springboot-docker-starterkit

Here I'll show how to deploy SpringBoot RESTful web service application with Docker and a communication between the containers.

Prerequisite

Installed: Docker, Java 1.8, Maven 3.x, Git

Steps

Clone source code from git

$ git clone https://github.com/exceptionalcode/springboot-docker-starterkit.git

Maven build source code
To build spring-boot-client/spring-boot-server cd inside the directory

$ mvn clean install

Build a Docker Image
To build an image go inside the spring-boot-client project directory on the location of Dockerfile

$ docker build -t spring-boot-client .

Note: If you run this command for first time it will take some time in order to download base image from DockerHub

Same for the spring-boot-server

$ docker build -t spring-boot-server .

(-t) represents the tag
(.) repesents the current directory for Dockerfile

Docker Images

$ docker images
REPOSITORY                           TAG                                              IMAGE ID            CREATED              SIZE
spring-boot-server                   latest                                           7026789d8203        12 seconds ago       121MB
spring-boot-client                   latest                                           fcba08ef1fb4        About a minute ago   121MB

With comamnd '$ docker images' you'll see two images build above

Run Docker Container

$ docker run --rm -d --name spring-boot-client -p 9001:9001 spring-boot-client

--rm stands for exited when the container is stopped or removed
-d to start a container in the backgroud
--name giving name to a container\ -p ports to map from container to ouside the world

Same with run the spring-boot-server container

$ docker run --rm -d --name spring-boot-server -p 9002:9002 spring-boot-server

Test the container
Client application endopoint

$ curl http://localhost:9001/

Output : Hello from client

Server application endpoint

$ curl http://localhost:9002/

Output : Hi!!!

Call Client to Server App
To call Server endpoint(Container) from Client endpoint(Container)

$ curl http://localhost:9001/callServerFromClient

Output : {"timestamp":"2020-06-06T14:50:56.717+00:00","status":500,"error":"Internal Server Error","message":"","path":"/callServerFromClient"}

Here you can observer you can not communicate from one container to other

Since both the container are running on two diffrent networks, we would require them to connect on the same netowork.

Create your own network\

$ docker network create --driver=bridge springbootnet

bridge is the network type and spring-boot-network is the name of a network

List Network

docker network ls

NETWORK ID          NAME                DRIVER              SCOPE
2894c742b8a8        bridge              bridge              local
9ddde2f74561        host                host                local
29e3be9c7b5d        none                null                local
ddc191b98c1a        springbootnet       bridge              local

Connect contnainer on the network

$ docker network connect springbootnet spring-boot-client
$ docker network connect springbootnet spring-boot-server

Inpect the network

$ docker inspect springbootnet

 "Containers": {
            "05d77b32de0c6d6e4862dec165d0bd96bbd6f055a6c1015cc68ecf98a2fe9cff": {
                "Name": "spring-boot-server",
                "EndpointID": "3a599a7220bc3782b9bfe03c2ab82bfa2f41bdb458955a0617e855ee181d2c84",
                "MacAddress": "02:42:ac:12:00:03",
                "IPv4Address": "172.18.0.3/16",
                "IPv6Address": ""
            },
            "66935f760ff8fee60745ec1617cf5ee24e1dbe5008da46bf92d296d0df14cbd9": {
                "Name": "spring-boot-client",
                "EndpointID": "7d3434989cabd1c23654f4e604aacf54e76041fae05d75d1f93a7751db1e7d23",
                "MacAddress": "02:42:ac:12:00:02",
                "IPv4Address": "172.18.0.2/16",
                "IPv6Address": ""
            }

Both the container are connected on the same springbootnet network

Test Communitcation
Endpoint client calling server :

$ curl http://localhost:9001/callServerFromClient

Output : Hello from server

Extra Commands

Stop Container

$ docker stop <containerId>

Remove Image

$ docker rmi <imageTagName>

Docker Compose

You can also run the container both the containers at once using docker compose./ Compose is a tool for defining and running multi-container Docker applications.

Create YML(docker-compose.yml)

version: '3.5'

services:
  spring-boot-client:
    container_name: spring-boot-client  
    image: spring-boot-client
    build:
      context: ./spring-boot-client/
      dockerfile: Dockerfile
    volumes:
      - /data/spring-boot-client
    ports:
      - "9001:9001"
    networks:
      - springbootnet
  spring-boot-server:
    container_name: spring-boot-server
    image: spring-boot-server
    build:
      context: ./spring-boot-server/
      dockerfile: Dockerfile
    volumes:
      - /data/spring-boot-server
    ports:
      - "9002:9002"
    networks:
      - springbootnet
networks:
  springbootnet:
    name: springbootnet
    driver: bridge

Compose Up

$ docker-compose up -d

By using the following command you can start up your application You can also run docker-compose in detached mode using -d flag

Compose stop

$ docker-compose stop

By using the following command you can stop up your application