Top IBM API Connect Interview Questions and Answers

Q1. What is IBM API connect?

Ans

IBM API Connect is a complete, intuitive and scalable API platform that lets you create, expose, manage and monetize APIs across clouds. This means you and your customers can power digital applications and spur innovation. IBM API Connect is also available with other capabilities as an.

Q2. Why use IBM API connect?

Ans

IBM API Connect has two main focuses: the first is providing best in class API Management tooling, and the second is having a cloud native solution. This allows users to create, manage, and secure applications that are deployed across a variety of on-premises and cloud environments

Q3. Benefits of IBM API Connect?

Ans

• Securely unlock assets. Securely expose existing business services via APIs to new mobile, IoT and web applications.
• Drive innovation. Attract and engage developers through API socialisation with enterprise governance built-in.
• Gain insights.

Q4. What is API in IBM API connect?

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IBM API Connect is an integrated API management offering, where all of the steps in the API lifecycle, and the actions that surround it, are performed within the offering. 

Q5. What is the difference between API Connect and App Connect?

Ans

The IBM API Connect and IBM App Connect available on IBM Cloud is used to implement the functionality. API Connect is used to provide OAuth based authorization security to microservices, and App Connect Enterprise for easier and seamless integration of APIs (with zero code) for a business user.

Q6. What are the common protocol used in API testing?

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• HTTP.
• JSON-RPC.
• REST.
• SOAP.
• JMS.
• UDDI.
• XML-RPC.

Q7. What is API testing?

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API testing is a type of software testing that analyzes an application program interface (API) to verify it fulfills its expected functionality, security, performance and reliability.

Q8. How do you build an API?

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1. Start with your goals and intended users.
2. Design the API architecture.
3. Develop your API.
4. Test your API.
5. Monitor your API and iterate on feedback.

Q9. What is a REST API vs API?

Ans

The primary goal of API is to standardize data exchange between web services. Depending on the type of API, the choice of protocol changes. On the other hand, REST API is an architectural style for building web services that interact via an HTTP protocol.

Q10. What is REST API testing?

Ans

REST API testing is an open-source automation technique to test RESTful APIs for web apps. It is commonly used for testing JSON and XML based web apps. It is compatible with all methods: GET, PUT, POST, PATCH and DELETE. REST is a Java library.

Q11. Name the different methods of performing an Input Injection?

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1. Simulation using Low-level Input
2. Robotic simulation
3. Direct method Invocation
4. Device Driver simulation
5. Accessibility interface invocation.

Q12. Why do clients need an API integration strategy?

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Setting up an API strategy can promote innovation, collaboration, and improve customer service. Organizations that fail to integrate all their different IT systems together and leverage the power of APIs will watch themselves lose market share to those who do.

Q13. What are the core capabilities of API connect?

Ans

The IBM API Connect solution provides an infrastructure, tools, and facilities that allows users to create, manage, and stage APIs. The ability to perform tasks in the IBM API Connect user interfaces is controlled through user roles, and the permissions that are assigned to those roles

Q14. How do you publish API in IBM API connect? 

Ans

1. In the API Designer, click Publish then click Add and Manage Targets.
2. Click Add a different target. You'll see the Sign in to IBM API Connect dialog.
3. Enter your API Connect host address, Username, and Password. Click Sign in. You'll see the Select an organization and catalog dialog.
4. Select the desired organization, and select the Sandbox Catalog.
5. Click Next. You'll see the Select an App dialog. Click the desired app, and then click Save.
6. In the API Designer, click Publish again.
7. In the drop-down selection, under Other Orgs, click the target you just created. 
8. Select Publish application and Stage or publish products, then select Select specific products. Select acme-bank, and then click Publish.

Q15. How create API in IBM API connect?

Ans

1. Create a folder to hold your API and Product definitions, and change to that folder in a command window.
2. Change directories to your LoopBack project and enter the following command: apic edit 
3. Log in to APIConnect Designer with the appropriate method.
4. Click Add > New API.
5. Enter the appropriate information to create a REST API definition.
   1. In the Title field, enter Branches.
   2. The Name and Base Path fields autopopulate with the terms branches and /branches respectively.
   3. Leave the Version field at 1.0.0.
   4. Leave the default Additional properties as they are.
6. You do not add a product at this time, click Create API.
7. If the API Editor help screen appears, click the sentence Learn more about composing APIs, or click Got it! to access the main screen immediately.
8. In the side bar, click Lifecycle to display the Lifecycle panel.
9. In the side bar, click Security Definitions to display the Security Definitions panel. 
10. In the side bar, select Paths to display the Paths panel. Create a new path by clicking the Add Path icon .
11. In the Path field, replace the default path segment with /details. When an operation is called, this path segment is appended to the URL of your API.
12. By default, a single GET operation is already in your Path. Click the GET button to expand the setting dialog.
13. For the operation, provide a summary and a description as in the following table.

