Basics Of API Testing

Every Information About How And Why You Should Use An API?


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In the process of enhancing your applications, you will ultimately come across a term known as Application Programming Interface(API). It is not possible to imagine recent development without APIs. Although this term has various definitions, so let’s begin. In this blog we will learn about why you should use an API, architecture of an API, what is an API, and need for APIs. So let’s get started.

What is an API?

API i.e. Application Programming Interface is like a clear language, the rules of which are shared by a specific service. You can teach your application the rules of a particular language, so it can convey the service. It will allow all the functions and information that the service is ready to share. In formal terms, we can say, API is an interface that enables your application to interact with an external service operating an easy set of commands. You do not require to know the internal logic of the service, only send a modest command and the service will return the essential data.

For example, if you desire to contact the news aggregator API and receive ten of today’s most popular news from it. You cite to the “top news” command (which the service elaborate in advance in the public domain), and in answer, the service will deliver you the latest collection of sensations.

Why you Should Use an API?


If there were no APIs, the functionality of your apps would be hampered, and the advancement time would increase reasonably. Any function that is not executed as a module on one of the programming languages would have to be developed alone. APIs tie disparate applications together, enabling them to complement each other.

The hotel selection service obtains an external API for identifying and categorizing photos of rooms, the same service itself through the API allows selecting and booking hotel rooms. Therefore enhancing the functionality of numerous travel applications. If there were no API, each application would be hindered to a narrow list of its functions. It will lack the possibility of enlarging it to something that others have already created and utilized for a long time. 

Benefits of APIs

Now let’s talk about the benefits of API as APIs authorize you to save time when developing and help not to formulate a bicycle. It is much more productive and more convenient to use the abilities of one of the APIs than to try to execute independently. “Why you should use an API?” hence, becomes an important question to ask.

Moreover, it will be confusing to get some functions and information other than through the API. Let’s take an example, a thematic selection of news, or a weather forecast, etc. APIs replenish your apps with modern technology. With APIs, you can educate your application on the latest image distinction and the methods of processing natural language.

Also read- Challenges Of API Testing

Types of APIs

There are four fundamental types of APIs:

1. Open APIs

Open APIs also are known as Public API. There are no constraints to permit these types of APIs because they are publicly accessible.

2. Partner APIs

One needs particular licenses or rights to access this type of APIs because they are not publicly available.

3. Internal APIs

Internal APIs Also is known as Private APIs. In this only internal systems expose this type of API, which is, thus, less known and frequently meant to be used inside the company. This type of API is used by the firms among the several internal teams to be able to enhance its products and services.

4. Composite APIs

This type of API combines varied data and service APIs. It is a cycle of tasks that run synchronously as an outcome of the performance and not at the proposal of a task. Its central uses are to speed up the process of implementation and enhance the performance of the listeners in the web interfaces.

Example of API

An API specification can seize various forms, but constantly includes specifications for routines, object classes, data structures, variables, etc. Windows API, POSIX, and ASPI are examples of different forms of APIs.


Endpoints are the key components in the interaction of your application with the API. Usually, it is a particular address (for instance,, by quoting to which you get entry to particular features or functions (in our case we can say “a list of top news”). Generally, the name, i.e. the address of the endpoint conforms to the functionality it contributes. If you want to learn more about endpoints, we will glance at another illustration, this time within the RapidAPI service. This service is an API Hub delivering the proficiency to access thousands of different APIs.

You do not require to instantly write a program or launch a Postman application to receive an idea of the potentials of the API. Let’s take for instance the Numbers API. This is an easy and free API delivering fascinating data about numbers and dates. You should enter its name in the search box in the RapidAPI service or move to the “Education” category from the “All Categories” list to discover the Numbers API section, and choose this API from the list. Numbers API through RapidAPI is of no cost, it is easily available free of cost, so you can utilize it as many times as you need.

Once you choose Numbers API, the initial page you’ll see is the API Endpoints subsection. This comprises most of the data required to get begun. From the existing subsection (Endpoints), we can test the API endpoint rapidly in the browser by altering the input for the endpoint. Once you generate a request to the API by using the ‘Test Endpoint’ button. You will also see the reply directly on your browser.

Request Methods

As we have dealt with the basics of the API, let’s go a little further. Now let’s deal with Request Methods, using which we can communicate with the API. Without getting into too much fact, Request Methods describe what action we are going to take by suggesting to the API.

Here are four main types of actions:

  1. You should “get” an appeal for information from a server. This is the broadest type of request.
  2. You should “post” ads and current data to the server. By doing and using this type of request, you can, for instance, add a fresh contact to CRM
  3. You should “put” changes into the information. For example, utilizing this type of request, it would be feasible to change the colour or value of a subsisting output
  4. You should “delete” prevailing information

How to Start Using an API?

Here is a step-by-step guide that we are sharing with you all so that you can start using an API on your own.

1. Get an API key

An API Key is an extraordinary string of letters and numbers. You will be required to add an API key to each request so that the API can recognize you. To get an API key, you have to register with the API server and fill your identity details. On the illustration of RapidAPI – you can select the process of registration that will be convenient for you. This can be a username, email, and password just like Facebook, Google, or Github account.

2. Test API Endpoints

After we collect the API key, we can cite the API endpoints, according to the rules in the documentation, to examine if everything works as we expected or not. For this, we can utilize a REST client like Postman. In the case of RapidAPI, our life is much easier.

3. Create your first App

After we surveyed the endpoints and everything works as we wanted, we can start building the application, comprising calls to the necessary API. In this course, RapidAPI can also facilitate our lives. On the page of the API we require, we can use the Code Snippet block. We can select our best programming language and directly get the code that executes the task that we have just tested.

Talking about the code snippets, they are now accessible through RapidAPI for such programming languages such as:

  1. NodeJS
  2. PHP
  3. Python
  4. Ruby
  5. Objective-C
  6. Java
  7. and C#

APIs are a vital part of the contemporary development ecosystem. As you know everything now you can use them to widely expand the facilities of your application. If you have already read through the entire article, it is needless to say that the answer to “why you should use an API?” is well-established.

Also read- Basics Of API Testing

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