Docker Node

Build Image

docker build .

alpine version in docker means the image is smallest possible to run basic functions

To build image from custom file

run docker build -f Dockerfile.dev .

• -f tells we are using a custom file.
• . the dot at the end means the build context(current directory)

Copy Command

Copy path-to-local-file-system path-to-copy-stuff-in-container eg - COPY ./ ./ will copy everything from current directory to container

To tag Image

docker build -t <dockerId>/<imageName> . eg docker build -t chetan/nodeApp . To run the tag image docker run chetan/nodeApp

Port mapping

docker run -p incomingPort : containerPort imageId example docker run -p 8080 : 8080 chetan/nodeapp

To start the image in interactive mode

docker run -it chetan/nodeapp

To override the default command with image name, while starting a image

docker run -it chetan/nodeapp <command we need to run> eg docker run -it chetan/nodeapp sh

To run command in running container with container Id

docker exec -it <containerId> <command we need to run> eg docker exec -it 21212121 sh

Working directory

WORKDIR <folder> any command will run relative to this path in container eg WORKDIR /user/app

To see running containers

docker ps

IF React App Exits Immediately with Docker Run Command

run docker run -it -p 3000:3000 IMAGE_ID

Create Docker Volumes to map folders for live reloads

Copy command creates a snapshot of the folders in the container, while volumes creates references.

run docker run -p 3000:3000 -v /app/node_modules -v ${pwd}:/app <image_id> The above command says except node_module, reference everything inside container to the current directory.

Docker Compose

To make networking between container easy.

to run image

docker-compose up

to build and run an image

docker-compose up --build

To start container in background

to start docker-compose up -d to stop docker-compose down

To run docker compose container in interactive mode

add stdin_open: true # docker run -i add tty: true # docker run -t

To map volumes for reload

 volumes: 
    - /app/node_modules    -> this says don't map node modules, use it from the container
    - .:/app    ---> this says map all content in current folder to conetnt under /app

To run test in a running container

get the Id of the running container, we started with docker-compose up to attach and run test run docker exec -it <container-id> npm run test this is make the test live reload on any changes