/DiveIntoDocker

In this repository, you'll find a curated collection of tutorials, code samples, and resources designed to learn Docker.

Primary LanguageJavaScript

Docker Commands

To build an image

docker build .

To build an image with a tag name

docker build -t "image-name" .

To list all the images

docker images ls

To delete an image

docker image rm image-name

To run a container with -d detach mode and port forwarding

docker run -p 3000:3000 -d  image-name

To run a container with a custom container name

docker run -p 3000:3000 -d --name container-name  image-name

This command will list the running container in our system.

docker ps

This command will return the list of all Started or Stopped containers

docker ps -a

This cmd will give us a interactive bash for our container

docker exec -it container-name bash

To kill a running container

docker rm container-name -f

To kill a running container and delete the associate volume with it.

docker rm container-name -fv

To sync you current folder dir with the docker container /app dir use the below commands.

docker run -v %cd%:/app -p 3000:3000 -d --name container-name image-name

This command help us to get the logs of the container

docker logs containerID / container-name

Anonymous volume this hack for node_modules folder

docker run -v %cd%:/app -v /app/node_modules -p 3000:3000 -d --name container-name image-name

Docker Read Only Bind Mount

docker run -v %cd%:/app:ro -v /app/node_modules -p 3000:3000 -d --name container-name image-name

How to pass ENV variable at run time

docker run -v %cd%:/app:ro -v /app/node_modules --env PORT=4000 -p 3000:4000 -d --name node-app  node-app-image

How to pass ENV file at run time

docker run -v %cd%:/app:ro -v /app/node_modules --env-file ./.env -p 3000:4000 -d --name node-app  node-app-image

Docker volumes

docker volume ls

How to remove docker volumes

docker volume rm volume_id

How to remove docker unused volumes

docker volume prune

How to run docker compose file

docker-compose up

How to run docker compose file in detach mode

docker-compose up -d

How to down a container with docker compose

docker-compose down

How to down a container with docker compose with that delete anonymous volume

docker-compose down -v

How to build a container with docker compose after a change

docker-compose up -d --build

How to build a container with docker compose after a change

docker-compose -f docker-compose.yml -f docker-compose.dev.yml up

How to get list of all networks

docker network ls

How to inspect a network

docker inspect container-name

How to run a specific service/container without running its dependencies

docker-compose -f docker-compose.yml -f docker-compose.dev.yml up -d --no-deps service-name

How to scale a service

docker-compose -f docker-compose.yml -f docker-compose.dev.yml up -d -scale node-app=2

How to follow logs

docker logs 28docker-node_and_express-node-app-1 -f

Key Takeaways on PORT Forwarding

  • By Default Docker container can talk to the outside world.

  • But from the outside world no once can talk with our container that is by default due to security mechanism.

  • Outside world means local machine and internet both.

  • docker run -p 3000:3000 -d  image-name Here in this command do port forwarding we send the traffic which comes to our machine at port 3000 will be forwarded to container port 3000.

  • Now we are able to talk to our container.

  • number of left to -p is the traffic coming from outside world and the number on right side is the number which our container is expecting.

Key Takeaways on Sync Source code

  • In docker we can sync our source code with the docker work dir.
  • So we don't have to rebuild our image again as we make changes in our code.
  • During build command ve need use -v flag with localPath:ContainerPath
  • Here we have use %cd% which automatically fetch the current local path of pour folder.
  • /app is the path to folder on container from which we have to sync.
  • This -v is bind mount.
  • This will sync all the folder.

Key Takeaways on anonymous volume

  • To prevent the local folder from over riding the /app dir of our container we use anonymous volume.
  • Using another v flag we can mention the anonymous volume.
  • -v /app/node_modules this is little hack to bind the node_modules folder with our container.
  • All the folder will get sync but it will not touch the node_modules folder of container

Key Takeaways Read Only Bind Mount

  • -v %cd%:/app:ro using this command we cannot create file or folder in container from container.
  • This is good for security reasons as we don't want that some one change our source code from our local dir.

Key Takeaways on Volumes that build during spinning up a container

  • The volume which is listed from running the docker volume ls command is the anonymous volume that is created while building up the container.
  • docker run -v %cd%:/app:ro -v /app/node_modules --env-file ./.env -p 3000:4000 -d --name container-name image-name
  • Here the node_modules folder is preserved us for every time by the docker and that's why the volume is created by the docker.
  • We can delete them by running docker volume rm volume_id
  • Another command is docker volume prune this will delete the volume which is not in use.

Key Takeaways on Docker Compose

  • Docker compose actually helps to run the command.
  • We have to create a file in which each step and configuration is mentioned.
  • Then just run that file.
  • In docker-compose file we have to first mentioned the docker compose version which we are using it.
  • Each container in docker-compose file refer as service.
  • Docker compose looks for image project_dir-name-of-services.
  • Docker compose is not smart we need to tell him when we ant to build it again
  • Read documentation for docker compose file.
  • In docker compose file when we use a another image then we can use a image property.

Key Takeaways on Volumes

  • Bind Mount Syncs data with your folder local drive 👉 ./:/app:ro
  • Anonymous volume 👉 /app/node_modules
  • Named Volume is same as Anonymous volume only we gave a name 👉 mongo-db:/data/db
  • We need to declare our named volume in docker-compose file so that another services can also used that volume.

Key Takeaways on Networks

  • Bridge and host network comes up with the docker.
  • As there is custom networks so we have DNS.
  • We can talk to other docker container with the help of DNS.
  • If we want that our one container talk to our another container just refer to use service name DNS will resolve it get its IP for us.
  • Only applicable to network we create.

Key Takeaways on depends-on property

  • depends on actually helps to spin up the mentioned container first.
  • Like we want our mongo container to spin up before the node container so in this case depends on property will help us out.

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