dockerGetStarted.md

Commands to run docker

some basic commands might not run windows

docker --version
whoami
uanme

To list all the docker containers

docker container ls

To stop docker

docker stop dockerId

To remove the docker container

docker container rm dockerId

To remove the docker container forcefully

docker container rm -f dockerId

To list all the docker images

docker image ls or docker image

To remove the docker image

docker image rm imageId

Command to start a docker

docker start containerName

Command to start a interactive bash when docker starts

docker exec -it containerName bash

To run ubuntu on docker please remind docker is aslo a kind of virtual machine

docker run -it ubuntu -it === interactive gonna interact with the ubuntu machine docker run -d ubuntu -d == deatached mode

If only want to pull the image not want to use it

docker pull node

now we can interact with the node image

docker run -it node

To rename the dockerfile

docker tag nikhil791/myapp nikhil791/rename

Lets make a simple docker image

1. make a simpel node server

npm init -y
npm i express

2. make a simple express app

const express = require('express')
const app = express()
const port = 9000

app.get('/', (req, res) => {
  res.json(message:'I am inside docker container')
})

app.listen(port, () => {
  console.log(`Server is running on port ${port}`)
})

3. In order to make a docker image make a docker file naming "Dockerfile"

FROM node:latest

COPY index.js /home/app/index.js
COPY package.json /home/app/package.json

WORKDIR /home/app

RUN npm install

EXPOSE 9000

CMD [ "node", "index" ]

To build images

docker build -t myapp . or the file location

again to run docker

docker run -it myapp

To check whether the container is running status

docker ps but it will not work as you have exposed the 9000 port inside the docker machine and also you have exposed that port to the external world but have not mapped it to main machine

Port mapping (publishing ports) can only be done when creating a new container, not with existing containers.

Mapping the port or Port mapping p stand for port

docker run -p 3000:9000 myapp

• here if we don't write the EXPOSE 9000 in the Dockerfile the servers 9000 port will be still accessible because of the run -p command

Koi bhi web service chalani ho to we have to port mapping eg nginx 8080:80 apache etc

docker run -it --name nx -p 8080:80 nginx

if want to use the machine with running

docker run -it -p 3000:9000 myapp

if there are to many file there you are not going to copy all of them one by one

COPY index.js /home/app/index.js
COPY package.json /home/app/package.json
instead of this use
COPY . /home/app
it will copy all the file also the node modules to avoid this

make a .dockerignore file and add node_modules/

Pushing images on dockerhub

docker build -t username/image_name . or the file location

• it is the naming convention and every idiot should follow it docker push username/image_name

app.run(debug=True,host="0.0.0.0", port=5000)

with host we can access this app from any device from same network

app.run(debug=True, port=5000)

it will only bind to localhost so the server will not accessble from the outside whether you exposet the 5000 port or not