    Table 1. Operation definition values

    Field	Value
    Summary	Branch details
    Description	Retrieve details of the current branches of BankA

14. In the side bar, click Definitions to display the Definitions panel. Add a Definition by clicking the Add Definition icon .
15. Expand your new definition by clicking new-definition-1. For the Name field, enter address, and a Description of the format of the address object.
16. Using the same Definitions panel, configure the Properties definition according to the following table. Edit the default property and then create new properties by clicking Add Property and editing the default values.

    Table 2. Properties

    Property Name	Description	Type	Example
    street1	The first line of the address	string	4660 La Jolla Village Drive
    street2	The second line of the address	string	Suite 300
    city	The city of the address	string	San Diego
    state	The state of the address	string	CA
    zip_code	The zip code of the address	string	92122

17. Create a second definition by clicking the Add icon in the Definitions panel.
18. Name the definition branch and, in the Description field, enter The format of the branch field.
19. Configure the branch definition to have the properties listed in the following table by creating new properties and editing the default property. Create new properties by clicking Add Property.

    Table 3. Properties

    Property Name	Description	Type	Example
    address	The address of the branch	address
    type	The type of branch	string	atm
    id	The ID of the branch	string	9d72ece0-7e7b-11e5-9038-55f9f9c08c06

20. In the side bar, select Paths to display the Paths panel. For the /details Path, click GET to expand the available settings. Include the branch definition in the GET operation Status Code 200 response by clicking the Schema field and selecting branch from the drop-down list.
21. In the submenu navigation bar, click the Assemble tab to open the assemble view.
22. Access the invoke policy property sheet by clicking the invoke label.
23. Populate the Title, Description, and URL fields according to the following table. When called, your API now invokes the existing Branches API and uses its response. In this tutorial, no transformations are applied to the response of this API and so the entirety of the response is returned to the caller. You can see this response at https://apictutorials.mybluemix.net/branches.

    Table 4. invoke fields

    Field	Value
    Title	Branches Invoke
    Description	Invoke an API to retrieve the status of all branches in the BankA system
    URL	https://apictutorials.mybluemix.net/branches

24. Click the Save icon to save your changes.
25. Click the Source tab to view the OpenAPI (Swagger 2.0) definition of your API. All the configuration you have performed is included in this definition, either as part of the standard OpenAPI (Swagger 2.0) schema, or as part of the extension.

Q16. What are the tools used for documentation?

Ans

Description: Small description about what a function does

Syntax: Syntax about the parameter of the code, the sequence in which they occur, required and optional elements etc.

Parameters: Functions parameters

Error Messages: Syntax of error messages

Example Code: Small snippet of code

Related Links: Related functions

Q17. Explain The Caching Mechanism?

Ans

Q18. Write the procedure or the modules of creating an API in a stepwise manner?

Ans

• Creation
• Testing
• Deployment
• Debugging
• Clustering
• Scaling
• Monitoring
• Management and administration

Q19. What types of Bugs will API testing find?

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• Stress
• Reliability
• Security
• Unused flags
• not implemented errors
• Inconsistent error handling
• Performance
• Multi-threading issues
• Improper errors.

Q20. What are the common tests performed on API’s?

Ans

• Verification of the API whether it is updating any data structure
• Verify if the API does not return anything
• Based on input conditions, returned values from the API’s are checked
• Verification of the API whether it triggers some other event or calls another API.

Q21. Mention what the main areas to be taken into consideration while writing an API document?

Ans

• source of the content
• Document plan or sketch
• Delivery layout
• Information required for each function in the document
• Automatic document creation programs.

Q22. What are the main challenges of API testing?

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• Parameter Selection
• Parameter Combination
• Call sequencing.

Q23. Mention what are the different application integration styles?

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• Shared database
• Batch file transfer
• Invoking remote procedure (RPC)Swapping asynchronous messages over a message oriented middle-ware (MOM)

Q24. Explain what are the principles of API test design?

Ans

Setup: Create objects, start services, initialize data etc

Execution: Steps to exercise API or scenario, also logging

Verification: Oracles to evaluate execution outcome

Reporting: Pass, failed or blocked

Clean up: Pre-test state

Q25. What are REST principles?

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• Contract first approach
• Uniform Resource identifiers.
• Statelessness.
• Client-Server model.
• Layered architecture.

Q26. What is the REST paradigm?

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Representational state transfer (REST) is a software architectural style that was created to guide the design and development of the architecture for the World Wide Web. REST defines a set of constraints for how the architecture of an Internet-scale distributed hypermedia system, such as the Web, should behave.