TMG Security

Things You Must Know About API Before Using It

What is an API?

An application programming interface is a way for two or more computer programs to communicate with each other.

Types of API:

  • Why APIs are important?

    A Simple reason for API automation is required to weaken the chances of flaw detection at a later stage. One of the major features of API Testing is testing the API’s capability to perform under pressure. There are multiple toolsets and libraries available which are used to automate API calls and by that, we can create an API testing automation suite. It is required to make sure the final product is of the best version, ensuring the API implemented functions as planned in multiple factors like security, performance, etc. Here we can detect the bugs and defects at very early stages and save the costs along with cost along PI tests that are fast and simplify the validation of business logic, security, compliance, performance, and other aspects of the application.

    How Does an API Testing Work?

    Generally, APIs of an application are used to manipulate its resources in reading (GET), creating (POST), updating (PUT), and deleting (DELETE). Knowing the purpose of the API will set a firm foundation for you to well prepare your API testing data for input and output. All API response status codes are separated into five classes (or categories) in a global standard. The first digit of the status code defines the class of response. The last two digits do not have any class or categorization role.

    There are five values for the first digit:

    • 1xx (Informational): The request is received and continues to be processed
    • 2xx (Successful): The request is successfully received, understood, and accepted
    • 3xx (Redirection): Further action needs to be taken to complete the request
    • 4xx (Client Error): The request contains the wrong syntax or cannot be fulfilled
    • 5xx (Server Error): The server fails to fulfill an apparently valid request
    Environment: Setting up the environment for testing can be complex as it does not involve any GUI, and all you do is play with parameters hit the database, and invoke APIs. Test Cases: Multiple test cases are written like what would be the return value, what if there is no response or a null one, what if another API is triggered — whether relevant or not, etc. Output: With different test cases, different out will be expected, and later it is important to compare the actual output with the expected output. Moving on, the errors that can be successfully detected in testing are security and performance issues, handling of unlike conditions, end-to-end working of a single functionality, structure of Response Data, ignored or absent functionalities, etc. These results assist in improving the API for further builds. Don’t forget to check out our Official API Pentesting Training
    Things You Must Know about API before Using