Guide To API Development: How To Build An API?

API development is essential to embrace innovation, efficiency, and a more connected tech world. 

It helps with rapid development and innovation, improved user experience, enhanced scalability and flexibility, better collaboration and integration, increased revenue potential, and more.

Around 56% of enterprise giants find APIs helpful for creating better digital products and experiences. 

Whether you are a developer, business owner, or a user, API can benefit everyone, creating an interconnected digital ecosystem. 

How to build an API? 

This blog post will discuss the same with the API working, benefits, types, features, etc. 

Let’s get the ball rolling!

What Is An API?

API (Application Programming Interface) acts as a middleman between two apps (as discussed in the introduction), and it facilitates seamless communication and data exchange between them. 

Let’s take an example to get it better. 

Imagine Application 1: A weather app; Application 2: A weather service database.

The weather app can’t directly retrieve data from the weather service’s server. 

Here, the weather service offers an API to the weather app to establish communication with the server. 

Ahead, leveraging the power of API, the app can send a request and highlight your data location. 

Then, the API accesses the related weather data (humidity, temperature, etc.) and sends it to the app performing data exchange. 

Next, the app interprets data and showcases the weather forecast report on your phone. 

Above all, APIs help the applications with a well-structured way to request and receive details from each other, easing developers to create applications that use current data and functionalities with no need to start from scratch. 

How Does API Work? 

Thinking of API communication as a request and response between a server and a client will help with a better understanding. 

• Client: The app that submits the request;
• Server: Respond to the request. 
• API: A bridge between both edges. 

How do APIs Work – Look at an Example

When a user buys a product on an e-commerce website, the site may prompt the user to opt for a third-party system for online payment. 

Here, the APIs come into play to make the connection. 

• After purchasing, when the buyer clicks on the payment button, an API call is sent to access information, which is the request. It’s processed from an app to the web server via the API’s Uniform Resource Identifier (URI), incorporating headers, a request verb, and a request body (sometimes). 

• Post getting a valid request from the product webpage, the API calls to the web server external program, or 3rd-party payment system (in this case). 

• Then, the server responds to the API with the requested details. 

• In this case, the API performs data transfer to the starting requesting app, the product website. 

You can’t see anything on the user interface, which means that APIs perform data exchange within the computer or app, and the user finds the connection seamless as the outcome. 

Benefits Of API For Businesses 

The app design and development become easy with APIs, which simplifies the management integration of the existing ones. 

Besides, there are varied benefits of APIs, let’s check them out:

1. Paced Innovation

APIs are flexible, permitting companies to connect with new businesses and provide new services to the current market. 

Thus, companies can access new markets that can lead to digital transformation and boost returns. 

2. System Security

APIs keep the requesting application away from the infrastructure of the responding service and provide security layers between the two as they communicate. 

3. Enhanced Collaboration

Integrating enterprises into the app’s APIs allows smooth communication within them. So, companies can automate the workflows and enhance workplace collaboration, improving productivity and performance. 

4. Data Monetization

Most companies offer APIs with no extra cost, at least in the beginning, to create an audience base of developers around their brand and build connections with potential partners. 

If APIs offer access to digital assets, a business capitalizes on it by selling access, which is known as the API economy. 

5. User Security and Privacy

APIs offer extra security within a network. They hold the caliber to offer extra protection for personal users. When a site requests a user’s location, the user is free to allow or deny this request. 

These benefits of APIs are enough to underscore how useful it is to opt for them and catch up with increased system security and improved collaboration. 

Types Of Application Programming Interface (API)

Multiple APIs are available in the markets that have the potential to satisfy open and highly-customized development needs. Based on the scope of use of APIs, these can be classified into four types. This classification helps developers find an ideal product according to their development needs.

1. Private APIs

Internal APIs are also termed internal APIs, which can be used within an organization only. These are ideal for connecting all data and business systems. The best examples include APIs connecting payroll and other HR systems within an organization. 

