Deploy Spring Boot Applications With More Confidence and Fewer Regressions
Build Better Spring Boot Applications: A Comprehensive Testing Course to Boost Your Confidence and Productivity
LIMITED OFFER: 3 for 1 offer when enrolling for the Bundle or Coaching edition. Get two additional resources (eBook & online course) on top.
TL;DR: This online course is a deep-dive on effectively writing unit, integration, and end-to-end tests for Spring Boot applications to become more confident and productive.
Knowing How to Effectively Test Separates the Serious Engineer from a Hobby Developer
“Quality is not an act. It is a habit.” – Aristotle
Do you remember writing your first Spring Boot application? You were excited that you now finally expose data via an API and can connect to a database.
Testing your application was the last thing you could think of at this moment.
Once you start using Spring Boot in a professional environment there is no way around testing. Testing your application gives you confidence, fearless deployments on Friday afternoons and a good night of sleep.
Most tutorials and courses about testing barely go beyond the Hello World example of testing a calculator.
This does not prepare you for the real world where your application faces database access, external systems, messaging system, network, etc.
There are so many great libraries and techniques out there for the Java ecosystem when it comes to testing. Mastering them all, right after you understand the basics about Spring Boot, is hard.
Testing is joyful once you are familiar with all the great tools you have access to: JUnit, Mockito, AssertJ, Hamcrest, JsonPath, JSONAssert, Testcontainers, Selenium, LocalStack, Awaitility, and not to forget the whole Spring Testing support.
Especially with Spring Boot you get so much functionality when it comes to testing. What you need are recipes to tackle testing different parts of your applications and then apply them.
This Testing Spring Boot applications Masterclass is all about making you an expert when it comes to testing Spring Boot applications in an efficient way.
All You Need to Know About Testing
Spring Boot Applications
The number of testing libraries is huge in the Java ecosystem. One might get overwhelmed with all the different solutions.
This online Masterclass guides you through every testing library you need to verify your Spring Boot application is working as expected.
After working with this course, you not only have recipes at hand to test different parts of your application, but you are also familiar with industry best practice.
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Enroll now and never worry about testing your Spring Boot Application again!
NEWS: Up-to-date with Spring Boot 3 and Java 17
Your Journey to More Confident Releases
Here’s What You’ll Learn In Detail
Whether you just started with Spring Boot or are already using it in several projects, this Spring Boot Testing Masterclass guides you through all relevant parts of testing Spring Boot applications.
Understand What and How to Test
You are unsure which parts of your application to test? There is a good chance that you are not focusing on the relevant parts of your application you should test.
Go Beyond Trivial Unit Testing
After working with this course you'll have recipes at hand to test all non-trivial parts of your application like database access, HTTP communication, using cloud services (e.g. SQS from AWS), etc.
Master Different Testing Libraries
Not only will you be able to use all presented testing libraries for your application, but also understand what they are about and when to use which. Knowing when to use which library is a key skill.
Testing Best Practices
This Masterclass includes an own section about industry best practices for testing applications. Make use of knowledge from years of writing tests for enterprise applications.
Here’s What the First Early-Bird Students Say About This Course
Testimonial via Mail
Philip has made a fantastic overview of the full testing landscape of Spring. The videos are clear and explain details and common pitfalls in great depth. Looking forward to the rest of the course.
PS: Wim is also book author of Taming Thymeleaf and Practical Guide to Building an API Back End with Spring Boot.
Detailed review of the Masterclass on his blog
I got an opportunity to review the course I find it wonderful for learning how to test Spring Boot applications leveraging modern testing frameworks and libraries....
I would highly recommend Masterclass for anybody working with Spring Boot applications.
Read the full review here.
Overview of the different Masterclass Modules
Module 1: Introduction
We'll start with an application walk-through, to get you familiar with the code base we test throughout the Masterclass.
At the end of this module you'll be able to start the Book Reviewr application and its infrastructure components on your machine.
Module 2: Testing With the Spring Boot Starter Test
Getting familiar with the swiss-army knife that every Spring Boot project includes: Spring Boot Starter Test.
We'll cover all testing libraries that come with this starter and take a detailed look into testing with JUnit 5 and mocking with Mockito.
