Just for fun, earlier today one of my colleagues asked if I could try and make a tiny-footprint WebAPI that echoed requests using ASP.NET Core. I was able to get the WebAPI done in about 70 lines of code. All thanks to ASP.NET Core being amazing! So, this is what I ended up with so far.

The Code

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Newtonsoft.Json;
using System;
using System.Linq;

namespace TinyWebApi
{
    class Program
    {
        static readonly IWebHost _host;
        static readonly string[] _urls = { "http://localhost:80" };

        static Program()
        {
            IConfiguration _configuration = new ConfigurationBuilder()
                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
                .Build();
            _host = BuildHost(new WebHostBuilder(), _configuration, _urls);
        }

        static void Main(string[] args)
        {
            _host.Run();
        }

        static IWebHost BuildHost(
            IWebHostBuilder builder, IConfiguration configuration, params string[] urls)
        {
            return builder
                .UseKestrel(options =>
                {
                    options.NoDelay = true;
                })
                .UseConfiguration(configuration)
                .UseUrls(urls)
                .Configure(app =>
                {
                    app.Map("/echo", EchoHandler);
                })
                .Build();
        }

        static void EchoHandler(IApplicationBuilder app)
        {
            app.Run(async context =>
            {
                await context.Response.WriteAsync(
                    JsonConvert.SerializeObject(new
                    {
                        StatusCode = (string)context.Response.StatusCode.ToString(),
                        PathBase = (string)context.Request.PathBase.Value.Trim('/'),
                        Path = (string)context.Request.Path.Value.Trim('/'),
                        Method = (string)context.Request.Method,
                        Scheme = (string)context.Request.Scheme,
                        ContentType = (string)context.Request.ContentType,
                        ContentLength = (long?)context.Request.ContentLength,
                        QueryString = (string)context.Request.QueryString.ToString(),
                        Query = context.Request.Query
                            .ToDictionary(
                                _ => _.Key,
                                _ => _.Value,
                                StringComparer.OrdinalIgnoreCase)
                    })
                );
            });
        }
    }
}

(The code above works as expected, and it's not broken.)

The WebAPI

The WebAPI is supposed to echo back the request with a JSON.

Example Request

http://localhost/echo?q=foo&q=bar

Example Response

{
  "StatusCode": "200",
  "PathBase": "echo",
  "Path": "",
  "Method": "GET",
  "Scheme": "http",
  "ContentType": null,
  "ContentLength": null,
  "QueryString": "?q=foo&q=bar",
  "Query": {
    "q": [
      "foo",
      "bar"
    ]
  }
}

My Problem

I blew my colleague away with just the 70+ lines of code to do the job, but then when we took a look at the file size it wasn't as impressive...

At the moment with all these dependencies, my WebAPI is compiling to 54.3MB.

I am stuck with trying to figure out how to reduce the disk footprint of this project. The packages I have installed are bundled up with so much stuff we don't really need and I keep running into trouble trying to find out the best resource or method to removing the unneeded references for this project.

The .csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp1.1</TargetFramework>
    <RuntimeIdentifier>win7-x64</RuntimeIdentifier>
    <ApplicationIcon>Icon.ico</ApplicationIcon>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore" Version="1.1.2" />
    <PackageReference Include="Microsoft.AspNetCore.Hosting.Abstractions" Version="1.1.2" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc.Core" Version="1.1.3" />
    <PackageReference Include="Microsoft.AspNetCore.Server.Kestrel" Version="1.1.2" />
    <PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" Version="1.1.2" />
    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="1.1.2" />
    <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="1.1.2" />
    <PackageReference Include="Newtonsoft.Json" Version="10.0.2" />
  </ItemGroup>

</Project>

Is there any quick way for me to know what references my project needs based on the code provided? I started earlier by wiping clear all the above dependencies and then trying to add them one by one, but it turns out to become a never ending headache of trying to solve missing references and it seems to take forever to solve. I'm sure someone out there has a solution for something like this, but I can't seem to find it. Thanks.