Rest Api Coding Interview Questions

Differentiate Between Soap And Rest

A direct comparison of SOAP and REST may not be possible as SOAP is a protocol while REST is an architectural style. However, there are some things to consider when making a choice between the two for your projects.

• Being a protocol, SOAP works on certain standards that must be strictly followed, while REST is just an architectural pattern that is used to design web services and follows certain constraints like client-server setup, statelessness, and cacheable response, layered system, and uniform interface.
• The functionality of SOAP is exposed to client applications using service interfaces, while uniform resource identifiers are used in the case of REST. The bandwidth requirement of REST is lesser compared to SOAP as the messages in SOAP carry a lot of information.
• REST offers more choices in resource format, including XML, text, HTML, images, video, and so on, whereas SOAP can only handle XML.
• As SOAP is just a protocol, it can be used by REST in its web services, but vice-versa is not possible.
• SOAP is useful when security is important in web applications. REST is not very secure and cannot be used when transactions must be done securely.

Have a more detailed understanding of REST vs. SOAP here.

Aspnet Web Api Interview Questions

18. What is ASP.NET Web API?

ASP.NET Web API is a framework and a perfect solution for developing RESTful applications on the .NET framework. Using the ASP.NET Web API framework, you can seamlessly create HTTP services to respond to a broad range of clients, including browsers and mobile devices.

Microsoft provides this framework for developing HTTP-based services on top of the .Net framework.

19. What are the advantages of ASP.NET Web API?

Here are some advantages of ASP.NET Web API:

• Well-suited for creating RESTful applications on the .NET framework.
• Works similarly to the HTTP using GET, POST, PUT, DELETE for performing CRUD actions.
• A flexible option for creating Web API.
• Supports routing.
• Supports model binding, validation, Odata, etc.
• Uses ApiExplorer for developing custom help and test pages.
• Can seamlessly create non-SOAP-based services, such as XML, JSON, etc.

20. What is caching? What are a few different types of caching?

Caching involves temporarily storing information for quick reference. It contains all the frequently accessed files in its memory. Whenever you re-access those files, the cache memory shows you the files, rather than leading you to the actual website again and again.

A few different types of caching include:

21. Explain content negotiation in Web API.

Content negotiation refers to the method of selecting the best possible representation for a specific response. There are two types of headers available for content negotiation:

• HttpResponseMessage

What Does Api Testing Mean

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.

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What Is The Major Obstacle Users Faced When Using Soap

When using SOAP, users often see the firewall security mechanism as the biggest obstacle. This block all the ports leaving few like HTTP port 80 and the HTTP port used by SOAP that bypasses the firewall. The technical complaint against SOAP is that it mixes the specification for message transport with the specification for message structure.

Q: What Is Jsonpath In Rest Assured Ans:

JsonPath is a simple way to get values from an Object document without having to use XPath. When retrieving an object from the document, it follows the Groovy GPath syntax. It can be thought of as a JSON-specific version of XPath. As an example, consider the following Object document.

}Response employeesResponse = RestAssured.given.request JsonPath jsonPathObj = employeesResponse.jsonPath //get a list of all employees id:List< String>  employeeIds = jsonPathObj.get //get the first employee name:String empName = jsonPathObj.get 

Refer Spring Boot Rest Assured Example to understand how to use JsonPath to extract the specific object from the response.

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Best Coding Practices For Rest Api Design

JSON, Endpoints, Postman, CRUD, Curl, HTTP, Status Code, Request, Response, Authentication,

All these words are familiar to you if you are in backend development and you have worked on API . Being a developer you might have worked on some kind of APIs . Maybe a payment gateway API, Google Maps API, Sending Email APIs, or any other kind of APIs depending on the type of application and the requirements.

Many times it happens that developers read the documentation part of the API, implement it, but they do not focus on building a clean, understandable, and scalable architecture when they are implementing any kind of API in their application. These things impact a system a lot when the application grows with time.

Consider a scenario that you have built an application and now you need to expose the interface to the user. Do you really think that both of you will be at the same table? Do you think that they will understand the same thing that youre trying to depict in your system?

When youre building a Restful API it is important to design it properly to avoid any bug or issue in your application. You need to take care of the performance, security, and ease of use for API consumers. It is good to follow some good conventions to build an API that is clean, understandable, and easy to work with.

