API Testing Tools: Have you ever heard the acronym 'API'  and wondered what it is? Or were you ever intrigued to know what you can do with it? If the answer to the above questions is a Yes. Then let's get started with API and the best tools and practices in 2021. API or Application Programming Interface is a secure development environment that allows users to plan, create, and make necessary changes. In basic terms, APIs are a set of functions and procedures that lets you create an application that accesses data and features of other applications, services, or operating systems. Good APIs make it easier to develop a computer program by offering all the foundational blocks, which are then put together by the developer.

A real-world example

A real-world example is buying movie tickets online. You go to the movie site, select the movie, enter your name, card credentials, and VOILA, your seats are booked and tickets are printed. But what's exactly going on between entering your information and receiving your tickets? Well, the answer is APIs. They are integrating behind the scenes with other applications. You might wonder, how is this possible? This type of collaboration is called 'seamless' because you don't have a clue when the software role is passed from one application to another.

API Testing Tools - Why do we need an API?

For instance, perhaps you want to access all tweets under a particular hashtag. One way is to send a mail to Twitter and ask for a spreadsheet of all these tweets. But then you would have to find a way to import that spreadsheet into your app. Even if you store them in a database, the data would become outdated swiftly. It would be impossible to keep up with the data consistently. But wouldn't it be simpler and better for Twitter to just provide you a way to query their application to get hold of your desired data so that you can use it in your application. And the best part, it would be up to date automatically without any extra effort. So, here the API provides access to data, and that is included in various applications.

Types of APIs - API Testing Tools

  1. Open APIs - Public APIs are usually open for all. They hold no restrictions on accessibility and are publicly available.
  2. Partner APIs - Access to this category of APIs is gained through a licensure model.
  3. Internal APIs - They are custom-built for in-house enterprises. The organization tests the accuracy of its services/products usually with such APIs.
  4. Composite APIs - This differs from the above categories. In this, there is a sequence of processes triggered when a series of other tasks are executed.

 Tools for API Development - API Testing Tools

Developing an API isn't a cakewalk. To make your work easier, we've curated a list of the most recommended software testing tools in the market.

  • SoapUl - An open-source API development tool that facilitates testing both SOAP & Restful APIs for features like functionality, security, and performance. It runs on Java that in turn makes it easier for most operating systems to handle operations.
  • Postman - Allows API development and also provides you a testing environment for using the same JavaScript.
  • Katalon Studio - It provides an automation testing tool for API, mobile, and web. Katalon Studio deploys the BDD Cucumber framework that binds the gap in internal communications between company stakeholders and IT teams. As a result, the ongoing progress can be relayed to concerned people. DevOps tools such as Jenkins, Docker & Maven can be easily integrated with Katalan.
  • Apigee - It's a cross-cloud API management platform, designed and developed by Google Cloud, that allows you to pre-examine live session situations while working on proxy APIs. It also provides end-to-end API management support and has been in the top position in Gartner's Magic Quadrant report for the last 4 years.
  • TestNG- It was influenced by JUnit & NUnit testing frameworks of Java. This offers unit testing and integration in API development.
  • Rest Assured - It is inspired by languages like Groovy & Ruby. This API testing tool is based on Java and mostly for REST APIs. And the Key features include XPath validation, specification reuse, JSON path syntax, and easy file uploads. Web services that are based on JSON, HTTP, and XML can be tested on Rest Assured.
  • Apiary - Apiary is an end-to-end design and development solution facilitating mock environments for proxy testing.
  • Tricentis Tosca - DevOps environments have always aimed challenges at software developers, mainly for testing APIs. Tricentis has attempted to fill that void with a user-friendly interface that is more suitable for beginners.
  • MuleSoft API - It is also known as AnyPoint API Manager, developers get to choose from the pool of services. MuleSoft is mainly popular in the programming community, as it integrates with leading cloud services like SAP, and Salesforce. Mule is the official run time engine for APIs.

The must-have features in an API Design 

1. Filtered Search

The triggers are implemented to source data from APIs. Like any other coding language, developers need to be crystal clear about the who and why of changes, along with the trail of events. Records can be reconciled using timestamps, as the API has built-in flexibility to execute filtered search features.

2. Paging Sequencing & Sorting

It is considered a good coding practice when the user is not flooded with all changes at once, but we now have a log of changes that are time stamped. The paging feature can control both the frequency and volume of data a user is accessed, per session. This is all about optimizing the effectiveness of the API. It is convenient for the end-users if there is in-API functionality, which enables sequencing pages by timestamped changes and other ad-hoc conditions.

3. RESTful Support

REST is an architectural style, unlike traditional SOAP. And for a fact, RESTful APIs can be built on multiple standards like JSON, URL, HTTP, and XML. While SOAP APIs are mainly based on HTML & XML.

4. Authorization via OAuth

OAuth stands for Open Standard Authorization. Do you remember sharing your Facebook account information with third parties, do you share your passwords, as well? No. That's because Facebook has a backend OAuth feature. And this allows for such flexibilities while safeguarding privacy. This practice has become universal with API development for sharing user information with third-party sites.

API development practices

  • Throttling- This helps to regulate and direct the total frequency of queries on the API. It is customizable to such an extent that we can limit the access to people depending on days, months, or weeks.
  • Focus on API standards - API standards like OpenAPI and AyncAPI are expected to show a rise in their usage and relevance as they are a crucial aspect of development.
  • Streaming and Async APIs - If you're interested in executing a rich website that has more information and content, in such cases, you need to go for stream and Async API. These will allow you to lower the bandwidth, hence the cost of operation reduces. It will allow the data to be streamed to the end-user on various platforms and maintain high interaction with the users.
Conclusion: APIs are one of the most important aspects of your mobile application for website development. They can help in bringing the right user to your platform. In the end, no matter how much you have invested in your product, if it doesn't reach the right audience, there's no point in that hard work. Hence, learning and developing APIs, using their best practices and API Testing Tools, is crucial to make your project a success. Read More: ROLE OF API TESTING IN THE AGILE WORLD