Module 3: Testing Database Access
Start writing efficient tests for your database layer while utilizing Spring Boot test features like @DataJpaTest, TestEntityManager, @Sql, etc.
Furthermore, with this module you'll start using Testcontainers to replace the default in-memory database, learn how you can pre-populate your database, and understand the pitfalls when writing tests where the EntityManger is involved.
Module 4: Testing the Web Layer
MockMvc to the rescue!
Learn how to effectively test your web-layer (@RestController and @Controller) in isolation. You have your endpoints secured with Spring Security? No problem! There is great support available to ensure only authenticated users with the correct privileges reach your endpoints.
Module 5: Testing Further Slices of our Application
Ever wanted to know how to test your WebClient or RestTemplate HTTP calls? How to ensure your business logic is working as expected and how to verify your messaging controllers?
In this module, we'll tackle further slices to effectively test different parts of our application in isolation. In addition, we'll write our own test slice.
Module 6: Writing Tests With the Whole Spring Context
It's time to write integration tests using @SpringBootTest!
With the knowledge of previous modules, we can mock almost any external infrastructure component, except Keycloak. We'll introduce WireMock to mock the HTTP interaction with the identity provider or any other system during application startup (e.g. Salesforce, Stripe, SAP, etc.).
Module 7: Writing Web Tests
Writing end-to-end tests to ensure users can interact with your application.
Having automated web-tests for your happy-paths can literally save your ass. We'll make the most of Selenium and Selenide by verifying the Book Reviwr application without any manual WebDriver setup (including VNC recording, screenshots on failure, etc.).
Module 8: Testing Best Practices
Build tool configuration, test strategies, naming strategies, testing static methods, working with time, test report visualization within your CI (e.g. Jenkins, GitLab CI, Azure DevOps) server, etc.
... and last but not least: Drastically reduce your build times with Spring's Context Caching mechanism.
Talk Is Cheap, Show Me Some Real Lessons!
Your The Course Instructor:
Philip is an independent IT consultant living in Berlin. He started working with Java back in 2015 and has used it together with Spring Boot for multiple applications in several industries. Testing is an integral part of his daily work as he is a profound craftsman.
Once Philip understood the ins and outs of the Java testing landscape, writing tests makes as much fun as writing production code for him. He's a won around TDD (Test Driven Development) practitioner and regularly shares testing techniques among his colleagues and clients.
He started teaching Java topics on YouTube in 2018 and is writing content about the Java ecosystem on his blog since 2017.
More than 10.000 course students have enrolled for his online courses. Besides that, he's also actively helping developers on Stack Overflow with their questions around testing Java applications.
Here’s What People Are Saying About the Course Instructor
Philip is a dedicated developer and doesn't give up until he has understood the details of a topic.
In his courses and articles, he transfers this knowledge to you and they leave you smarter than before.
Looking forward to working with you in the future, Philip
Philip is a very skilled content creator who managed to publish high quality articles and videos that cover a wide range of topics, like Spring, Java EE, or Jakarta EE.
He pays a lot of attention to details, so if you enjoyed his articles and videos, you are surely going to love his video courses.
How can you not love what Philip is doing?
Tons of actionable tutorials and content across the Jakarta EE and Spring universes.
Why You MUST Invest Time in Learning How to Test Spring Boot Applications
When was your last outage or downtime caused by a bug that could have been prevented with a test? How much did your company lost in direct revenue or indirectly by losing customer satisfaction? How less productive are you and your coworkers because of missing automated tests?
Putting in numbers is hard, but I guess every minute a non-trivial application is not working as expected results in costs or lost revenue of $100.000+.
On the other side, consider how uncertainty paralyses you when you want to refactor an existing code base that lacks tests. Or you are new to a project and want to introduce a new feature. Testing things afterwards manually is a cumbersome and repetitive tasks.
We, as engineers, are lucky to have tools around us that can automate such cumbersome and repetitive tasks. So let's start using them by learning how to effectively test our applications.
Once you know your testing toolkit, writing tests becomes joyful.
