Simple docker Project

Task:

Create a Dockerfile for a simple web application (e.g. a Node.js or Python app)

Steps:

1. Launch AWS ubuntu ec2 instance.

2. Open the security group of the instance and add a new inbound rule to allow all the IP addresses and ports to access the application.

   

   1. Install docker

      ⦿ Manual installation: Docker can be installed by following the instructions over here : Manual instructions

      ⦿ script-based installation: Script
      Run the below two comments:
      curl -fsSL get.docker.com -o get-docker.sh
      or wget -O get-docker.sh https://get.docker.dom

      sh get-docker.sh

      

      1. Docker allows communication to the Unix socket for the users who belong to the docker group. so let's add the current user to the docker group sudo usermod -aG docker <username>. Then logout and login.

         

         1. Clone the repository from Github to ubuntu server using below command:

            git clone <Repo_URL>

            

            1. Create a docker file

               vim Dockerfile

            2. The specific commands you can use in a dockerfile are:

               • FROM: The first thing we need to do is define from which image we want to build from. Creates a layer for Jar file

               • Next we create a directory to hold the application code inside the image, this will be the working directory for your application. WORKDIR a command is used to define the working directory of a Docker container at any given time.

               • COPY is a dockerfile command that copies files from a local source location to a destination in the Docker container.

               • RUN command to execute the command SPC and Builds your container

               • EXPOSE instruction informs Docker that the container listens on the specified network ports at runtime.

               • CMD Specifies what command we want to run when our image is run inside of a container.

                 To build an image using Dockerfile, Go to the directory that has your Dockerfile and run the following command:

                 docker build -t <image-name> .

                 

            3. Build the image using the Dockerfile and run the container

               Image created, now can create container using command-

               docker run -d - -name <container-name> -p <image-name>

               Running your image with -d runs the container in detached mode, leaving the container running in the background. The -p flag redirects a public port to a private port inside the container and - - name flag for assigning name to docker container.

               

               Command to delete all running containers forcefully : docker container rm -f $(docker container ls -q )

            4. Once the container is created run the application in the laptop

               

               1. Push the image to a public or private repository (e.g. Docker Hub )

Use command “docker login” to login to dockerhub.

Push docker image to docker hub using command:

• docker push <image-name>