Integration Testing is about combining the individual modules and test whether the interfaces work as expected, that is, calls to procedures and functions are made as per requirements.
Interfaces in Integration Testing are as follows:
Verify the Layouts - Check if the fields like text boxes, check boxes, list boxes behave as expected. For instance a text box must allow an input that fulfils the specifications like range validations, types of characters allowed etc., field formats, whether the page title is displayed at the appropriate location and so on. Layout verification thus aims to check whether the overall presentation of a page is as per requirements.
Button Layout - In this context, the name of a button must be meaningful. Also, it must perform the function as per the name assigned to it. It is very important for a tester to run the test scripts to ensure that as a button is clicked, the script of that page must call the right function.
Field Validations - By field validation we mean adherence to constraints or conditions defined for each field. For example, an email field must adhere to the email format specification, a password field must restrict a user from entering invalid characters or length, a numeric field must not allow any characters other than numbers and so on.
Drivers - This is regarding verification of navigation bars to take a user to a specific page, a user request takes him to the desired landing page.
Processing - Test whether after an action is performed, clean up of data is performed. Database operations like insertion, deletion and updates should be done with an intimidation to the user.
Validating Relationships - It is important to verify whether the association of controls is functioning as per specifications. Like checking table conventions, constraint definition conventions etc. are in the right order.
Verification of menu items and their functionality.
Adherence to coding standards and practices.
Testing user access privileges.
Test all the network features, like a request is passed over a HTTPS protocol or not.
Check for proper functioning of the plugins, whether auto updates are working as expected.
Pre-installation testing is necessary to make sure that all previous data is deleted, which is not necessary in the current installation process. It is also important to verify whether the required environment set up for the application to be installed, is met or not.
After installing the application on the system, the tester verifies whether the installation gives rise to any other error conditions or whether all the functions work properly.
Integration testing aims to test a software application by integrating the various unit interfaces by ensuring that interfaces among the modules are behaving as per programmed instructions.