Anyone who has had to manage APIs for any length of time will at least have heard about REST. It is a design principle for developing APIs that can be used for creating APIs that result in a smoother experience for everyone involved – the developers of APIs, the app developers, the end customers, etc. This article will discuss all one needs to know about the REST design best practices but first one must understand the basics of APIs. ‘API’ is the abbreviated form for ‘Application Program Interface’.
To easily understand an API, one must compare it to an app – which provides an interface in which an end-user is interacting with the web, data, or service. An API, on the other hand, is meant to let programmers develop programs or apps that will interact with the base program or service. Thus it won’t be a person interacting with the program or data but another program.
To ensure the best flow of data through API, it must be design using REST architectural principles. The term ‘REST’ is an abbreviated form for ‘Representational State Transfer. The implementation is done by following a few core principles and can improve the usefulness of API significantly. The following are some of the key REST best practices:
Use names – not actions to name endpoints
The first and one of the most important design practices that can be recommend is to avoid using actions or verbs while naming various endpoints. That is important because the world of the internet is such that several commonly used verbs such as create, copy, delete, etc. are already use or may have a dedicated interpretation. It is thus simply easier not to risk naming the endpoints with action words.
Use plural nouns for collections
A simple principle is to use plural nouns wherever there is a collection of items – and thus simply saying ‘post’ in URL may be a bad practice when one has multiple posts. The word ‘posts’ will signify that there are other posts in the list apart from the one on screen.
Know status codes and don’t be shy about using them
Anyone who has surfed the internet regularly must sooner or later come across an ‘error 404’ – which may come with added comment ‘Page not found. ‘404’ or ‘resource not found’ is one of many HTTP status codes, some others include a Bad server error (500) or the ‘resource moved permanently. Such codes tell the user exactly what is going on. That information is doubly useful when using APIs. Since the end-user of API is different from its actual developer, it is important to communicate the present status of things – and that is best done through status codes.
Nest the endpoints
It is best to provide the proper nesting for the endpoints but not too much. Adequate nesting is both informative and can smoothen the fetching of information. However, the nesting should be no more than three levels as it will affect the readability and make the who thing far less beautiful and elegant. That limitation also reemphasizes the importance of choosing the various layers of the nest important. Thus if more than one writer is writing more than one post, including the name of the author as a separate layer from the post name can be helpful. But not if there is only one author or every post has a unique author.
S for Security
One of the most important REST design practices these days is security especially. As the public is growing increasingly more conscious of data privacy and data security. Anyone who surfs the internet regularly must have noticed that there are HTTP and HTTPS pages on the internet. That ‘S’ in the end stands for security. The browsers like Chrome will warn the visitor not to share information on a page that is mere ‘HTTP’ and not ‘HTTPS’. That ‘S’ is gain by implementing SSL. SSL stands for secure socket layer. When it comes to APIs, this security layer is critical for security against several kinds of malicious attacks and can not be ignore while preparing an API.
Use JSON for data transfer
JSON has become the industry standard for transferring and receiving data. It is a good REST design practice to always use it wherever possible for transferring data. It is now possible to manipulate JSON data in most programming languages.
Always define content-type
The ‘content type’ in the application header should be clearly define whatever format may be used to transfer data. In the case of JSON, which is recommend above, it should be set to ‘express.json( ).
Plan for the larger collection of data
When designing APIs, it is always a smart strategy to assume there will be large databases unless one is sure it won’t be the case. Now large databases can make processing of requests for the same go slower – however, one can change this by planning. Providing users simple tools such as filters and sorting can help them limit their search. And the server too will have to serve only a much smaller part of the collection. One can further limit the number of results served up with each request by using pagination.
Handing multiple versions with care
Unless necessary, one should not force an update of API on one’s clients. That means that an enterprise must handle several security patches. An important practice is to use semantic versioning – this method uses 3 different numbers serrated by period (.) to show the version number. The first of these versions show a major new version (and any new version that forces users to update their API should preferably be a big one). The middle one shows a minor update whereas the last number only shows a patch update.
The last and yet one of the most important REST design best practice is to write everything down and provide thorough documentation. About everything and anything in the API; even if those things may seem obvious to one.
The Bottom Line
One can easily wrap up the above discussion by concluding that REST design best practices should be follow everywhere. A REST API mock should be request so that one can envision the working of API.