Unit testing MongoDB in C# part 4: the tests, finally

More than a year. Wow, that’s a lot, even for me! In the last episode of this series we discussed about how to create the Factories for our Repositories. I guess now it’s time to put an use to all those interfaces and finally see how to unit test our MongoDB repositories ūüôā

Remember: we are not testing the driver here. The MongoDB team is responsible for that. Not us. 

What we have to do instead is to make sure all our classes follow the SOLID principles and are testable. This way we can create a fake implementation of the low level data access layer and inject it in the classes we have to test. Stop.

Let’s have a look at the code:

In our little example here I am testing a CQRS Command Handler, the one responsible for creating a user. Our handler has an IDbContext as dependency, which being an interface allows us to use the Moq Nuget package to create a fake context implementation. 

Also, we have to instruct the mockDbContext instance to return a mock User Repository every time we access the .Users property.

At this point all we have to do is to create the sut, execute the method we want to test and Verify() our expectations. 

Let’s make a more interesting example now:

Now that we have created the user, we may want also to update some of his details. The idea here is to instruct the mockRepo instance to return a specific user every time the FinstOneAsync method is executed.

Again, now we just need to verify the expectations and we’re done!

Note that in this case we are making an assumption about the inner mechanism of the Handle() method of the UpdateUserHandler class. Personally I tend to stick with Black Box Testing, but sometimes (eg. now) you might be forced to use White Box Testing instead. If you don’t know what I am talking about, there’s a nice article here you may want to read.


Yet another “How to use SASS with WordPress” guide

Yes, it’s another one. If you lookup on Google there are are tons of articles about how to use SASS in a WordPress theme, so why writing another one?

Well, the answer is simple. Because I can. Because I am bored. Because I’m going to give you the sources with no fuss.

First of all, take a look at this repo.

As you can easily notice, it contains part of the standard WordPress folder structure and a bunch of other files. And trust me, I am not that kind of guy who adds files for nothing.

The main idea here is to have Gulp search and watch for our .scss files in the child theme folder and build the final style.css files every time something changes. Nice isn’t it?

Before we start we need of course to install some dependencies. Fire up the Terminal and run:

sudo npm install -g gulp

just to make sure we have Gulp installed globally (that’s why you need sudo for that). Then run:

npm install gulp gulp-sass gulp-clean gulp-autoprefixer –save-dev

 We’ll discuss about those packages later.

I have added a “sass” folder inside “twentysixteen-child” that contains all our SASS files.

The style.scss file is our main entry point and as you can see from the repo, contains all the boilerplate code required by WordPress to discover the child theme.

I tend to include a _base.scss file that contains all the basic dependencies like variables and mixins. Then in style.scss I append all the page templates, like _home.scss in our small example.




Now let’s talk about the Gulp configuration file. The first lines contain the dependencies we need in our tasks, gulp, sass, clean and autoprefixer (more on this later).

Then we have the paths we want our SASS compiler to run on. As you can see I am using the child theme path as a base concatenated to the others.

After this we can start with the tasks. The first one is responsible of removing all the files from the previous build (basically just one, style.css ).

Then we have the actual SASS compilation. I am passing to the sass() function an empty configuration object, but there are several options available, for example you may want to compress the result.

The “postprocess” task is responsible of every post-compilation step we may want to perform on the output css file. In our case, I am using a very useful library named Autoprefixer that adds all the vendor-specific prefixes. If you’re interested, there’s a nice article on CSS-tricks.com, you can read it here.

The last bit is the “watch” task. This is interesting: basically it tells Gulp to monitor our /sass/ folder and every time there’s a change, to run again the “build” task. That’s it!

Now all you have to do, if you’re using Visual Studio Code like me, is to hit cmd+shift+p  and type “Configure Task Runner”:

then pick Gulp as your default Task Runner. If you take a look at the tasks.json file in the repo, you will notice that I have added some more custom configuration just to instruct VS Code to use the “default” task as main entrypoint.

That’s it!

How I almost lost all my source codes.

Now sit down my dear and listen carefully, I’ll tell you a story about how I almost lost all my sources.
A while ago, I decided to give my marvelous Macbook pro mid-2013 an upgrade. I searched online a little bit and at the end I bought an SSD drive, a Corsair Force LE 240GB

“But 240 is not enough!” you might say.  “You’re right”. It’s not enough. 

I was not using the DVD drive at all so after a brief research, I found the right adapter and replaced it with the old 500gb Apple disk , leaving space for my shiny new SSD.

Everything was perfect, El Capitan was lightning fast, everybody was happy. But then came the day that I needed Windows. So Bootcamp joined us and new partitions started to appear.

180GB OSX Extended and 60GB NTFS on the SSD.
450GB OSX Extended and 50GB exFAT on the ol’ Apple disk.

Again, everything was perfect, El Capitan was still lightning fast, Windows 10 was running fine, everybody was happy.

I was running Windows from the SSD and all the programs were installed on the other drive, together with all the source codes. Yes, before you ask, I have a Bitbucket account. Yeah, a Github one too, but Bitbucket gives you private repos for free.

However, after a while, I realized that when Win10 goes to sleep mode some strange misbehavior appears, in the form of weird SMART messages when turning on MacOs.

Long story short, one day I rebooted from Win to MacOs and puff! the partition with all the sources was gone. Disappeared. An empty, dark and cold space.
I almost got an heart attack.

Disk Util, Disk Warrior, mysterious command line tools, I tried everything, nothing worked. After hours of researches and curses, I fired up Windows and did the only thing I had left:

chkdsk e: /f

That saved my day.

Moral of the story? Always backup your source codes, even the most insignificant snippets.


I married a wonderful woman.

The fact that she’s my high school crush just makes everything more magical.

To be honest, sometimes I feel like I am in a tv show for teens, like Dawson’s Creek or Beverly Hills 90210…

And now I am sitting here, in the house we are still decorating together, while¬†she’s¬†taking care of¬†me ( I got high fever the day after the wedding ) and our pregnant cat meowing at us.

I love you, iLa.


Edge Guardian available on Steam!

This time I just want to spread the word about my two good friends Maurizio and Marco from Hypotermic Games, who have finally got the chance to publish their first game on Steam, Edge Guardian !

In a nutshell, it’s an action beat-em-up for the HTC Vive¬†where you’ll find yourself in a cube-based world, forced to punch¬†your way out through thousands of enemies.

I don’t own an HTC Vive, but even if I haven’t had the possibility to try the game, I can easily say that it’s gonna be really addictive.¬†Take a look at the gameplay if you don’t trust me.

Good luck guys!

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