API stands for Application Programming interface details regarding how some software components must act together. In general terms, API testing is a set of procedures and functions allowing the creation of apps accessing data or features of an operating system or application. All in all, testing of such procedures is acknowledged as API testing.
There can be numerous reasons behind executing API testing and there are a number of tests that can be performed on APIs. Some common API test examples are as follows:
2. In case some interruption arises during the process or any other event is prompted, you can call to another API
3. Tests for inputting condition based return values can be performed
4. With the help of these tests some resources can be easily modified like process killing, update of the database, etc.
5. The return values can also be tested which can be even null or are with wrong results
During the API testing process, a request is raised to the API with the known data. This way you can analyse the validation response. Basically, things that must be checked during performing API testing are:
2. Schema validation
3. HTTP status codes
4. Data type, validations, order and completeness
5. Authorization checks
6. Implementation of response timeout
7. Error codes in case API returns, and
8. Non-functional testing like performance and security testing
To set up the test environment of API is not a cake walk. It is bit complete and demands the configuration of the database as well as server according to the need of the software. There is no availability of GUI (Graphical User Interface) in this form of testing.
There are certain factors that determine the API testing approach. Let’s check them below:
2. Verifying the calls of the blend of two or more than two value added parameters
3. Defining the basic functionality and scope of the API program
4. Writing suitable API test cases and making use of testing techniques like equivalence class, boundary value, etc. to verify the functionality
5. Testing case execution
6. Testing result comparisons with the results expected
7. Verifying behaviour of API under conditions like the connection with files etc.
UI testing means the testing of graphical interface. It‘s focus is basically on the feel and look of an application. Within user interface testing, things like how user interacts with app elements such as images, fonts, layouts, etc is checked.
Many protocols are there that can be used in API testing. These are as follows:
JMS, REST, HTTP, UDDI and SOAP
There are many tools available that can be used for API testing. A few of them are:
Postman, SoapUi Pro, Curl, and Alertsite API monitoring
The term SOAP refers to Simple Object Access Control. In simple terms, it is an XML based protocol that helps in exchanging information among computers.
For testing API’s one must follows the below-mentioned steps:
2. Now choose the test development mode
3. Next demands the development of test cases for the required API methods
4. After this you need to configure the control parameters of the application and then test conditions
5. Once done with all the previous steps, configure method validation
6. Now is the time for execution of the API test
7. After this you can check test reports and filter API test cases
8. Last but not the least, sequence all API test cases. That’s it!
REST API is a set of functions helping developers in performing requests along with receiving responses. Through HTTP protocol interaction is made in REST API.
The main areas that need your concentration while writing API documents area as follows:
2. Plan or sketch of your document
3. Delivery layout of the same
4. Information needed for each of the function available in the document
5. Lastly, automatic document creation programs
The API framework is easy to understand. During the process, config file is used to hold the configurable parts as well as to value the test run. Besides, within config file automated test cases hould be represented in the format of parse table. During the process of API testing, it is not mandatory to test each API as a result the config file contains some sections whose API is activated for all that specific run.
The term Input injection is the act to stimulate user input. User input can be simulated in many different ways such as:
2. Invocation with the help of accessibility interface
3. Doing simulation with the help of low-level input
4. Doing simulation with the help of a device driver
5. Doing simulation with the help of a robot
To test APIs, Runscope is used. It is basically a web application providing backend services as well as an easy to use interface.
The list of major challenges that come while API testing are:
2. Parameter Selection and
3. Call Sequencing
There are various principles of API test design. Those are as follows:
2. Execution: during this principle, there are steps to follow API or scenario as well as logging
3. Verification: for evaluating the execution outcome there is oracles
4. Reporting: keep a tab on pass, blocked or failed
5. Clean up: this shows pre-test state
API is capable of finding many types of bugs that includes:
2. Security
3. Duplicate or missing functionality
4. Reliability
5. Unused flags
6. Performance
7. Incompatible error handling
8. Multi-threaded issues, and
9. Improper errors
While doing API testing and Unit testing, both targeting source code. In case an API method is making use of code based in .NET then other tool which is providing support must have .NET
There are various automation tools for API testing:
2. Soap UI
3. JUnit for Java
4. NUnit for .Net
For any foundation, there is always a need of good documentation. Similarly API documentation provides as a quick reference to access working or library within a program.
2. Type and syntax of error message that may occur
3. Syntax, elements and sequence needed for each parameter
4. Links regarding functions
There are various API documentation templates that are making the whole process really simple and easy. Check them below:
2. Miredot
3. Slate
4. FlatDoc
5. API blueprint
6. RestDoc
7. Web service API specification
1. Where Unit testing is a form of white box testing, API testing is a form of black box testing.
2. Unit testing is performed prior to the process of including the code in the build. On the other hand, API testing is done after the build is prepared for testing.
3. In the Unit testing, the source code is drawn in the form of testing while in API testing the source code is not drawn in.
4. In the Unit testing, there is the limited scope of testing as a result only basic functionalities are measured for the purpose of testing. Subsequently, in API testing there is wide scope of testing, thus all the issues that are functional are measured for the purpose of testing.
5. Unit testing is done by the testers and where in every functionality is separately tested. While The API testing is done by the testers for the purpose of end to end testing of the whole functionality.
TestApi can be explained as the test building blocks library which is indispensable for testers and developers to create testing tools and automated test suites.
When something is not going as per expectations like when the outcome is not as predicted then the occurrence of errors can be seen and for the same warnings are explained in the form of a message in a proper format. Within a single module, there can be one or many warnings.
2. Documentation errors
3. Parameter validation errors
4. And some standard error messages
API Builder is a PLSQL utility that includes 4 square files. To place API parameters and to begin the technique only one report is liable. API builder allows you to create and make use of API endpoints that can be guzzled by any client application.
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