Creating an F# ASP .Net Core application (Part 1)

So, at the office we are having an onsite training provided by u2u this week. We are supposed to be learning Advance Web development with ASP .Net. This means that I have been doing a lot of small applications in C# using .Net Core and wondering how hard could it be to write the same example applications in F#.

It seems to be harder and uglier than I expected. I am not sure if anybody else is interested in building an F# ASP .Net Core application but I have already started and lets better document my path.

Of course Visual Studio has some support for F# but, as the time of this writting, there is no template installed by default to start a new F# project in .Net Core, so I decided to do everything using VS Code, Ionide and the dotnet-cli. God Bless me.

You can start by executing dotnet new -l fs. Where the -l option allows you to select the language. For F# the valid options are fs, f# and fsharp.

This command will create two files that will allow us to build a Hello World console application and will give a fundation to create the ASP .Net Core application.

Program.fs

open System

[<EntryPoint>]
let main argv = 
    printfn "Hello World!"
    0 // return an integer exit code

project.json

{
  "version": "1.0.0-*",
  "buildOptions": {
    "debugType": "portable",
    "emitEntryPoint": true,
    "compilerName": "fsc",
    "compile": {
      "includeFiles": [
        "Program.fs"
      ]
    }
  },
  "tools": {
    "dotnet-compile-fsc":"1.0.0-preview2-*"
  },
  "frameworks": {
    "netcoreapp1.0": {
      "dependencies": {
        "Microsoft.NETCore.App": {
          "type": "platform",
          "version": "1.0.1"
        },
        "Microsoft.FSharp.Core.netcore": "1.0.0-alpha-160629"
      }
    }
  }
}

Executing dotnet restore will restore the packages. Executing dotnet build will build the project. Executing dotnet run will run the application and it will print to console

Hello World!

Actually, executing dotnet run will also execute build if there are changes not build yet.

The second part of this series is here.