Docker & Spring Boot

 My first upload to the containerized platform Goodbye to the server-based deployments. Feels good and well managed and can be distributed effortlessly.

When I executed my first http://localhost:9000/docker new journey to the containerization started.

Prerequisites

I downloaded Docker and installed it in my local machine and created a free account in docker hub (https://hub.docker.com/).

Log in to the docker with the docker hub credentials (Right-click on the docker desktop and click sign in)

Here goes my sample project set up

 pom.xml

Created a spring boot application using https://start.spring.io/ with spring-boot-starter-web dependency.

Created one controller to test the application

Controller class

The key part of the docker containerization is the creation of Docker file

note*: Where 'D' should be capital and no extension is required.

and the file content is 

FROM java:8 -> from java8 image

ADD target/springdocker.jar springdocker.jar -> our target jar naming 

ENTRYPOINT ["java","-jar","springdocker.jar"] ->to execute the jar

Just a 3 line of statements to make application live.👏

Login to docker with the credentials that registered while creating the account.

then I executed the command docker build -t sudeep1987dk/springdocker .

where sudeep1987dk is the dockerId, at the end. (dot) is mandatory if we are running from the same directory of the docker file which will include all the files to the container. 



All the 3 steps executed what we described in the Dockerfile.


To run this application hit the command like

docker run -p 9000:9000 sudeep1987dk/springdocker

first 9000 after -p (Port) is the docker port and the second 9000 is opening the port in the Operating System.


Tes the URL:http://localhost:9000/docker

  👍👍👍


Check the docker image by executing docker image ls


Finally pushing the docker image to the docker hub.

 docker image push sudeep1987dk/springdocker


And it is successfully pushed in the docker hub.


to stop docker once it is done execute the command: docker container stop $(docker container list -q)


Useful docker commands 


docker ps : will list running docker with container id 

docker ps -a  : will list all the docker images with history and current state

docker start 407751133d09: Start docker with docker id

docker stop 407751133d09: Stop docker with docker id

docker run : is an aggregate command (docker pull + docker start)

docker logs 407751133d09 : to get the logs or docker logs musing_lederberg  (instead of container id , the name also used to get the logs)

docker exec -it 407751133d09 /bin/bash : When that application is running it helps us to find the configuration and deployment directories 

docker container stop $(docker ps -a -q) : To stop all the live container.

docker rm $(docker ps -a -q) : To remove all the stopped containers.

Where '-it' opens an interactive terminal

exit is the command to exit from the  interactive terminal


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