Testing application programming interfaces (APIs) directly and as part of integration testing to determine if they meet expectations for functionality, reliability, performance, and security is considered API testing. API testing is a type of software testing that involves testing APIs directly and as part of integration testing to determine if they meet expectations for functionality, reliability, performance, and security is considered API testing.

1. Accelerating Software Product
Development with API Testing
We are experts in software product
development with deep proficiency in
offshore-based software development work
using Agile methodologies

2. Using APIs into your software development process
enables you to reorganize and arrange internal systems
in a consistent way to support innovative initiatives —
lowering costs and boosting agility. Additionally, it
enables the development of novel, creative methods for
reaching consumers, generating money, and forming
partnerships.
Most significantly, participating in the API economy
enables developers to deploy software more quickly in a
variety of ways.

3. What are API and API Testing?
An application programming interface (API) is a link that
allows computers or computer programs to communicate
with one another. It is a kind of software interface in which
one piece of software provides a service to another.
Testing application programming interfaces (APIs) directly
and as part of integration testing to determine if they
meet expectations for functionality, reliability,
performance, and security is considered API testing. API
testing is a type of software testing that involves testing
APIs directly and as part of integration testing to
determine if they meet expectations for functionality,
reliability, performance, and security is considered API
testing.

4. How does the API work?
The method we use while testing an API is determined by
the kind of product we’ve developed. API testing is
required regardless of whether you have a web services
API, an operating system API, a database API, or an API
for remote resource access.
Examples of API Testing

5. Whatsapp
You undoubtedly already use WhatsApp to communicate
with friends and family, but it offers amazing APIs for
companies as well. Twilio, for example, has partnered with
WhatsApp to create APIs that companies can use to
interact with its 1.6 billion users in over 180 countries.
Companies choose WhatsApp Business over SMS because
it offers a more customized “conversational commerce”
experience. They use APIs to connect to their customers’
CRM systems. This enables businesses to interact with
customers on WhatsApp to offer assistance, fast answers,
critical alerts, and highly targeted, content-rich messages.

6. Google Maps
In addition to Google Maps, you undoubtedly know a few
dozen additional applications that utilize Google Maps
APIs to extract customized location data, provide
instructions, and analyze location data that may help
companies better serve consumers, suppliers, and
delivery services.
Google Maps offers a variety of configurable, easy-to-
implement APIs that companies may utilize to improve
their location data and services.

7. Weather Snippets
The AccuWeather API collects comprehensive, reliable
meteorological data for virtually every place on the
globe, in more than 100 languages, and makes it
available to third-party developers. As if that wasn’t
remarkable enough, AccuWeather makes this data
available to customers for a charge, allowing them to
incorporate it into their applications via simple-to-
implement APIs.

8. How Are Different Types Of API
Testing Defined?
Now that we’ve defined API testing let’s examine how many
kinds of API testing are there. We’ve covered eight API tests
below that address the most frequent reasons we use REST API
testing in the first place. Concerns include the following:
● Recognize the API’s return value concerning the input
● Verifying if an API returns an incorrect response or nothing at
all
● Ascertaining if one API is making a call to another API or
triggering an event
● Establishing whether or not the API is linked to the data
structures
Now, let’s look at the many kinds of API testing that are
available.

9. 1. Evaluation of Functionality
Functional testing is a subset of API testing that validates
the product’s operating needs. These routines take
advantage of certain situations to ensure that the API
works as anticipated with the specified arguments. If the
outcome is not as expected, errors are rectified or
controlled.
For instance, functional testing may verify the layered
scenarios if you’re testing an API used to place music
orders online. It shows that the user often searches by
track or artist name, and a functional test would evaluate
if the correct input is provided.

10. 1. Evaluation of Functionality
Functional testing is a subset of API testing that validates
the product’s operating needs. These routines take
advantage of certain situations to ensure that the API
works as anticipated with the specified arguments. If the
outcome is not as expected, errors are rectified or
controlled.
For instance, functional testing may verify the layered
scenarios if you’re testing an API used to place music
orders online. It shows that the user often searches by
track or artist name, and a functional test would evaluate
if the correct input is provided.

11. 3. Testing Under Load
When an API is connected to many devices, it is essential to check for
possible disconnections. Reliability testing enables us to verify precisely that.
This test determines if the API will function correctly and consistently in any
given context.
2. Testing for Reliability
As the name implies, load testing determines if an API can handle
a certain level of demand. It examines how a specific API
performs when subjected to greater loads than it was designed to
handle.
Measure reaction times, check for harsh circumstances, assess
throughput, and evaluate other comparable variables in this kind
of test. The whole purpose is to observe how the system reacts to
comprehend the high load situation.

