Docker Image

[StefanGreve]

Task

Containerize this backend with a docker image for deployment on Linux.

• create docker image and expose port 5000 over HTTP
• add a docker-compose.yml file for configuring redis and postgresql
• also expose port 5001 over HTTPS and use a certificate

Further Reading:

• https://learn.microsoft.com/en-us/dotnet/architecture/containerized-lifecycle/design-develop-containerized-apps/build-aspnet-core-applications-linux-containers-aks-kubernetes
• https://github.com/tumugin/lullaby/tree/main

Note:

Starting with .NET 7, it's also possible to creative a container without using explicitly docker:

• https://www.youtube.com/watch?v=3s-RfwvijpY

However, in this project we will keep using plain old docker files for the time being.

[StefanGreve]

Local Requirements

(For the following prerequisites, see also: https://docs.docker.com/desktop/install/windows-install/)

• check if virtualization is enabled:

Get-ComputerInfo -Property "HyperV*" | select -ExpandProperty HyperVRequirementVMMonitorModeExtensions

• install docker

winget install --id docker.dockerdesktop

• install Windows Subsystem for Linux (WSL)

wsl --install

[StefanGreve]

First Attempt

First draft of a Dockerfile:

FROM mcr.microsoft.com/dotnet/sdk:7.0 AS build-environment
ARG project=AdvancedSystems.Backend
WORKDIR /src
COPY . .

# build
RUN dotnet restore $project/$project.csproj --configfile $project/nuget.config --verbosity minimal

# publish
RUN dotnet publish $project/$project.csproj --configuration Release --output /Release --no-restore --nologo

# serve
FROM mcr.microsoft.com/dotnet/sdk:7.0
WORKDIR /Release
COPY --from=build-environment /Release ./
EXPOSE 5001
ENTRYPOINT ["dotnet", "AdvancedSystems.Backend.dll"]

Then build the container with:

docker build --rm -t adv-sys/backend:latest .

Next start the image:

docker run --rm -p 5001:5001 -e ASPNETCORE_HTTP_PORT=https://+:5001 -e ASPNETCORE_URLS=https://+:5001 adv-sys/backend

Exception Message

The command above currently throws the following exception:

Unhandled exception. [ERR] 20:58:08.3267 - The application was forced to shut down because an unknown error occurred
System.InvalidOperationException: Unable to configure HTTPS endpoint. No server certificate was specified, and the default developer certificate could not be found or is out of date.

Further Reading:

• How to setup the dev certificate when using Docker in development dotnet/AspNetCore.Docs#6199 (comment)