The private APIs have no security needs, and hence, they come with weak authentication and authorization. The security levels of overall business systems are enough to manage these APIs that work internally only.

2. Partner APIs

As the same suggests, these APIs are for business-to-business interactions only. Hence, partner APIs are specific to authorized and specific developers only and are not available to all developers. The best use of partner APIs includes the APIs offering access to customer data to external CRM firms. Hence, these are authorized access with no external API use. All these APIs are available to license holders only. Compared to all APIs, partner APIs have high levels of authentication, security mechanisms, and authorization.

3. Public APIs

These APIs are open and, hence, can be used by any developer. Hence, many businesses looking to offer API for development purposes only use public APIs available to a wide audience. These APIs work on moderate authorization and authentication. Businesses can earn by monetizing their public APIs and can earn from per-call costs.

4. Composite APIs

These APIs are the combination of two or more types of APIs. This combination of APIs brings great improvement in functions and high levels of optimized performance. Composite APIs dedicatedly satisfy the exclusive requirements of multiple businesses that are not independently met by a single API.

Architectural Styles of Designing APIs

Architectural designs are the blueprints that tell how APIs need to be structured and how communication takes place between apps. These styles arrive with guidelines following which you can ensure efficient, easy, and well-organized API development. 

Some common architectural styles of designing APIs are:

1. SOAP (Simple Object Access Protocol)

A heavyweight and more structured approach, SOAP uses XM for communication and data. It sets strict rules for formatting and processing requests and responses. 

Pros:

• Secure data exchange
• Robust error handling
• Platform Independence

2. RPC API (Remote Procedure Call API)

RPC APIs directly call remote procedures on another system, as if you call a local function in your program. Usually, they harness the power of proprietary protocols for seamless communication specific to a platform or programming language.

Pros:

• Easy to understand
• Language-specific optimizations

3. REST (REpresentational State Transfer)

It’s a flexible, lightweight approach that utilizes current web standards, such as HTTP (Hypertext Transfer Protocol). It aims at resources (data entities) and opts for standard HTTP verbs (GET, PUT,  POST, DELETE) and conducts CRUD operations (Create, Update, Read, Delete) on those resources. 

Pros

• Handles high traffic
• Perform seamlessly across varied platforms and programming languages
• Adaptable to varied data formats and use cases.
• Easy to understand and implement

Terminologies, Specifications/Protocols Of API Development

Moving ahead, you should know you will meet new and relevant words that you find challenging to understand. Before you start with API development, let’s scan crucial terminologies and specifications of API development to grasp the knowledge efficiently.

1. API Key

These keys are required to request any API. API keys are linked to the user accounts. Without an API key, it cannot process the request, and the user gets an HTTP 403 error. API keys are used to define access levels or authentication to the allowed API user. Businesses use multiple API keys for different integrations.

2. Endpoint

As the name suggests, the ends of communication are endpoints. In API communication when these interact with one another, the touchpoints of the API interaction are endpoints. In API’s endpoints, the URL of the service or server is used. In other words, the point of API ending and resource lives are endpoints. As the main use of the endpoint is seamless integration, the performance of any API depends on its communication with API endpoints. 

3. JSON

It can be considered as the language used by two APIs to communicate with each other. JSON is machine-readable and human-readable, which makes it super easy to understand the data flow between APIs. Thus, it helps developers to understand the API that comes with no independent user interface. JSON makes it easy for APIs to understand requests and share responses. It includes a key that labels the data and the value of the data. An example of a JSON block is “serial number,” which indicates the exact serial number of the data line containing a specific number value.

4. GET

It is an HTTP request that asks for a specific resource from the server. GET requests help receive data without any changes. It is used to send any HTTP headers but can’t send data due to the absence of a message body. Hence, GET requests are widely used in APIs.

5. POST

The POST requests are used to send data to the API server to update or create different resources. All common HTML forms on the internet operate using POST requests only. It allows data to be sent as a package in separate communication using the processing script. Hence, the data sent through the POST request is not visible in the URL. Hence, offers security in data communication in APIs.

