Docker Tutorial

# docker pull <image_name>
docker pull nginx

# docker run <image_name>
docker run nginx

# Common flag options:

# -d = detach, run in the background
docker run -d nginx

# --name = assign a name to the created container
docker run --name my-nginx nginx

# -p = port mapping
# example: map container’s port 80 to host’s port 8080
docker run -p 8080:80 nginx

# --rm = remove the container when it stops
docker run --rm nginx

# -e = set environment variables accessible to the app
docker run -e MYVAR=root nginx

# --network = specify which network the container will join
docker run --network nginx-network nginx

# --restart = container restart policy
# no -> default, container won’t restart when stopped
# always -> always restart the container when it stops
# on-failure -> restart only if the container exits with an error
docker run --restart always nginx

# --memory = set memory usage limit
# --cpus = set CPU usage limit
docker run --memory 512m --cpus 1.5 nginx

# -t <image_name>:<version> = assign a name and version to the image being built
# . (dot) at the end tells Docker where the Dockerfile is located
docker build -t my-app:1.0 .

# -f = specify a different Dockerfile
# by default, docker build looks for a file named "Dockerfile"
docker build -f custom.Dockerfile -t my-app .

# --build-arg = like -e on docker run, defines variables used in the Dockerfile
docker build --build-arg APP_ENV=production -t my-app .

# --no-cache = build without using cache
# by default, build uses cache to speed up subsequent builds
docker build --no-cache -t my-app .

# -a = also show stopped containers
docker ps -a

# list existing containers
docker container ls

# list existing images
docker image ls

# list existing networks
docker network ls

# list existing volumes
docker volume ls

docker system df

# example output:
TYPE            TOTAL     ACTIVE    SIZE      RECLAIMABLE
Images          29        6         10.28GB   7.843GB (76%)
Containers      6         4         150.3MB   148.9MB (99%)
Local Volumes   44        0         5.187kB   5.187kB (100%)
Build Cache     0         0         0B        0B

# remove stopped containers
docker container prune

# remove dangling images (temporary, cache)
docker image prune

# remove images not used by any container
docker image prune -a

# remove unused networks
docker network prune

# remove unused volumes
docker volume prune

# remove unused builder cache
docker builder prune

# remove all dangling containers, images, networks, builders (except volumes)
docker system prune

# remove all dangling containers, images, networks, builders, and volumes
docker system prune --volumes

# remove all unused containers, images, networks, builders, and volumes
docker system prune -a

# view logs from start to end
docker logs nginx

# -f = follow logs live in real time
docker logs nginx -f

# --tail = show last n lines of logs
docker logs --tail 10 nginx  # last 10 log lines

# docker exec <container> <command>
docker exec nginx pwd  # execute pwd inside nginx container

# -it = interactive + tty, usually combined when accessing shell
docker exec -it nginx bash
docker exec -it nginx sh

# -u <user> = execute command as specified user
docker exec -u root nginx pwd  # run pwd as root user

docker stats

# example output:
CONTAINER ID   NAME      CPU %     MEM USAGE / LIMIT     MEM %     NET I/O          BLOCK I/O         PIDS
35e6fdbdcd11   app       0.00%     309.4MiB / 15.45GiB   1.96%     634kB / 205kB    86.2MB / 1.68MB   42
4776744e7f8b   db-app    0.00%     9.953MiB / 15.45GiB   0.06%     332kB / 1.82kB   172kB / 1.16MB    13

project/
├── Dockerfile
├── nginx.conf
└── html/
    └── index.html

# Use the Nginx image as the base image
FROM nginx:latest

# Copy the Nginx configuration file into the container
COPY nginx.conf /etc/nginx/nginx.conf

# Copy the website files into the Nginx root directory
COPY html/ /usr/share/nginx/html/

# Expose port 80 for HTTP access
EXPOSE 80

# Command to run Nginx
CMD ["nginx", "-g", "daemon off;"]

events { }

http {
    server {
        listen 80;
        server_name localhost;

        location / {
            root /usr/share/nginx/html;
            index index.html;
        }

        error_page 404 /404.html;
    }
}

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Learning Dockerfile</title>
  </head>
  <body>
    <h1>Learning Dockerfile</h1>
  </body>
</html>

docker build -t coba-nginx-custom:1.0 .
docker run -d -p 80:80 --name my-application coba-nginx-custom:1.0

version: '3.9'
services:
  app:
    build: .
    image: coba-nginx-custom:1.0
    container_name: aplikasi-saya
    ports:
      - '80:80'

# build the image, same as `docker build -t coba-nginx-custom:1.0 .`
docker compose build

# run the container, similar to:
# docker run -d -p 80:80 --name aplikasi-saya coba-nginx-custom:1.0
docker compose up -d