12. 5. Security Testing
Any API’s originality is defined by its potential to be utilized in novel ways. That
is what an API’s creativity testing verifies. It determines whether or not a
specific API may be used in various ways. Otherwise, creative testing shows a
poorly designed API.
4. Evaluation of Creativity
Security testing encompasses the API’s security requirements. Permissions,
authentications, and access restrictions are all included.
● The API authentication that you need
● Encryption is required to safeguard sensitive data.
● The resource management authorization checks and controls in place
These three elements show an API’s security hierarchy.

13. 7. Testing of API documentation
Proficiency testing is concerned with the API’s performance. It quantifies the
functionality it provides developers and the degree to which API operations
are feasible.
6. Proficiency Examinations
While documentation is often overlooked, it is critical for the development
team. The API documentation describes how to use the API. The API
documentation describes each complicated need, technical
requirement, and engineering requirement. The objective of API
documentation testing is to determine whether or not this document can
assist the user in extracting value from the API.

14. The Advantages of API Testing in
Development
Negative testing determines if your API is built to accept unexpected and
incorrect user replies smoothly. For instance, what would you say to the user if they
enter a number into a letter field? What message would you display? You may
display the message “Invalid answer.” Kindly type a letter.”
In addition, this test covers any incorrect user input.
8. Negative Testing
There are many advantages to integrating API tests in your test-driven
development process. The whole product development process is enhanced,
resulting in high-quality services to the end customer.
There are five critical reasons why an organization’s API testing procedure is
vital. Continue reading to learn more about these advantages.

15. 1. Consistency
As a general guideline, you should create API tests throughout
the development lifecycle, and these tests should verify the API
in sequence. If you cannot do this, you will be forced to create
API tests after the work is complete. That is, you would design
tests that are both practical and unbias. The flaw with this
approach is that you are more concerned with how the API
should function than with other potential vulnerabilities.
When you incorporate API testing with Selenium throughout the
development process, you can ensure that your API tests are
solid and thorough. These tests demonstrate long-term
advantages and affect the API’s overall quality. Because
you’ve decreased the likelihood of future errors, the API’s
grade has improved.

16. 2. Capacity
You can test for integration of multiple APIs- and check for the software’s
functionality, and performance. The API testing procedure aids in:
● Checking the code and determining whether it has any problems. This
prevents us from having to change a large portion of the code afterward.
● Exposing and locating bugs in the code through automated or manual
testing.
● API testing comprehends your product’s fundamental operations and
determines if the functionality meets the user’s expectations.
Is the API capable of enhancing the functionality of the program for which it
was developed?
API testing is a critical task that guarantees that your final product performs
optimally.

17. 3. Adaptability
There is no question that agile approach adoption is becoming popular at
the moment. Conducting GUI tests alone will not provide us with the
necessary results. Additionally, it demonstrates that it is improper to enable
testers to begin work after developers have completed their job. That is
inefficient.
We live in an era of continuous testing and agile development, which
necessitates API testing. It is critical to do API level testing on the whole
application. This is only feasible if the testing team is permitted to operate in
an agile fashion continuously.
It would be best to begin API testing early in the development cycle to
guarantee that all development endpoints are covered and verified.
Thus, when the dots are connected, API testing allows companies to increase
their agility. The agile nature of API testing itself benefits the team’s
management capabilities and the product’s performance/quality.
Improved communication between testers, developers, and consumers is a
significant advantage of an agile network.

18. 4. Coverage of Tests
When it comes to developing a high-quality product, you must
account for every possible software failure point. It contributes
to the development of consumer trust and increases the
product’s dependability.
Fortunately, API testing may reveal problems with the network,
API, services, and server during the development process.
These problems may be more difficult to resolve after the
product has been deployed.
This is because once your product enters production, you are
already responsible for developing new tests for new and
changing use cases. You conduct tests throughout
development and production to ensure that you provide the
product that the user desires.
API testing enables this by establishing an agile environment.

19. Conclusion
You will notice that one of the advantages of an API testing tool is the ability
to run tests in a variety of settings. You may replicate and reuse tests, as well
as share them. The reusability of the analysis contributes to the process’s
efficiency and quality.
5. Test Reuse
You may be asking what you will need to implement the API testing
procedure in your product development process. If this is the case, then
review the information below:
The initial step in API testing is to configure and use a testing environment
and the API’s required parameters. It entails configuring the server and
database to meet the application’s needs.

20. Thanks You
Content Source: Medium
Contented by: Mindfire Solutions