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Software application development: Mobile, cloud apps push APIs forward

Basics found in REST will help keep developers from being overwhelmed as they navigate software application development.

If 2013 was the year application program interfaces (APIs) moved to the forefront of IT project to-do lists, 2014 is going to be the year enterprises realize the value of leveraging them to unlock and monetize data. Mobile and cloud applications certainly are pushing software application development and APIs forward, but what will keep developers from being overwhelmed will be the basics, found in representational state transfer (REST) and standards that may begin emerging this year, according to experts.

"The common understanding of REST has diverged a little bit from the original architecture when it was coined 14 years ago, so the holistic understanding of what REST can be is often overlooked by architects and developers," said Marcin Warpechowski, head developer at Stockholm-based database technology company Starcounter AB. Most APIs aren't developed according to REST principles, but using the more holistic facets of REST allows developers to take advantage of its simplicity, he added.

Hypermedia enters the arena, building on REST

Hypermedia APIs that conform to the REST constraint HATEOAS (Hypermedia as the Engine of Application State) are rising to the surface as the Internet of Things (IoT), or objects and their representations that are in an Internet-like structure, move front and center, according to Matthew Bishop, senior architect at Vancouver-based Elastic Path Software. "It means that client applications can securely access enterprise data and perform authorized operations using only the hypermedia controls generated by the mediation layer," he said.

IT leaders beware

This is where REST chimes in, since IoT objects have less power, less processing ability and less capability for creating REST calls, leading to the simpler, stabler design of Level 3 REST, Bishop said. Since IoT isn't easily updatable, Level 3 REST jumps in as a way to create "versionless" hypermedia APIs that don't need changes, he added.

REST may not be everything with software application development

"Some people make the mistake that REST is the only thing," said Roberto Medrano, executive vice president at Los Angeles-based SOA Software. That doesn't mean REST isn't valuable to software application development, but like SOA services several years ago, it's now seeing a lot of usage. However, as new protocols and standards emerge, existing governance principles will extend to manage them, and REST will evolve with it, according to Medrano.

For example, REST may be edged out by Message Queuing Telemetry Transport for such things as mobile applications or WebSockets for real-time applications. "Those things are used in small places but will become more prevalent," Medrano said, particularly as health monitors and small specific devices continue to evolve. However, the principles of SOA will continue to apply to those, he added.

Smart developers and companies are the ones that will fully embrace hypermedia APIs in 2014 and beyond.
Matthew Bishopsenior architect, Elastic Path Software

Yet new protocols will also help drive the evolution of REST as developers create more industry-specific APIs, such as APIs for credit financing and loan applications, according to Medrano. The IoT is definitely driving these forward, but the main driver for new APIs is the way content is consumed, such as through mobile devices, he said.

"Mobile is just a huge part of driving public-facing APIs [and] APIs in general, even internally at larger enterprises," said Gregg Carrier, lead software engineer at Charlottesville, Va.-based WillowTree Apps Inc. Organizations are finding that they need new ways to present data, and the easiest way to do it is to take advantage of the devices in everyone's pockets by building standards-based, public-facing APIs, he said.

the cloud is also a factor for API growth in 2014 as a distribution and deployment mechanism. "It's fantastic in the sense that it enables more companies to expose data via APIs," Carrier said. The cloud will allow smaller organizations without the means to set up their own hosting environments to deploy and host their data and APIs, he said.

JSON developments jump into the fray

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New developments in the lightweight JavaScript Object Notation (JSON), including the JSON Patch and JSON Pointer standards that settled last year, will also become part of the API development toolkit, according to Warpechowski. These communicate changes to JSON representations without sending the entire resource, just the part that changed. Now that JSON Patch has become a Request for Comments, developers who want to send just partial changes have a standard to follow, rather than jerry-rigging their own, he said.

JSON Siren also works well with hypermedia APIs and allows developers to represent hyperlinks in JSON. Warpechowski expects JSON Siren will also gain traction in 2014 since JSON-based APIs are more RESTful. "Now you can define the relations between the resources in JSON, which was not possible or standard before," he said. "This may be a good trigger for other standards to build on JSON."

Ultimately, an increase in building single types of applications with new ways to create them -- specifically, with emerging standards and protocols -- will continue to drive APIs in 2014. REST will evolve as an architecture to accommodate IoT. However, as Bishop said, "the smart developers and companies are the ones that will fully embrace hypermedia APIs in 2014 and beyond."

About the author:
Christine Parizo is a freelance writer specializing in business and technology. She focuses on feature articles for a variety of technology and business-focused publications, as well as case studies and white papers for business-to-business technology companies. Prior to launching her freelance career, Parizo was an assistant news editor for SearchCRM.

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