Docker Workflow

Docker Commands

# -------------------------------------------------------------------------------------------------------------------------
#               DOCKER
#
#      https://docs.docker.com/
#
# AWS ECR (Elastic Container Registry) used to store different versions of the same image (tags)
# image is like a template, and a container is what uses the template to start an environment you can interact with
# -------------------------------------------------------------------------------------------------------------------------

docker pull "image_name:version"                        # default is to pull from dockerhub

docker images                                           # list of images "prune" arg after images will delete all unused

docker run -d "image_name:version"                      # startup an image_name:version (or can use its hash)

docker ps -a                                            # list all containers

docker stats                                            # list all RUNNING containers and their status

docker network ls                                       # list all networks and their status

docker logs "container_name"                            # show logs for container_name (or can use its hash)

docker exec -it "container_name" /bin/bash              # open bash shell of container image (sometimes it's /bin/sh

docker stop "container_name"                            # stops a container with container_name (or can use its hash)

docker rm -f "container_name"                           # delete container with container_name (or can use its hash)

docker rmi "image_name:version"                         # delete image (all containers using must be stopped & deleted first)

docker build .                                          # build an image based on the Dockerfile in the current dir

docker tag "image_name" "image_name:version"            # take existing built image and tag for push to repo
                                                        # use AWS docker login to login first
                                                        # then use as image_name:version -> ...amazon.com/image_name:version

docker build -t "image_name:version" .                  # build & tag an image based on the Dockerfile in the current dir
                                                        # use ...amazon.com/image_name:version for AWS ECR publishing

docker push "image_name:version"                        # use ...amazon.com/image_name:version for AWS ECR publishing

docker system prune -a                                  # Clear docker system & cache of all images/containers/volumes

# -------------------------------------------------------------------------------------------------------------------------
#               DOCKER-COMPOSE
#
# https://docs.docker.com/compose/compose-file/compose-file-v3/
#
# -------------------------------------------------------------------------------------------------------------------------

docker-compose -f "docker-compose.yml" up               # builds & starts container based on the docker-compose.yaml config
                                                        # add -d at end to force into background on start

docker-compose -f "docker-compose.yml" down             # stops container of images based on the docker-compose.yaml config



# -------------------------------------------------------------------------------------------------------------------------
#               VOLUMES
#
# https://docs.docker.com/storage/volumes/
#
# -------------------------------------------------------------------------------------------------------------------------

docker volume create      \                             # creates host stored volume named "volume_name"
  --driver local          \                             # default is local, so can skip it, otherwise check
                                                        #https://docs.docker.com/storage/storagedriver/select-storage-driver/
  --name "volume_name"    \                             # used in docker-compose.yaml as named volume
  --label "volume_label"  \                             # optional -- like alias to override OS designated volume IDs
  --opt ""                                              # optional -- linux volume type, device, size, etc...
                                                        

docker volume ls                                        # list all volumes

docker volume inspect "volume_name" | "container_name"  # show volume config, including location of data on host

docker volume rm "volume_name"                          # delete volume

# -------------------------------------------------------------------------------------------------------------------------
#               LINKS
# -------------------------------------------------------------------------------------------------------------------------

Node Live Reload: https://www.freecodecamp.org/news/how-to-enable-live-reload-on-docker-based-applications/

docker-compose.yaml

# Instructions to build a CONTAINER
# more info at https://docs.docker.com/compose/compose-file/compose-file-v3/
# and at https://docs.docker.com/engine/reference/run/

version: '2'
  services:
    webapp_db:
      container_name: "webapp_db:1.0"            # use ...amazon.com/image_name:version for AWS ECR published images
      image: mysql:9.0.1
      networks:
        - webapp_network
      ports:
        - "3336:3306"                            # host:container
      environment:
        - MYSQL_ROOT_PASSWORD=password
        - MYSQL_USER=user
        - MYSQL_PASSWORD=password
        - MYSQL_DATABASE=demodb
      volumes:
        - db_data:
                                                 # data in db_data on host will be replicated in container at each run
    webapp:
      container_name: "webapp:1.0"               # use ...amazon.com/image_name:version for AWS ECR published images
      build: 
        - context: /path/to/DockerfileDirectory
        - dockerfile: DockerfileFileName
      networks:
        - webapp_network
      ports:
        - "8080:80"                              # host:container
      volumes:
        - /path/from/host:/path/to/container     #host volume -- great for dev live-reload of changes to code
        - container_n: /path/to/docker/namedvol  #named volume -- best for production
        - /path/to/docker/anonvol                #anonymous volume -- recommend not using this type
      environment:
        - bootstrap.memory_lock=true
      depends_on:
        - webapp_db                              #service name, not container name
        
volumes:
  db_data: /var/lib/mysql                        #volume_name: docker container file path
    #driver: local                               #this tells docker to store the files in a dir on the host
    #external: true                              #this tells docker that the volume was created via "docker volume create"
    # more info at https://docs.docker.com/compose/compose-file/compose-file-v3/#volume-configuration-reference

Dockerfile

# Instructions to build an IMAGE
# https://docs.docker.com/engine/reference/builder/

FROM python:3.7
LABEL "com.example.vendor"="ACME Incorporated"
LABEL com.example.label-with-value="foo"
LABEL version="1.0"
LABEL description="This text illustrates \
that label-values can span multiple lines."

ENV bootstrap.memory_lock=true \
    alias ls='ls -al'

WORKDIR /home/app                                        # mkdir -p /home/app & cd /home/app

COPY requirements.txt ./                                 # or "COPY . ." <- copy everything from current dir to WORKDIR

RUN pip install -r requirements.txt

EXPOSE 8050                                              # Port to use as default for image

CMD [“python”, “index.py”]                               # Command, Args to run when image starts up