6. OAuth

It is the delegated authorization framework for APIs. It helps apps to obtain limited access to the user’s data without going away with the user’s passwords. Hence, OAuth eliminates the coupled operations of authorization and authentication. It supports multiple use cases with multiple device capabilities.

7. REST

Representational State Transfer, or REST, is one of the architectural styles that act as the groundwork for API communication. It is the set of constraints or architecture that defines the behavior of internet-scale distributed hypermedia systems.

8. SOAP

Simple Object Access Protocol (SOAP) is the messaging protocol specification for exchanging structured data to implement web services. It allows developers to initiate all processes running on multiple operating systems like Windows, Linux, and macOS and uses Extensible Markup Language (XML) to authenticate, authorize, and communicate. Hence, all communications remain independent of platforms and languages.

9. Latency

The API latency is the total time taken by any API system to respond to the call. It starts from the receipt of a request at the API gateway and goes up to when the first response is returned to the same user. The main cause of latency is the distance between the devices making requests and servers responding to them.

10. Rate-Limiting

It is the limit to the maximum number of calls that are allowed in a specific time interval. Hence, rate-limiting helps define the network traffic for any API. It prevents API throttling and hence optimizes the API efficiency.

11. API Throttling

It is the server-side response to the rate-limiting. It allows the API to control the resource consumption. Hence, API throttling is defined as preventing API traffic.

Tools For Developing An API

Varied tools are essential for proper designing, documentation, testing, and deployment throughout the API development cycle.

1. Apigee

It comes from tech giant Google, an API management provider that re-establishes an API-integrated approach. Apigee is used by multiple developers and entrepreneurs to lead digital transformation.

2. APIMatic and API Transformer

Both of these tools offer sophisticated automatic generation tools to create API code snippets and high-quality SDKs. APIMatic and API transformer further help transform the code snippets and SDKs into specific formats like API Blueprint, RAML, etc.

3. API Science

Not a common term, API science is a recipe for API development that provides best practices to design, create, and manage APIs to make them easily understandable. 

4. API Serverless Architecture

It fuses APIs with the power of serverless computing. Despite self-managing servers, your code runs on-demand to respond to API requests. It means you experience faster development, automatic scaling to manage traffic spikes, and lower costs. It’s a perfect pick for creating the latest, cost-effective APIs. 

5. API-Platform

An API platform is a software system that manages the complete API lifecycle. It includes API designing, development, documenting, deploying, and monitoring. It’s like a central hub for every API-relevant activity.

6. Auth0

A cloud platform that performs like a security guard for an app. It manages user authentication and authorization, allowing users to aim at crafting unique features. Also, it eases login, scales to attain requirements, and secures your apps.

7. ClearBlade

ClearBlade provides a platform for developing and managing the Internet of Things (IoT) APIs. The tools it offers connect devices, accumulate sensor data and control them remotely with APIs. Using ClearBlade APIs, developers can create apps that efficiently and securely interact with varied IoT devices.

8. GitHub

It is an open-source git repository service that offers dedicated code management. GitHub is useful for managing code files, version controls, commenting; pull requests, etc., across a group and helps save codes in private repositories.

9. Postman

Leveraging Postman, users can design, test, and document APIs. You can acknowledge it as a one-stop shop for creating and interacting with APIs. Besides, you can opt for Postman to create requests, check responses, and collaborate with others to develop well-tested and powerful APIs. 

10. Swagger

It’s a suite of tools that help design, document, and share API. Swagger allows defining what your API performs, how to harness its power, and what data it accepts. This makes learning and integrating with your API easy for other developers. 

Utilizing the capabilities of these tools, you can seamlessly build an API that benefits your business.

Must-Have Features Of An Efficient API

APIs are found in almost every web or mobile application. Hence, it is easy to get confused when finding or designing one that satisfies your requirements. Below is the set of must-to-have features for any efficient API

1. Modification timestamps/Search by criteria

Ideally considered as one of the must-have features, any API is incomplete without modification timestamps or search by criteria. It allows changes like updating, editing, or sharing after the first and initial data synchronization. Further, APIs should enable data-based user search.

