Dockerizing your apps

Building Docker Images

app

Approaches

Imperative

registry

1. pull image

2. run container 

3. copy source code 

4. build/compile

5. commit

6. push

Steps

dockerfile

FROM

RUN

COPY

EXPOSE

CMD

dockerfile

FROM

RUN

COPY

EXPOSE

CMD

docker build

http://hub.docker.com

sign up

Building Image for

PetClinic App

• Spring boot application

• Uses HSQLDB / MySQL as DB backend

https://github.com/devopsdemoapps/spring-petclinic

Two Step Process

• Build step

• Package Step

registry

host

build step

registry

host

package step

registry

selecting base image

lab

https://gist.github.com/initcron/61046646e5afcd1f0cb7fef9eebe2b75

Image creation instructions (Manual)

Dockerfile

Dockerfile

FROM java:8-jre-alpine

WORKDIR /

COPY target/spring-petclinic-*.jar app

EXPOSE 8080 

CMD java -jar app 

https://gist.github.com/initcron/f6056e6045ecbf908d2a1b321b2b1c41

build

docker image build -t <dockrhub user id>/petclinic:v2 .

docker image ls 

dot (current directory)

test image

docker container run -idt --name pc <dockrhub user id>/petclinic:v2

docker container ls 

docker logs pc

tag as latest

docker image tag  <dockrhub user id>/petclinic:v2  <dockrhub user id>/petclinic:latest

docker image ls 

publish image to registry

docker image push <dockrhub user id>/petclinic:latest

docker image push <dockrhub user id>/petclinic