Introduction to the Masterclass
Keeping the Course Content Up-to-Date
Spring Boot 3 Migration
Setup for Java Development
Infrastructure Setup With Docker Compose
Flyway Migration Scripts
AWS SDK Overrides
Introduction to the Backend Code
Keycloak Configuration Walkthrough
Testing With the Spring Boot Starter Test
Introduction to the Spring Boot Starter Test Dependency
Anatomy of the dependency
Managing library versions
Introduction to JUnit 5
Writing Your First Test With JUnit 5
Verify the Test Outcome With Assertions
Lifecycle of a Test
More on Assertions
Specifying the Name of a Test
Write Parameterized Tests
Your First JUnit 5 Extension
Parallelization of Tests
Introduction to Mockito
Introduction to the Class Under Test
Mocking Method Calls With Mockito
Your First Test With Mockito
Mocking the Behaviour of the Repository
Instrumenting a Mock to Throw an Exception
Full Happy-Path Test With Mockito
Capture Method Arguments and Verify Invocations
Additional Test Libraries of the Starter
Introduction to Hamcrest
Introduction to AssertJ
Introduction to JSONAssert
Introduction to JsonPath
Spring Boot Starter Test Summary
Spring Boot Starter Test Conference Talk
Testing Database Access
The Secret Weapon to Test Your Database Layer: @DataJpaTest
Introduction to the JPA Domain Model
What to Test When Using Spring Data JPA
Start Using @DataJpaTest
Resolving context startup errors
Why and When to Use the TestEntityManager
Pitfalls of the First Level Cache
Using P6SPY for More Insights
Replacing the In-Memory Database
The Rationale Behind Not Using In-Memory Databases
Using Testcontainers for the First Time
Managing the Lifecycle of a Container
Improve Build Times by Reusing Containers
Solutions to Pre-Populate Your Database
Testing the Native Query
Recap of the Database Access Module
Testing the Web Layer
The Secret Weapon to Test Your Web Layer
Why Unit Tests Are Not Enough
Introduction to @WebMvcTest
Getting the Setup Right
Defining On Which Level to Mock
Your First Test With @WebMvcTest
More Tests for the BookController
Introduction to the ReviewController
Verifying the First Behavior
Testing the First Secured Endpoint
Additional Ways to Provide Authentication
Happy-Path Testing For Creating Reviews
Ensure We Validate Incoming Reviews
Access to Role-Based Secured Endpoints
Recap and Learnings of This Module
Testing Further Slices of Our Application
Testing HTTP Clients Using the RestTemplate
Introduction to Testing HTTP Clients
The Power of @RestClientTest
First Test Using the MockRestServiceServer
More Assertions for the Happy-Path
Handling Partial Responses
Test a Failure of the Remote System
More Expectations on the HTTP Request
Testing HTTP Clients Using the WebClient
Required Setup for the MockWebServer
Testing the Happy-Path Using MockWebServer
Verify Behavior on Partial Responses
Testing Failure of the Remote System
Implement and Test Retry Mechanism for More Resiliency
Testing Business Logic in Isolation
Which Logic to Verify
Getting the Setup Right for Testing the ReviewService
Verify the First Error Scenario
Ensure We Don't Store Reviews With Bad Quality
Happy-Path Testing For Storing a Review
Testing a Custom Application Slice
Choosing the Application Part for Isolated Testing
Introduction to LocalStack
Creating a Spring Application Context With Only One Message Listener
Understanding the Spring Cloud AWS Auto Configuration
Overriding the AWS SQS Client
Creating a Local SQS Queue and Applying the Configuration
Happy-Path Testing For the Whole Listener Process
New Spring Cloud AWS Sliced Test Context Annotation
Recap on How to Create a Sliced Spring Context for Testing
Writing Tests With the Whole Spring Context
Remaining Setup to Start the Whole Spring Boot Application
What's Currently Missing to Start the Whole Context
Creating an Integration Test Profile
First Try to Start the Whole Context
Introducing WireMock to Mock HTTP Communication
Creating an ApplicationContextInitializer for WireMock
Mocking the OpenID Configuration Response
Mocking the JWKS (JSON Web Key Set) Response
Making Use Of the WebTestClient to Access the Backend
Creating a Valid JWT to Access Our Endpoints
Writing Integration Tests for Our Application
Verifying the Book Synchronization Process
Refactor Our WebClient to Mock the HTTP Response
Extract Integration Test Setup to a Central Place
Ensure Users Can Create Reviews
Develop the Missing API Endpoint Test-Driven (TDD)