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JSON Replacing XML for API Responses

By on May 25, 2011

ProgrammableWeb.com has detected an interesting trend in application program interfaces (APIs). The last few years have witnessed a significant trend toward only supporting JavaScript Object Notation (JSON) responses to requests. This means the classic API response format, XML, is being dropped completely by an increasing number of API developers. According to their figures, fully 20% of the APIs that have been released so far this year support only a JSON response format.

Why? For the same reason why SOAP was widely dropped in favor of RESTful requests — simplicity and ease of use. Most users of APIs are using them within a user interface environment, where Javascript rules. So the option to have an API response sent back as a JSON hash has immediate benefits, perhaps the largest of which is not having to parse the XML into a useable array.

The consequences of this seem clear — if you are a UI developer Javascript skills are essential. XML skills? Maybe not so much. Sure, there are still plenty of APIs that return XML, but as ProgrammableWeb.com has discovered, a smaller number of them each year. It may not be long before the vast majority of APIs you want to work with support JSON — any many of them to the exclusion of any other response format.

Thanks to @jafurtado for tweeting notice of the ProgrammableWeb.com post.

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Filed Under: Roy Tennant: Digital Libraries
Roy Tennant About Roy Tennant

Roy Tennant is a Senior Program Officer for OCLC Research. He is the owner of the Web4Lib and XML4Lib electronic discussions, and the creator and editor of Current Cites, a current awareness newsletter published every month since 1990. His books include "Technology in Libraries: Essays in Honor of Anne Grodzins Lipow" (2008), "Managing the Digital Library" (2004), "XML in Libraries" (2002), "Practical HTML: A Self-Paced Tutorial" (1996), and "Crossing the Internet Threshold: An Instructional Handbook" (1993). Roy wrote a monthly column on digital libraries for Library Journal for a decade and has written numerous articles in other professional journals. In 2003, he received the American Library Association's LITA/Library Hi Tech Award for Excellence in Communication for Continuing Education. Follow him on Twitter @rtennant.

Comments

  1. Brad Czerniak says:
    May 25, 2011 at 12:01 pm

    JSON is great for client-side implementations because JavaScript handles it so easily.

    It’s also great in other languages on the server side. PHP has json_decode(), which makes it way easier to work with (small amounts of) data encoded in JSON than the various XML parsing methods. Most every other language has baked-in JSON support by now as well.

    So JavaScript skills are not essential, and it’s definitely not all UI (front end) development.

    “XML skills” is sort of nebulous. “JSON skills” would just mean, in context, that a developer can parse JSON in their language of choice to use it in their program. The same is true for XML. Knowing basic XML syntax and the implementation-specific schema can help with debugging, but is not strictly necessary.

    That’s what bugs me about all the MARC talk — like XML vs. JSON, it’s much ado about [what should be just] data interchange formats.

  2. alex says:
    June 22, 2011 at 9:28 am

    Now that JSON is starting to take the lead it will be interesting to see whether others will start to replace their XML driven architecture with JSON.
    http://www.liquid-technologies.com/xml-editor.aspx