current location
docker-compose up --build - run docker-compose.yml with the build option at the current location
docker-compose up -d - run docker-compose.yml in the background
docker-compose down - stop all container in the docker-compose.yml
restart policies in docker-compose, below detail and example nodejs app with process.exit(0), exit with code okay
"no" - never attemt to restart this container if stops or crashes
"always" - if this container stops for anyreason, always attempt to restart it
"on-failure" - only restart if the container stops with an error code(not "0")
"unless-stopped" - always restart unless the developer forcibly stop itconst express = require("express");
const redis = require("redis");
const app = express();
const client = redis.createClient({
host: "redis-server",
port: 6379,
});
client.set("visits", 0);
app.get("/", (req, res) => {
process.exit(0); //exit with 0 means everything is okay, with other value means something went wrong
client.get("visits", (err, visits) => {
res.send("Number of visits is " + visits);
client.set("visits", parseInt(visits) + 1);
});
});
app.listen(8081, () => {
console.log("Listening on port 8081");
});docker build -f Dockerfile.dev . - run docker build with specific Dockerfile name
docker run -v $(pwd):/app <image-id> - create a container with volume mapping current directory to container directory
docker run -v /app/node_modules -v $(pwd):/app <image-id> - -v /app/node_modules means dont map and keep using the container files
docker-compose.yml file with detail on build. for development purpose
version: "3"
services:
web:
build:
context: . #Dockerfile location
dockerfile: Dockerfile.dev #file name
ports:
- 3300:3000
volumes:
- /app/node_modules
- .:/appDockerfile example for production build
FROM node:16-alpine as builder
WORKDIR '/app'
COPY ./package.json .
RUN npm install
COPY ./ ./
RUN npm run build
FROM nginx
COPY --from=builder /app/build /usr/share/nginx/htmlcomplex exercise, below file tree and docker-compose.yml
complex
├── client
│ ├── Dockerfile.dev
│ ├── node_modules
│ ├── package.json
│ ├── public
│ │ ├── favicon.ico
│ │ ├── index.html
│ │ ├── logo192.png
│ │ ├── logo512.png
│ │ ├── manifest.json
│ │ └── robots.txt
│ ├── README.md
│ └── src
│ ├── App.css
│ ├── App.js
│ ├── App.test.js
│ ├── Fib.js
│ ├── index.css
│ ├── index.js
│ ├── logo.svg
│ ├── OtherPage.js
│ ├── serviceWorker.js
│ └── setupTests.js
├── docker-compose.yml
├── nginx
│ ├── default.conf
│ └── Dockerfile.dev
├── server
│ ├── Dockerfile.dev
│ ├── index.js
│ ├── keys.js
│ ├── node_modules
│ └── package.json
└── worker
├── Dockerfile.dev
├── index.js
├── keys.js
├── node_modules
└── package.json
9 directories, 30 files
version: "3"
services:
postgres:
image: "postgres:latest"
environment:
- POSTGRES_PASSWORD=postgres_password
redis:
image: "redis:latest"
nginx:
depends_on:
- api
- client
restart: always
build:
dockerfile: Dockerfile.dev
context: ./nginx
ports:
- "3300:80"
api:
build:
dockerfile: Dockerfile.dev
context: ./server
volumes:
- /app/node_modules
- ./server:/app
environment: #below information for keys.js inside server and worker folder
- REDIS_HOST=redis #from line no.7
- REDIS_PORT=6379 #check redis documentation
- PGUSER=postgres
- PGHOST=postgres
- PGDATABASE=postgres
- PGPASSWORD=postgres_password
- PGPORT=5432
client:
stdin_open: true
build:
dockerfile: Dockerfile.dev
context: ./client
volumes:
- /app/node_modules
- ./client:/app
worker:
build:
dockerfile: Dockerfile.dev
context: ./worker
volumes:
- /app/node_modules
- ./worker:/app
environment:
- REDIS_HOST=redis
- REDIS_PORT=6379