2. Pagination

It is another important feature that helps get a glimpse of data change and informs about the pending number of data pages. It helps API to determine the right amounts of data to display in one go and its frequency.

3. Sorting

It enables data sorting based on different features like time, ensuring that the end-user can receive all data pages one by one.

4. JSON Support/ REST

JSON support makes it easy for the developers to parse the API to any other language due to its resemblance to the majority of languages. REST APIs are well-known for being lightweight, stateless, and offering retry features in mobile data upload.

5. Authorization and Authentication

Authentication like OAuth, OAuth2, and JWT. Authorization checks the permission of the user for access, while authentication simply verifies the user’s identity.

6. Cache

It is necessary to retrieve resources at a quick speed. Multiple tools enable caching in APIs that further reduce the request costs as data is ready for consumption in the in-memory database.

7. Wrappers

These are the language-specific packages or containers in APIs. It can call multiple APIs without user interaction and, hence, effectively combines different sets of APIs.

8. HATEOAS

It is one of the popular modules of REST application architecture and stands for “Hypermedia As The Engine Of Application State.” Hypermedia stands for videos, images, text, etc. It helps users to interact with REST API using dynamic responses from the server.

9. Error handling

It is crucial to facilitate the debugging process and help understand the type of error, i.e., server or client error. There are multiple methods, like the use of well-known standards, the right number of errors, causes, segregating domains, etc., that can be used.

10. Validation

It stands for verifying the data’s correctness. It can be client-side or server validation.

11. Testing

It is crucial to test APIs using tools like SoapUI, Postman, and JMeter. Hence, helps meet the performance, functionality, reliability, and security of APIs.

12. RESTful Design

A widely-known architectural style, RESTful design makes it easy for developers to understand and use APIs. It utilizes HTTP verbs for data access, deletion, and updates. 

13. Versioning

As you develop an API, you may make some changes to it. With versioning, you can maintain varied versions simultaneously and ensure current integrations stay unaffected while you provide updates for new users. 

14. Webhooks

Such real-time notification permits your API to push updates to other apps whenever an action is performed. This syncs the integrations and allows automated workflows. 

15. Documentation

Your API’s user manual is clear and complete documentation that explains how the API works, its usage, what data it takes/returns, and the examples. Best documentation saves developers time and diminishes integration issues. 

16. Rate Limiting

This avoids issues by regulating how users usually access your API. It safeguards your servers from the pressure and ensures a flawless experience for everyone. 

17. Monitoring and Analytics

With this feature, you can track API usage, error rates, and performance metrics that assist in identifying and fixing issues rapidly. Besides, it offers insights into how developers use API, permitting them to make informed, data-driven improvements. 

By incorporating these features in your API, you can build a secure, simple, and easy-to-use API. 

How To Start Developing An API?

Before we know how to build an API, let’s first learn that it’s the process of minutes to even months based on the API’s complexity and tools used. 

Now, let’s uncover the steps following to build an API. 

1. Define API’s Objective

Start with defining your objective for creating an API. You should determine the data or functionality you want to reveal using your API. Overall, you should define API’s core value proposition. 

2. Choose the Best Fit Technology

Go for the framework and programming language that best suits your business requirements. Popular picks are Python, Node.js, and Ruby on Rails.

3. Design API’s Endpoints

Finalize the URLs and methods that can let you interact with your API to access data. Thus, you can maintain clarity and consistency for users trying to interact with your API. 

4. Implement the Logic

First, write the code that strengthens your API. It will manage the incoming requests, process data, and give responses. 

5. Test the API

Test your API thoroughly, ensuring it performs as required. Once you are sure, make it all set to deploy to a server environment from which developers can access and integrate. 