Summary Top 20 Rest Api Interview Questions

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Explain What Is Rest And Restful

REST represents REpresentational State Transfer it is a relatively new aspect of writing web API.

RESTFUL is referred for web services written by applying REST architectural concept are called RESTful services, it focuses on system resources and how state of resource should be transported over HTTP protocol to different clients written in different language. In RESTFUL web service HTTP methods like GET, POST, PUT and DELETE can be used to perform CRUD operations.

Define Messaging In Terms Of Restful Web Services

Messaging is the mode of communication between client and server for RESTful web services. An HTTP request from the client initiates an action at the server, and an HTTP response is sent back from the server to the client with a status code. It may also include the information requested. This is known as messaging.

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Ready To Succeed In Your Next Web Api Testing Interview

API testing interview questions can be unlimited regarding of the number of questions and area covered. Although the above answers might not fully be used in your interview, we do hope it somehow provides the solid understanding on Web API testing and gets you ready for the upcoming job and project related to API testing.

Wish you confidence and luck in your testing career! If you have any suggestions on this topic, please do not hesitate to add to here. We look forward to a better and more adequate list to all testers.

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Q: What Are The Ways And How To Validate The Response Of Rest Api In Rest Assured Ans:

Response is an interface available io.restassured.response package.This interface contains many methods, majority of which can be used to extract parts from the received response. Below are some method of response which we can use to validate the received response:

Response employeesResponse = RestAssured.given.request //validate the resonse using AssertAssert.assertEquals) 

Response employeesResponse = RestAssured.given.request //validate response using Assert and checking with response StatusLineAssert.assertEquals) 

Refer Spring Boot Rest Assured Example to understand how to extract and validate the response.

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Q: How To Deserialize A Response Json As List Of Pojo In Rest Assured Ans:

In below ways we can deserialize a response JSON as List of POJO in Rest assured:

List< Employee>  returnedEmployees = Arrays.asList.as) 

JsonPath jsonPath = RestAssured.given.when.get.then.assertThat.statusCode).assertThat.extract.body.jsonPath List< Employee>  Employees = jsonPath.getList 

What Does The Annotation @pathvariable Do

The URI template variables are bound to the handler method parameters of a controller using the @PathVariable annotation. Multiple @PathVariable can be used in the same method. In resource creation, the path variable plays a critical role. Spring MVC provides URL customization support for retrieval of data through the use of @PathVariable.

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Q: What Is The Best Way To Keep Sensitive Data Out Of The Log In Rest Assured

It is now available to blacklist headers using blacklistHeader method in REST Assured 4.2.0 ensuring that they are not displayed in the request or response log. One or more headers can be blacklisted. A blacklist is used to prevent sensitive data from being included in the log.

Set< String>  headers =newHashSet< String> headers.add headers.add given.baseUri.header.// blacklist headersconfig.blacklistHeaders))// blacklist multiple headers//config.logConfig.blacklistHeader)).log.all.when.get.then.assertThat.statusCode 

What Is The Architectural Style For Web Apis In Rest

A question like this tests basic knowledge and might introduce a longer line, more complex line of questioning about REST. If you’re a developer, your interview is likely to cover a wide range of technical concepts, so REST questions will likely only take up a portion of the interview and get progressively more advanced. If this is your first REST question, you can answer it by giving a small description of REST and then answering the question.

Example:”REST is a set of constraints that has to be applied for an application to be RESTful. The architecture has to have a few key characteristics. HTTP so that a client can communicate with the enterprise server. A formatting language specified as XML/JSON. An address to reach services in the form of Uniform Resource Identifier and communicate statelessly.”

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What Do You Mean By Rest Api

A software-to-software link known as an application programming interface enables communication and data sharing between otherwise independent programs. For example, a news website could use the Twitter API to discover pertinent tweets automatically and integrate them into news stories.

An API that adheres to REST principles is known as a REST API, sometimes known as a RESTful API. In a REST API, each piece of data is handled as a resource and given a distinct standard resource identity .

For instance, the Twitter API makes every tweet a retrievable resource that is available to clients. The Twitter API can be used by users to post tweets and carry out other website tasks.

Why Is Http Protocol Important For Rest

HTTP protocol is important for REST because it’s a way to communicate data between client and server. Without HTTP methods, requests and responds, and HTTP status codes, it would be difficult to build a REST API.

