Application program interface (API) is a set of protocols utilized for building software applications. This directs how the components of software interact with one another and are very useful as they make it easier to develop the program and put all the units together. More recently Hypermedia APIs have become the latest hype, scaling better and promoting decoupling and encapsulation easily along with the myriad of advantages these things bring.
REST (Representational state transfer) is a popular architectural approach to communications that currently utilized in the development of web software. REST’s lighter communication between producer and consumer makes it a well-liked system for cloud-based APIs, especially those provided by Google, Mircosoft etc. Running over the HTTP (hypertext transfer protocol, this architecture has several components, one of the most important being able to control a cache. REST APIs operate in a simple manner, by picking up a base protocol like HTTP and model the resources with a URI. You can then map actions into HTTP methods. However, hypermedia augments this procedure by simultaneous presentation of information and control hence poses as a pivotal constraint of the web and as an extension of REST.
So what is Hypermedia control?
As the digital world exceeds in complexity, more and more people want different components of a system all within a single application, to be able to easily interact with one another clearly. This cross-linguistic data exchange is what APIs have always been evolved to do, however, languages used to code individual software applications do not correspond nicely with each other.
Hypermedia that is hyperlinked can circumvent this need and can cause applications to stay interconnected and communicate easily. Hypermedia APIs is a more evolved and phenomenal way of creating APIs by using the universally used and understood hyperlinks.
This hypermedia functionality can embed links into associated resources in order to describe the action it will perform. This allows end users to carry out the actions that have been prescribed in the resource.
Current situation of web caches:
Due to the dynamic nature of web application, a lot of data is required to be stored. With every new request HTTP, caching is needed. With this caching, you cache the full output of the page requested, bypassing your application entirely on succeeding requests. While this is the current situation of web caches, it isn’t always possible for highly dynamic sites, which can only use the power of HTTP caching on fragments on these sites.
Caching with Hypermedia APIs:
Of the major issues with APIs and web-based architecture on a network is that optimum performance is acquired when the network is not in use, as this is the dawdling part of any application. Hypermedia APIs however, allow a greater caching of data on the browser cache through two ways, either a content delivery network or through a proxy on the server. This altogether reduces dependency on the network server infrastructure, hence increased speed considerably.
In addition, there is also a possibility of remote procedure call (RPC) with hypermedia APIs, where dynamic elements can be edge cached. In certain popular websites, this allows the trendy products or articles to be updated frequently along with the comments, opening a more interactive website.
One of the keys to successful Hypermedia API is its use of caching such as local caches and Etags. Moreover, in large systems cache invalidation can prove to even more costly than not caching at all. However, through careful designing of hypermedia resources, you can easily enable your system to depend on natural behaviors that are built into HTTP protocols.
Other benefits of Hypermedia APIs:
There are other benefits of Hypermedia APIs as well. These can enable applications to browse an API from the root or any resource, acting in a way that web works with hyperlinks. This needs API federation, where media APIs are interlinked with content API.
Moreover, it allows for more flexible and evolvable systems, as URIs remain persistent or unchanged, all configurations are done at the API root. If under any circumstance, the API is faulty, no damage will be suffered by the URL infrastructure and hence, this proves to be very cost effective.
In addition, Hypermedia APIs are also extensible. This means that more links and forms can be added without the fear of API breakage. These will also simply be ignored if they are not supported by the application of the client. Hence, validation and guidance of client are ensured.
Hypermedia APIs are simple and enable scalability from small to large single-page apps. They also enable standardization when API calls and made and the information if returned. The various links and forms are affordances in the hypermedia infrastructure and can be directed after the validation from the client side. While this advantage is still in research phase, it can prove to be very beneficial for certain businesses.
Another subtle advantage of hypermedia APIs over traditional APIs without hyperlinks is that in the latter you can only expose information that the client has requested, not caring what it is being utilized for. In a Hypermedia API, you are conscious of the workflow and can actively guide the client by providing links. This creates a superb communication between clients and server developers.
Limitations of hypermedia APIs:
Despite the obvious benefits, Hypermedia APIs still have certain drawbacks; however, these are just certain barriers that have to be climbed to allow for the adoption of this wonderful technology.
One of the most critical arguments against Hypermedia APIs is that the payload is higher for serialization of JSON, unlike thrift objects. However, overall if API actions are taken copiously, less data needs to be transported, so procedures like call sessions might not increase by such a high amount.
Future of Hypermedia APIs:
As systems become even more intricate, the need for universal language among diverse systems will be needed. Hypermedia, despite its limitations, will be the panacea in overcoming such communication gaps, especially in areas where Big Data and caching is concerned. Hypermedia is powerful and its full potential has yet not been discovered. It might even someday leave today’s REST and HTTP methods behind, relying solely on its ability to link through the common protocol, unorganized distributed data. How it completes this task only time will tell.
Interested in API strategy, architecture, and design. Working to improve the quality and usability of information on the Web. CTO @OrfiumMusic