6. Document Your API

Now, craft clear documentation of your API so that developers can see how to use it.  This incorporates details on data models, endpoints, error codes, and authentication methods.

7. Secure and Deploy the API

Implement authorization and authentication mechanisms to control your API access and safeguard sensitive data. Ahead, select a hosting solution and allow developers to access your API. 

8. Monitor and Maintain

Observe your API’s performance and be set to locate issues, make improvements, and update API documentation per the evolving needs and user feedback. 

This is how you can develop an API for your business, suit your needs, and make changes ahead according to user feedback and other technical transformations. 

What Is The Cost of Building an API? 

Usually, the cost of building an API ranges between $5,000 and $20,000, and the figures may change depending on a few factors, as we have discussed below:

1. Features

Implementing features, such as advanced caching mechanisms, robust security measures, and real-time functionalities, such as webhooks, that elevate development cost and time. 

2. Complexity

With the increasing functionalities and data models of APIs, the complexity increases, affecting the cost of API development. 

3. Deployment and Hosting

The cost of cloud platforms or servers required to host API impacts the overall expenses. If your API expects high traffic, going for scalable cloud-based solutions may cost you less in the long run. 

4. Backend Integration

Integrating your API with current backend systems may influence development cost and time. Existing APIs or perfectly documented systems are more straightforward to incorporate than legacy systems, demanding tailored data access solutions. 

5. Deployment and Hosting

You would need the cloud platforms and servers to host your API, and these affect the overall expenses. You can opt for clear documentation here that can clear up developers’ minds and integration time while testing, which assists in avoiding bugs that may demand fixes later. 

Consider these factors and plan the API development process properly while creating a cost-effective API solution that meets your unique needs. 

Best Practices For Building The Right API 

Well-crafted APIs live longer as they can be improved despite being useless with the changing user requirements. 

Go for the best practices below to attain your API objective and fulfill users’ needs. 

1. Hold the Simplicity

Aim to develop a simple and straightforward API that’s easy to use. Consider using an SDK that can diminish authentication complexity and make the authentication process flawless for developers. 

2. Performance

Use filtering and pagination to degrade the load on server responses and enhance API performance. Besides, you can maximize caching usage to boost performance for data that stays the same for a long time. 

3. Authentication and Authorization

You should conduct user verification before requests and check access levels to safeguard APIs from malicious attacks. 

4. TLS Encryption

Opt for HTTPS or TLS encryption to let data stay well-protected while it passes between your server. Also, encrypted communication between the API endpoint and API consumer is essential for sensitive HTTP traffic. 

5. Versioning

While you build an API, you must remember to versioning your API. It permits easy maintenance of emerging changes by allowing you to create a new version for crucial changes while keeping the older one intact. 

6. Error Handling

When an error occurs, this practice provides details to the user, like an error alert or status code sent to the developer, helping them debug the code. 

You can follow these practices to build an easy-to-use, flexible, secure, and reliable API.

Build Your API With EmizenTech

Choosing a company for API development is essential for meeting customer requirements and achieving unique business objectives. 

While hunting to partner with a company, you should go for EmizenTech, a leading software development company offering global clients custom API development services. 

EmizenTech delivers well-documented and safe APIs for their apps to easily connect and collaborate with customers and partner vendors and drive new revenues. 

Key Highlights of EmizenTech

• Experienced in building APIs from scratch
• Teams of skilled developers 
• Clear communication
• Agile development
• Project management
• Aim at scalability and security
• Proven track record

Conclusion

Building an API for your business can benefit your customers and organization. It’s a win-win situation here, as the customers can reap the advantages of extra functionality, new possibilities, convenience, and efficiency. On the other edge, businesses can experience boosted revenue streams, enhanced scalability, valuable customer insights, and increased brand awareness and reach. 

Opt for API development services from a reliable software development company and build an API per your requirements. 

Connect with EmizenTech to build an API that seamlessly integrates, grows your revenue, and enhances your customers’ and partners’ experiences. 

Frequently Asked Questions About API Development