What is integration testing?

The significance of Integration testing is rather simple - Integrate/combine the unit tested module one by one and examine the behaviour as a combined unit.

The most important purpose or goal of the testing is to check the interfaces between the units/modules.

After all of the individual units are made and tested, we begin blending those "Unit Tested" modules and begin doing the integrated testing.

The main purpose or goal of this testing is to check the ports between the units/modules.

The individual modules are tested in isolation. When the modules are unit tested, they're incorporated one by one, until all of the modules are integrated, to look at the combinational behaviour, and validate if the requirements are implemented correctly or not.

Here we should understand that Integration testing does not happen at the end of the cycle, rather it's conducted simultaneously with the development. So in the majority of the instances, all of the modules are not really available to check, and here is what the challenge arrives to test something which does not exist!

Why Integration Testing?

We feel that Integration testing is complex and requires some development and logical skill. That is true! Then what's the intent of incorporating this testing into our testing approach?

Here are some reasons:

In the actual world, when programs are developed, it's broken down into smaller modules and individual programmers are assigned 1 module.

The logic executed by a single programmer is quite different than another developer, therefore it becomes important to assess whether the logic implemented by a programmer is according to the expectations and rendering the right value in accordance with the prescribed standards.

Advantages

There are numerous benefits of the testing and few of them are given below.

• This testing makes sure the integrated modules/components operate properly.
• Integration testing could be started once the modules to be tested are available. It does not require the other module to be done for testing to be performed, as Stubs and passengers may be used for exactly the same.
• It finds the errors linked to the interface.

Challenges

Listed below are some challenges that are involved in integration testing:

• Integration testing means testing two or more integrated systems so as to ensure that the system operates correctly. Not just the integration links must be analyzed but exhaustive testing taking into consideration the environment should be done in order to guarantee that the integrated system works properly.
• Managing Integration testing becomes complex because of few variables involved in it like the database, Platform, surroundings, etc..

• While integrating any new system with the legacy system, it demands a lot of modifications and testing efforts. The same applies while integrating any 2 legacy systems.

• Integrating two distinct methods developed by two distinct companies is a huge challenge as for how one of the systems will impact the other system if any changes are done in any one of these systems isn't certain.