RESTful API Design: Best Practices and Approach

The API best practices start with their structure, type, how to send and receive the data, security, performance, scaling, etc.

RESTful API Design: Best Practices and Approach
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In the first article, we learned some basics of RESTful API design, its common use cases, and its benefits. Now we’ll talk about the best practices and how to identify a good API design approach.

Best Practices while Designing and Developing RESTful APIs

Here are some of the key best practices you should follow when you start thinking about designing and developing REST APIs. It should start with the structure, type, how to send and receive the data, security, performance, scaling, etc.

Transfer Data with JSON

JSON is the standard for transferring data. Whether you send a request or receive a response, a REST API should accept JSON. It is not difficult in this modern age as most networked technologies use it.

For instance, JavaScript comes integrated with methods to encode and decode JSON. It allows via an HTTP client or Fetches API. Regardless of the method, the server libraries do not have much work to decode JSON.

There are also some other ways for data transfer, like XML. While it is fine for developers, it’s not easy for the client. That is due to the difficult data manipulation in XML. It takes comparatively more time for the simple transfer process. Also, it is not supported by many frameworks.

On the other hand, JSON allows direct transfer on the client side. Plus, it is compatible widely with almost every framework. That is why it is usually the preferred choice.  It is a simple task with many benefits; all you have to do is set the “Content-Type” to “application/json.”

Use Nouns Instead Of Verbs in URLs

Using verbs at the end makes the URL difficult to read. Nouns describe them better. This way, a URL should be clean and easily used in web applications.

Having a long URL has many downsides. For instance, it is tricky to read and can cause many mistakes while recording. Nouns make the job easier by keeping it short. You can also use both singular and plural terms.

Plus, they are self-explanatory. A developer can understand the resource just by looking at the URL.

Use HTTP Methods

Each resource has several methods that can be operated to work with the data of an API. REST APIs use HTTP methods that are well defined. They represent the unique actions of a resource.

HTTP Methods define the CRUD operations of a resource. The methods mentioned above, including GET, POST, PUT, and DELETE, are used for the definition.

This is also why keeping verbs away from a URL is good. As these operations are also verbs, having a noun can make it more readable.

Logical Nesting

Designing endpoints can be complicated as it contains a lot of information. Having too many of them at the same time can confuse them. That is why the best idea is to group similar ones.

This simple practice keeps the data structure. Moreover, it can be easier for a developer to work with it.

Logical Nesting can be used again and again. So, to maintain readability, consider returning the URL to resources.

Deal with Errors

An error is common when designing APIs. However, its handling is a real art. To avoid errors, identifying the problem is the most important part. You can find this with the error code.

Here are all the common HTTP error codes and the reasons why they occur:
400 Bad Request: Input validation failed on the client side.
401 Unauthorized: The user is not authorized to access that resource.
403 Forbidden: The user is authenticated but not permitted to access a resource.
404 Not Found: The resource is not found or does not exist.
500 Internal Server Error: Error in the server.
502 Bad Gateway: An invalid response from the server.
503 Service Unavailable: Something Unexpected, like an overload or system failure, occurred on the server-side.

Once you identify the error, you can quickly throw it.

Improving Security

The data between the client and server is private. Hence, using good security measures is important. You should always consider SSL/TLS when designing a RESTful API.

Usually, people think these certificates are harder to load. Well, it’s not. And surprisingly, the cost is also quite low or free.

However, they offer a variety of benefits. The most important one is data authorization. For instance, a normal user level should not have access to a higher level of data.

Using SSL/TLS can allow you to prevent such mistakes. There are no reasons why you should not use stronger security in your REST APIs.

Maintain Cache Data

Maintaining data in the cache is a good practice. It allows fetching data faster. However, when there is too much data stored in it, that’s when problems arise. Users face many issues while debugging or accessing data.

Luckily, there are various solutions, such as in-memory caching. It allows us to control how the data will be stored in the cache. You can decide what stays and remove the outdated data to save space and make the work quicker.

Allow Sorting and Filtering

Needless to say, there is a large database working behind a REST API. Sometimes, they can get way larger, which makes the transfer slow. Therefore, you will also face difficulties in returning all the data simultaneously.

With filtering and sorting, you can drastically improve an API's performance. It allows you to return a specific number of data at a time. They reduce the usage of server resources so that more data can be stored in a manageable form.

Characteristics of a Good RESTful API

Once you follow these practices, you can make better RESTful APIs. But how to determine if it is a good one? Well, it’s quite easy.

Here are some characteristics of a good REST API:

  • Easy-to-read: A well-documented API straightforward method will have more readability.
  • Short URLs: As mentioned earlier, having a URL that uses nouns instead of verbs is better. It improves readability and prevents errors.
  • Well-Defined HTTP: An HTTP that defines proper operations is a MUST if you want a good RESTful API.
  • Error Handling: Errors can occur. However, the most important part is to fix them carefully. A good API involves a better approach to error handling.
  • HTTP Status Code: The HTTP status code should be expressive so that it is clear for both developers and clients.
  • Tighter security: Since the data shared between a client and server is private; protection should be your priority. Well-made REST APIs have all the essential security features.
  • Allow filtering results: Sorting and filtering results help you access the desired data faster. Hence, including this will help you save time as well as effort.
  • Log activity: Logging activity regularly of an API helps in future operations. That is why most developers adopt this technique.

If your RESTful API has these traits above, you are on the right track. However, you can take additional steps, such as limit rates, choosing between XML and JSON, track version, etc. All of these will help you in designing better REST APIs.

Conclusion

This article will help you with some key elements of the best practices of RESTful API. From what it is and how to use it to what are the best practices for designing it, it has covered all relevant topics.

Learning the essential and advanced aspects of the architecture will help you understand and develop better REST APIs.