Versioning to an Asp.Net Core Web API

There are occasions you would like or need to add versioning to your API in order to specify availability or non-availability of functionality.

There are a few options available to such as Query String, Url based as well as Http header.

For my purposes I am going to talk about the Url based approach, as I have implemented this option in my MyReverie repo due to a matter of preference of being cleaner and more explicit.

First things first we will need to go ahead and install the Nuget package:

  • Microsoft.AspNetCore.Mvc.Versioning

Within the Startup class ConfigureServices method add the below:

services.AddApiVersioning(v =>
{
    v.ReportApiVersions = true;
    v.AssumeDefaultVersionWhenUnspecified = true;
    v.DefaultApiVersion = new ApiVersion(1, 0);
});

 

The above three properties are particularly useful in that they allow default versions to be set if none are explicitly set as well as providing header information on versioning that are supported.

ReportApiVersions: we are requesting the header to respond with supported API versions

AssumeDefaultVersionWhenUnspecified: set the default version if none are explicitly requested

DefaultApiVersion: Set the default version to 1.0 if default is used

To better illustrate the first property above see below. I used Postman to see the response header with supported versions listed, which I highlighted

Versioning_thumb7

Now all I have to do is simply add and update the controller attribute in my case

At the moment as I am still on version 1, I will add the attribute

 [ApiVersion("1.0")] 

and update the route attribute like so:

 [Route("api/{v:apiVersion}/[controller]")] 

So the result of the Controller class(GoalsController in my case) attributes should look like the below

Versioning_thumb1

Now let’s test our F5 and browse to our API endpoint with suffix : /api/1.0/goals, in my case below.

Versioning_thumb3

That’s it my API is now versioned v1.0

Adding Swagger to my ASP.Net Core API

I would like to show just how easy it is to add testing and documentation to your Asp.Net Core API using Swagger.

The reason I chose Swagger is simply that it is the largest framework of API developer tools for the OpenAPI specific which allows rapid documentation and testing of APIs with great ease.

For reference check out their website @ https://swagger.io/

First we want to add the Swashbuckle package from Nuget.

Right click your API project and click Manage Nuget Packages

Under the Browse tab search for Swashbuckle.AspNetCore

Package

Once found click install

Once installed we want to add the Swashbuckle namespace ‘Swashbuckle.AspNetCore.Swagger’ to our Startup class and in the ConfigureServices method the following:

services.AddSwaggerGen(c =>
{
    c.SwaggerDoc("v1", new Info { Title = "[Title]", Version = "v1" });
});

Replacing [Title] with the Title you would like to set

Next, In the Configure method within the scope of the env.IsDevelopment() check add

app.UseSwagger();

app.UseSwaggerUI(options =>
{
    options.SwaggerEndpoint("/swagger/v1/swagger.json", "[Name]");
});

Replacing [Name] with the API spec you would like to set

To try it out simply select one of the buttons corresponding to one of your API methods

Click the ‘Try it out’ button on top right

Then hit the Execute button

image

That’s it!

We’ve just added swagger, which will dynamically update as you add, remove or update your API removing the maintenance of separate documentation processes – fantastic.

Getting Started with Azure Service Fabric

I wanted to show a simple example of using Azure Service Fabric to create a reliable & scalable micro service that would perform addition functionality on an input string for example “1+1” using a console application as the client.

The string is parsed out to two integers and calculates the result. Obviously this is extremely simplistic type of example. I wanted to really just do a quick test on passing input and expecting output.

The code is listed up on my GitHub account under the ServiceFabric Repo.

ASP.NET Core Web API with Docker

This post simply demonstrates creating a simple service called ‘AdditionMicroservice’ that adds two numbers provided as query string parameters.

I will add this code to my GitHub account under Getting started with Microservices repo

Pre-requisites:

Docker for Windows

1) Create a new ASP.NET Core Web Application project

image

Select the Web API Template

image

Check the Enable Docker Support checkbox

Select Windows as the OS

Click

Open Values Controller file under Controllers

image 

Remove all other methods except first Get method and change to below as below

image

The change  launchUrl’s from api/value to api/addition in launchsettngs.json file:

image

Run the app and append to the URL both the x and y parameters along with their set values to view the result:

image

Resources that helped me pass the 70-483 exam

Well a few weeks back I passed the 70-483 Programming in C# exam, it had been several years since I took an exam so I did not know how I would do.

I had worked in c# for quite some time now but all of my knowledge was pretty much self taught on the job so I knew there were some gaps in my knowledge so I thought going for the exam would at least highlight the areas in which I need to focus on. Indeed there were some areas I had touched on very little throughout my career so it was definitely a worthwhile cause from that perspective alone.

In my previous employment I had the opportunity to attend the Microsoft official course for this exam which lasted a week which was really beneficial and was a great resource, however it was expensive and not sure I personally would have attended I have had to foot the bill. Other resources that I took advantage of where pluralsight courses, virtual academy jumpstart videos as well as the MCSD Certification Toolkit.

To mention the pluralsight course there is blog post covering this exam course : http://blog.pluralsight.com/learning-path-c-microsoft-exam-70-483 which indicates the videos to check out that would be specific to the exam areas, I cannot rate pluralsight enough to be honest I truly believe it to be one of my best subscriptions I cannot tell you the amount of information I have learnt over the years using this resource as well as solving many technical issues that I had faced – if you do not have a subscription I would encourage you to take advantage of their free trial.

The virtual academy jump start videos were awesome too : http://www.microsoftvirtualacademy.com/training-courses/developer-training-with-programming-in-c, the videos were very entertaining and the presenters knew their stuff best of all it is free so definitely check them out. It is a great resource for some free training.

Other than this plenty of hands on coding there is really no substitute for actual coding I believe it is not only the best way to learn as it will quickly let you know when you hit an area you do not truly fully grasp but also the best way to retain what you learn for longer.