Multistage Dockerfiles

Building the technology specific packages also can be done as part of docker image building using multi stage Docker builds
structure

FROM <image> as stage1
...
...
...


FROM <image> as stage2
...
...
...

FROM <image> as stage3
...
...
...

Refer Here for official docs
Lets build spring pet clinic (maven, jdk 17, spring boot) Refer Here for code
Manual steps to build the application

# ensure jdk 17 is installed
# ensure maven is installed

Multistage dockerfile

FROM maven:3-amazoncorretto-17 AS build
ADD . /springpetclinic
WORKDIR /springpetclinic
RUN mvn package


FROM amazoncorretto:17-alpine-jdk
COPY --from=build /springpetclinic/target/spring-petclinic-3.2.0-SNAPSHOT.jar /spring-petclinic-3.2.0-SNAPSHOT.jar
EXPOSE 8080
# make this non root
CMD [ "java", "-jar", "/spring-petclinic-3.2.0-SNAPSHOT.jar" ]

Build the image and scan the image using trivy scanner
Installation Refer Here
Multistage dockerfile for nop commerce

FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build

WORKDIR /src                                                                    
COPY ./src ./

# restore solution
RUN dotnet restore NopCommerce.sln

WORKDIR /src/Presentation/Nop.Web   

# build project   
RUN dotnet build Nop.Web.csproj -c Release

# build plugins
WORKDIR /src/Plugins/Nop.Plugin.DiscountRules.CustomerRoles
RUN dotnet build Nop.Plugin.DiscountRules.CustomerRoles.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.ExchangeRate.EcbExchange
RUN dotnet build Nop.Plugin.ExchangeRate.EcbExchange.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.ExternalAuth.Facebook
RUN dotnet build Nop.Plugin.ExternalAuth.Facebook.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Misc.Brevo
RUN dotnet build Nop.Plugin.Misc.Brevo.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Misc.WebApi.Frontend
RUN dotnet build Nop.Plugin.Misc.WebApi.Frontend.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Misc.Zettle
RUN dotnet build Nop.Plugin.Misc.Zettle.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.MultiFactorAuth.GoogleAuthenticator
RUN dotnet build Nop.Plugin.MultiFactorAuth.GoogleAuthenticator.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Payments.CheckMoneyOrder
RUN dotnet build Nop.Plugin.Payments.CheckMoneyOrder.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Payments.CyberSource
RUN dotnet build Nop.Plugin.Payments.CyberSource.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Payments.Manual
RUN dotnet build Nop.Plugin.Payments.Manual.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Payments.PayPalCommerce
RUN dotnet build Nop.Plugin.Payments.PayPalCommerce.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Pickup.PickupInStore
RUN dotnet build Nop.Plugin.Pickup.PickupInStore.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Shipping.FixedByWeightByTotal
RUN dotnet build Nop.Plugin.Shipping.FixedByWeightByTotal.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Shipping.UPS
RUN dotnet build Nop.Plugin.Shipping.UPS.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Tax.Avalara
RUN dotnet build Nop.Plugin.Tax.Avalara.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Tax.FixedOrByCountryStateZip
RUN dotnet build Nop.Plugin.Tax.FixedOrByCountryStateZip.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Widgets.FacebookPixel
RUN dotnet build Nop.Plugin.Widgets.FacebookPixel.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Widgets.GoogleAnalytics
RUN dotnet build Nop.Plugin.Widgets.GoogleAnalytics.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Widgets.NivoSlider
RUN dotnet build Nop.Plugin.Widgets.NivoSlider.csproj -c Release
WORKDIR /src/Plugins/Nop.Plugin.Widgets.What3words
RUN dotnet build Nop.Plugin.Widgets.What3words.csproj -c Release

# publish project
WORKDIR /src/Presentation/Nop.Web   
RUN dotnet publish Nop.Web.csproj -c Release -o /app/published

WORKDIR /app/published

RUN mkdir logs
RUN mkdir bin


FROM mcr.microsoft.com/dotnet/aspnet:8.0
EXPOSE 5000
COPY --from=build /app/published /app
WORKDIR /app
CMD ["dotnet", "run","Nop.Web.dll", "--urls", "http://0.0.0.0:5000"]

Break till 8:05

Docker Registries

Docker Registries can store docker images which can be shared.
The default docker registry is docker hub
To push the images to docker hub

# login into dockerhub
docker login

* In Dockerhub we have two types of repositories
* private
* public
* To create a repository generally the naming convention is <username>/<repo-name>:<image-tag>

* Let push the image docker image push <image-name>

Generally enterprises use private docker registries, There are many providers
- DockerHub Paid account
- AWS Elastic Container registry
- Azure Container Registry
- Google Container Registry
- jfrog