Integration Testing first RESTful web service with Kotlin and Spring Boot

We have been building a lot of infrastructure using Kotlin and Spring Boot -- And I am loving it! I have decided to start documenting parts of it for my own reference. I also hope my rant is useful to someone else, who's trying to solve similar problems :D

In this post we will be looking at building our very first RESTful web service using Kotlin and Spring Boot and writing an integration test for it. We will be using Gradle as our build tool.

Gradle File

First important component in the puzzle is the Gradle file. Following is the complete gradle file that we will be using for this post. Notice the use of all-open plugin. This is needed so that Spring can Autowire dependencies into our Kotlin classes.

Code

Lets create a very simple Book data class, it has got properties like title and author.


Adding a BookController, it has only one method which serves the requests from /books/search?title={title} path. This method will return the details of the books whose titles contain the searched term.

Note: The books collection is hardcoded for this example but nothing stops us from getting it from an external source, e.g. a database.


Next we need to add the application class which will expose the main method.


Test

The fun part about Spring Boot + Kotlin is the ease of testing this service. We will test this service out in two ways

• Testing the API in browser
• Writing a integration test 

Browser Test

• Boot up the server using the following command
• If everything goes great you should see a message informing that the server is up and running.
• Open up the browser and open the http://localhost:8080/books/search?title=Steve
• You should see the following response in the browser

Integration Test

Spring Boot provides a convenient class TestRestTemplate to test out the REST api's. Here is an example test for testing our API

As you run the test, notice that it boots up the server, invokes the api and fires the asserts on the responses!

Bonus

The toJson and fromJson methods are extension methods, they convert Objects into JSON representation and visa-a-versa. I use them all the time, they are pretty handy!

Project Structure

The best way to show this is via a screenshot.

Thats about it, we have a web service written in Kotlin using Spring Boot and we have successfully written a test for it as well!

PS: Here is the complete source code of the example used in this post

Review of - The Selenium Testing Tools - Beginner's Guide

As mentioned in one of previous post, I got an opportunity to review a book on Selenium call - The Selenium Testing Tools - Beginner's Guide from PACKT Publishing.

Selenium 1.0 Testing Tools: Beginner’s Guide

I had used Selenium in lot of my projects, I thought, I knew selenium quiet well before reading the book.  After reading the book, I realized that, I had only partial knowledge about Selenium.  I knew how to do things, but the book taught me, how to do them in many different ways and what was the best way in a given situation.

The book, taught me lot of new things about Selenium.  For example, I always thought that, using Selenium IDE, one cannot write maintainable tests, but after reading the book, I realized that if one follow the patterns mentioned in the book, one can easily write maintainable tests simply using Selenium IDE.

Moreover, non-programmers can convert the Selenium IDE tests to programming API tests in a matter of few clicks!

There are may good things that, I could take away from the book, here are a few that stood out:

• Starts of from the very basics.  The book start with installation of Selenium IDE, Firebug and Firefinder add-ons to Firefox.  Because of this, someone who has never worked with selenium before, can quick start and write their first selenium tests in a matter for minutes
• While reading some books, I get lost and have to figure out how to do a certain step.  But things are different with this book, there are screenshots for almost every thing.  For every step that book shows there is a Screenshots.  This helps us understand the concepts in a much better way.
• Book encourages the use of best practices.  For example, book clearly explains why the test cases should be independent of each other and how one could achieve that.  Book encourages the use of Firebug and Firefinder.  These are two tools which every web-develop/web-QA should know for sure!
• Explains how one can convert Selenium IDE test to programming tests using just the Selenium IDE.  I did try it and it does work!
• Book Explains how we could use Selenium Grid to parallelize our tests.  Using Selenium Grid we could target our tests to run on a certain browser on a certain OS.  For example, we could configure that Test1 should run on "Firefox on Mac" or "IE on Windows".  Using this feature you can test your application on lot of platforms and browsers without a lot of pain!
• Demonstrates advanced techniques like Cookie handling using Selenium API
• A full chapter dedicated to Selenium 2
• At various steps, the book presents the user with Popup Quizzes, these are helpful to test what we have learned!
• Explains the Page Pattern.  While writing the Selenium tests using the Programming API, its extremely important that we do not repeat code for every test.  Book explains how we could achieve maximum reuse of code.  End result, more maintainable and easy to write/read tests!
• Explains various techniques like xpath, regexp, css and javascript to locate an element.  Its extremely necessary that we learn how to locate the element efficiently.  Using the right technique at the right place could result in faster and easy to read tests.  For example using xpath at a place where css could have been used would result in slower tests!
• Explains the use of user extensions.

Those are some of the take away's for me from the Book.  

The book has much more to offer than, what I have described here.  Take my advice, do not waste any time and grab a copy of the book from here!

Learning good things about Selenium - The Functional Testing Tool

Recently, I have been learning a lot of good things about Selenium. All thanks to this book, Selenium 1.0 Testing Tools - Beginner's Guide.

Selenium 1.0 Testing Tools: Beginner’s Guide

I got an opportunity to review this book from PACKT Publishing. I have just started reading the book, but I can tell you one thing, it gives great start at working with Selenium.

What is Selenium?

Selenium is an opensource automated testing tool for testing web application.  Using Selenium we can write test cases to test the web application in a black box environment.

Quoting from the book:

Test automation has grown in popularity over the years because teams do not have the time or money to invest in large test teams to make sure that applications work as they are expected to. Developers want to make sure that the code they have created works as they expect it to.


As time has passed developers and QA's have realized that automated functional tests provide a great safety net for catching bugs early in development life-cycle.  Selenium makes writing/executing functional tests extremely easily.

We can record and playback the tests directly in firefox using the Slenium IDE!  Selenium also provides programming api to write functional tests in Java, C#, Ruby , PHP, Perl and Python.

Once the tests are written (using the programming API or Selenium IDE) they can be execute as often as one wants using the Selenium RC (remote control) or Selenium Grid!  Over and above it the test can be executed in variety of browsers including IE, Firefox, Opera and Safari!

Selenium can be used to simulate any work flow.  I have been in situations where, because the team had written Selenium tests, a bug was caught early in the development life-cycle, which would otherwise be caught very late.  End result lot of time and money was saved because of Selenium!

The things I am blabbering (about Selenium) in this post are covered in much greater detail in the book.  Simply by reading the first few pages I was able to write a functional test using Selenium IDE.

Some of the good things I have noticed about the book so far:

• Starts from basics.  The book starts of by guiding users through the installation process of Selenium IDE.  Goes on to explain how to write a simple functional test (using Selenium IDE), with an example.
• Easy to read.  Its very important that books are written in simple language so that everyone can read it easily.  People with/without programming background can read this book with equal ease and extract useful information out of it.
• All concepts are explained using examples and lots of screen shots.

These are just initial impressions about the book.  I am sure, I will discover many more good things about the book, as I continue reading further!

Stay tuned folks!  Full review of the book coming up very soon!