In-Memory POP3 Server in C#

Background

Today I had a requirement where we needed to download a message from an email server via POP3 and convert it to another message format to be used in a CMS.

As anyone that knows me testing is very important so I wanted to find a way to create an in-memory POP3 server. The reason for this was I wanted a way to test different kinds of messages that needed to be saved in the CMS and not rely on an actual physical server. So after searching for a while I realised that there wasn't much out there so I decided to write my own.

Implementation

I created a gist that shows you the specs that I wrote. An example spec looks like this:



It("should get a message with OpenPop.NET", () =>
    {
        using (var client = new OpenPop.Pop3.Pop3Client()) {
            client.Connect("localhost", 110, false);
            client.Authenticate("test", "test");

            var message = client.GetMessage(1).ToMailMessage();
            message.From.Address.Should().Be("dzs@iname.com");
        }
    });



The email message that I used to test looks like the following:


Return-Path: <dzs@iname.com>
Received: from iname.com (localhost [127.0.0.1])
        by localhost.localdomain (8.8.5/8.8.5) with ESMTP id RAA01110
        for <dzs@localhost>; Sat, 3 Jan 1998 17:46:55 -0800
Sender: dzs@localhost.localdomain
Message-ID: <34AEEA0E.71EA3BCC@iname.com>
Date: Sat, 03 Jan 1998 17:46:55 -0800
From: Doug Steinwand <dzs@iname.com>
To: dzs@localhost.localdomain
Subject: Test Message

Here's the body of my test message

 - Doug

The actual implementation is in the following gist. The library that I chose to use was LumiSoft.Net as it already had an implementation of a POP3 server (it just needed to be extended).

The interesting part is that for some reason the library AE.Net.Mail (which was the one we wanted to use at work) does not work. I get the following error:


1) should get a message with AE.Net.Mail
   Failure/Error: System.IO.IOException: Unable to read data from the transport connection: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.


So I will probably be replacing it for one of the other client libraries.

This is a quick way to enable a POP3 server in memory and I hope this helps someone else in a similar position.

Web Development on Mono

Background

Today I decided that I wanted to try out deploying a ASP.NET MVC + Web Api application on Ubuntu.

Why do I want to do that? Well I have always loved C# and .NET, however I have never really enjoyed the Microsoft ecosystem. I am glad that Mono is around and have often wondered What if C# and .NET had targeted all platforms?

I wanted to get MVC 4 and Web API to work correctly. So after spending a few hours on it I thought I would share it with you all.

Process

Below will outline the steps that I took to get this working. I will leave the blood and tears to myself.

Preliminary

The first thing I did was to get vagrant to work. This makes it easier to provision a virtual machine on my mac book pro. The image that I used was Ubuntu Server 12.10 amd64 Minimal (VirtualBox 4.2.6). I created a Vagrantfile that contained the following code:


Vagrant.configure("2") do |config|
  config.vm.box = 'quantal64'
  config.vm.provision :shell, :path => 'bootstrap.sh'
  config.vm.network :forwarded_port, guest: 80, host: 9000
end

The bootstrap.sh contained the following:


#!/usr/bin/env bash

apt-get update
apt-get install -y git
apt-get install -y nginx
apt-get install -y g++
apt-get install -y gettext
apt-get install -y pkg-config
apt-get install -y automake

These packages will be used to build mono and the web-server  Once you have all this set up is just as easy as saying vagrant up and vagrant ssh

Compiling Mono

Once you have logged-in into the box you will run the following commands:

• wget http://download.mono-project.com/sources/mono/mono-3.0.7.tar.bz2
• tar -xvjpf mono-3.0.7.tar.bz2
• cd mono-3.0.7
• ./configure --prefix=/usr/local
• make
• sudo make install

Once all that finishes you will need to get web-sever to work:

• git clone https://github.com/mono/xsp
• cd xsp
• ./autogen.sh --prefix=/usr/local
• make 
• sudo make install

To test if it works create yourself a simple example project or use the one I made. To get the development web server up run sudo xsp4 --port 80 and go to http://localhost:9000/api/service/test. You should see the following:

<string xmlns="http://schemas.microsoft.com/2003/10/Serialization/">awesome</string>

Future

I will be going through some of the MVC 4 and Web API 4 features to make sure it all works. Once that is done I will try to do this on AWS by creating an AMI so that I can test some release processes. Thanks for reading and hope this was just as exciting for you as it was for me.

System.Spec - Specifications By Example in C#

System.Spec

I am a big fan of TDD and when I first started doing it I was accustomed to using NUnit in C#. Then I started learning Ruby and fell in love in how they were doing TDD/BDD. The gem they use is called RSpec.

For a while I was jealous that we did not have something as cool in C#. There is NSpec, however for me if did not read that well.

So I decided to create System.Spec. We are currently using at the place I work at and we are really enjoying it. As we continue dogfooding this solution we will build more features into it.

An example specification looks like the following:

namespace YourCompany.Specs
{
    using NSubstitute;
    using System.Spec;

    public class ImportantSpecification : Specification
    {
        protected override void Define()
        {
            Describe("A very cool specification", () => {
                It("should do something that is good", () => {
                    var testInterface = Substitute.For<ITestInterface>();
                    testInterface.Received().TestMethod();
                });
            });
        }
    }
}

As you can see there is some C# ceremonies that we need to take into consideration, Ruby allows for a much cleaner syntax. It follows closely the design of Jasmine.

Moving Forward

The following is what I plan doing in the coming weeks/months:

1. Add a runner for ReSharper
2. Add a runner for VS 2010
3. Add a runner for Xamarin Studio (if possible)
4. Allow reordering of tests.

I urge you to look at the solution and if you have any thoughts or enhancements just yell out.

Xamarin Studio - C# Development just got better

Today is a glorious day for all C# developers that have been looking for a way to get away from windows as their development environment.

In my email today I got a lovely surprise:

Hi!

Xamarin has today announced Xamarin Studio, an evolution of the MonoDevelop IDE with tons of improvements. All the new code has been merged into the MonoDevelop repository and will be the foundation for future MonoDevelop and Xamarin Studio releases. If you want to try the new MonoDevelop/Xamarin Studio you can get installers for Mac and Windows from the MonoDevelop download page.

Enjoy!

Lluis.

I urge you all to give it a try. Here are some instructions so that you don't make the same mistake I made:

1. Download the latest mono for OSX. This is version 2.10.11
2. Download Xamarin Studios from here.
3. Install them both and fire up Xamarin Studios

Enjoy your C# development.