• Every HTTP request includes a method and a status code.
• The client-server interaction is based on requests and responses.

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What Are The Major Security Issues Faced By Web Services

Security is a major concern online. Since APIs are instrumental in allowing applications to interact with each other, its critical to understand the major security threats to them. Some of the major security issues faced by web services are:

• Coding Related: An improper code can leave an API vulnerable to attacks. For example, a function that can accept user input to access a resource can increase the likelihood of an attack.
• User Authentication: When the authentication is not managed properly, it creates a security issue.
• Injection Issues: Attackers can inject malicious code through an existing query. This is one of the major security issues.
• Deprecated API Management: Usually, several endpoints are exposed because of APIs and increase the risk of attack if the deprecated APIs are not managed properly.

Java Rest Api Interview Questions

• Difference between Get and Post call?
• How/why do we call Get and Post a call?
• Is it mandatory to send request data in JSON format only?
• How does API work?
• What is the difference between REST API and microservices?
• Why we do get parameter session and variable declaration in API?
• why do we use mocks or stubs?
• Difference between SOAP API and REST API?
• What is the difference between the patch and put method in RestApi?
• What is the difference between a REST and RESTful?
• What is REST ASSURED?
• How does caching work in microservices?
• What are the expectations the Technical panel sees for a tester from an API Automation perspective?
• Why do we do API Testing what is the advantage and where we can do API testing?

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What Exactly Is Uri

A computer network resource can be referred to using a URI or uniform resource identifier. It serves as a means of separating one resource from another. The sources might or might not be online.

Due to their standard structure, URIs make it simple to connect to even various types of resources. The location or name of the resource is included in URIs together with a string of characters.

The URI is made up of a path, scheme, query, and other elements but does not include the protocol.

Using a protocol, URLs are used to find resources on the internet or accessible through it.

How Do You Keep Rest Apis Secure

Answer: REST APIs do not employ as strict security measures as SOAP APIs, and therefore should not be used to send or retrieve sensitive information. However, good REST APIs still implement safety measures for secure and reliable data transfers.

• Authentication and authorization: All requests to the API should be authenticated and authorized. Authentication is the process of verifying the identity of the client, and authorization is confirming that the client has permission to access the requested resources.
• Validation: After authentication and authorization, requests still need to be scanned for potentially malicious code before the API gives access to its resources. Otherwise, a server will be vulnerable to an injection attack.
• Encryption:TLS/SSL encryption secures the connection between client and server and prevents attackers from intercepting requests and responses.
• Rate-limiting: Rate-limiting methods like quotas and throttling prevent brute-force attacks like DDoS that attempt to slow or crash the server.
• No sensitive information in URIs: Protected information should not be visible in the URI of a resource.

For more in-depth explanations, see our post on API security.

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Additional Behavioralquestions For Rest Api Development Interviews

Make sure to prepare for these REST API interview questions before your upcoming tech interview.

What Is The Use Of Forms In Django

Forms serve the purpose of receiving user inputs and using that data for logical operations on databases. Django supports form class to create HTML forms. It defines a form and how it works and appears.

Django’s forms handle the following parts:

• Prepares and restructures data to make it ready for rendering
• Creates HTML forms for the data
• Processes submitted forms and data from the client.

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What Are The Advantages And Disadvantages Of A Rest Api

Its important to know the pros and cons of a RESTful API.

Advantages include:

• Designed for high performance, portability, reliability, and scalability
• Client-server separation allows each to individually operate and scale
• Easy to test and adapt to various environments
• Easy to learn as it uses HTTP protocol
• Supports various data transfer technologies including JSON, XML, YAML, images, and more
• Uses less bandwidth than other methods, such as Simple Object Access Protocol technology

Disadvantages include:

• Doesnt enforce security practices
• HTTP method limits you to synchronous requests
• Due to statelessness, you might be unable to maintain state

Hackerrank Rest Api Questions Solutions

• What will you check first when a lot of failures in API automation?
• What will you do when the API structure changes?
• Which dependency is good to handle Json operations?
• How do you keep Json requests in the automation framework?
• Which of the following takes more time to script. Get or Post a call?
• Tell me your approach to automating an API that is under development
• Tell me a complex scenario you automated so far
• What will be your action, when a mandatory header which is passed in all the services becomes optional?

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