If you use Test Driven Development for your Node.js project uses Express library, you need to write unit tests among other things. As I experienced, testing code parts which use third party libraries are usually difficult for less experienced developers. The key aspect of effective unit testing is define boundaries of the business logic to be tested.
When I write unit tests including any structural items of the Express library, it produces me I have to avoid testing the library itself. It’s not my job. Rather than only my business logic needs to be tested. As for the middleware, it’s the logic inside the middleware function. The input parameters are coming from the Express library, so you need to mock or stub them.
An Express middleware is a special function which has three parameters: a request, a response and a next function. These are coming from the library flow, and you just need to wire the middleware to the proper level (application, router, etc.).
The most common problem with typescript is that a lack of knowledge of the type system that forces the programmer to try to bypass the own type system instead of taking advantage of its potential. Don’t do that! Express provides you its types for the requests (Request), responses (Response) and even for the next function (NextFunction).
#nodejs #expressjs #typescript #testing #jest
Automation and segregation can help you build better software
If you write automated tests and deliver them to the customer, he can make sure the software is working properly. And, at the end of the day, he paid for it.
Ok. We can segregate or separate the tests according to some criteria. For example, “white box” tests are used to measure the internal quality of the software, in addition to the expected results. They are very useful to know the percentage of lines of code executed, the cyclomatic complexity and several other software metrics. Unit tests are white box tests.
#testing #software testing #regression tests #unit tests #integration tests
The shift towards microservices and modular applications makes testing more important and more challenging at the same time. You have to make sure that the microservices running in containers perform well and as intended, but you can no longer rely on conventional testing strategies to get the job done.
This is where new testing approaches are needed. Testing your microservices applications require the right approach, a suitable set of tools, and immense attention to details. This article will guide you through the process of testing your microservices and talk about the challenges you will have to overcome along the way. Let’s get started, shall we?
Traditionally, testing a monolith application meant configuring a test environment and setting up all of the application components in a way that matched the production environment. It took time to set up the testing environment, and there were a lot of complexities around the process.
Testing also requires the application to run in full. It is not possible to test monolith apps on a per-component basis, mainly because there is usually a base code that ties everything together, and the app is designed to run as a complete app to work properly.
Microservices running in containers offer one particular advantage: universal compatibility. You don’t have to match the testing environment with the deployment architecture exactly, and you can get away with testing individual components rather than the full app in some situations.
Of course, you will have to embrace the new cloud-native approach across the pipeline. Rather than creating critical dependencies between microservices, you need to treat each one as a semi-independent module.
The only monolith or centralized portion of the application is the database, but this too is an easy challenge to overcome. As long as you have a persistent database running on your test environment, you can perform tests at any time.
Keep in mind that there are additional things to focus on when testing microservices.
Test containers are the method of choice for many developers. Unlike monolith apps, which lets you use stubs and mocks for testing, microservices need to be tested in test containers. Many CI/CD pipelines actually integrate production microservices as part of the testing process.
As mentioned before, there are many ways to test microservices effectively, but the one approach that developers now use reliably is contract testing. Loosely coupled microservices can be tested in an effective and efficient way using contract testing, mainly because this testing approach focuses on contracts; in other words, it focuses on how components or microservices communicate with each other.
Syntax and semantics construct how components communicate with each other. By defining syntax and semantics in a standardized way and testing microservices based on their ability to generate the right message formats and meet behavioral expectations, you can rest assured knowing that the microservices will behave as intended when deployed.
It is easy to fall into the trap of making testing microservices complicated, but there are ways to avoid this problem. Testing microservices doesn’t have to be complicated at all when you have the right strategy in place.
There are several ways to test microservices too, including:
What’s important to note is the fact that these testing approaches allow for asynchronous testing. After all, asynchronous development is what makes developing microservices very appealing in the first place. By allowing for asynchronous testing, you can also make sure that components or microservices can be updated independently to one another.
#blog #microservices #testing #caylent #contract testing #end-to-end testing #hoverfly #integration testing #microservices #microservices architecture #pact #testing #unit testing #vagrant #vcr
In the previous blog we saw that what exactly is Agile testing and in this blog we will see in introduction to Principles For Agile Testers.
#api testing #integration testing #quality assurance (qa) #testing #unit testing #agile #agile teams #agile transformation #agiledeveloper #automation #automation testing #testing skills
When we talk about Agile the first thing that pops into our mind is Agile development. But here we are going to see and learn about an introduction to Agile Testing that how testers work in Agile, the contrast between Agile Testing and development, and traditional vs. Agile approach.
The roles are divided into mainly two teams:
#agile #api testing #integration testing #quality assurance (qa) #scaled agile #scrum #testing #unit testing #agile teams #agile transformation #test automation
Certain truly external systems may be difficult to integrate into tests. This is because they have side effects in the real world that cannot be undone: A financial transaction, an email send, physically moving a paint robot. Before you give up and sidestep them in your testing, look around for solutions.
Many external systems will have a documented way to use them in an integration test. Payment processors often have test credit card numbers, and test users with test email accounts can be set up for testing delivery. The closer integration tests are to real-world interactions the more likely they are to catch problems and provide real value.
#testing #unit testing test #integration testing