Publishing a ASP.NET Core App in Fly.io.

Note: I discovered this while working (work in progress) on a more complex declarative web app framework using html/json which i am using fly.io to deploy guiapp app for publishing static data webapps in Git Repositories

Note : Docker is not required and hence can be done in Windows under Parallels in macos for those who don't have nested virtualization enabled/not available.

Create a Demo Asp.Net Core Mvc Project in an Empty Directory

    dotnet new mvc -o AspNetDemo
    code -r AspNetDemo

Modify the Asp.NET core Project to add the following property

    <ServerGarbageCollection>false</ServerGarbageCollection>;

The above setting will reduce the memory used by Asp.NET core so that the app can be deployed in the free tier of fly.io service

Move to the Asp.Net Core Project Directory and run the following publish command to generate a

    dotnet publish -r linux-musl-x64 --output "..\linux64_musl" --self-contained true -p:PublishSingleFile=true -p:PublishTrimmed=true

    FROM mcr.microsoft.com/dotnet/runtime-deps:6.0-alpine-amd64

    EXPOSE 8080

    RUN mkdir /app
    WORKDIR /app
    COPY ./linux64_musl/. ./

    RUN chmod +x ./AspNetDemo
    CMD ["./AspNetDemo", "--urls", "http://0.0.0.0:8080"]

Ensure that you have installed fly.io client and done the getting started guide in Fly.IO Getting Started

Step 6 - Deploy AspNetDemo app to fly.io

Deploy the AspNetDemo app to fly.io using below commands. Ensure that the commands are run in the directory where the docker image exists

    flyctl launch

Enter the AppName : aspnet1

Select the Organization : Personal

Select the Region : Singapore

Step 7 - Verify the deployment

Verify the deployment by opening the browser and entering the following url in the following format

    https://aspnet1.fly.dev